WO2025047372A1 - Lighting device - Google Patents

Abstract

This lighting device has: a liquid crystal light control element in which a plurality of liquid crystal panels are laminated; and a housing which has housed therein a light source, has a light emission port, and has an external appearance with which it is possible to identify a reference direction. Each of the plurality of liquid crystal panels has: a first substrate; a second substrate which is opposite to the first substrate; a liquid crystal layer which is between the first substrate and the second substrate; a first strip electrode extending in a first direction and a second strip electrode disposed parallel to the first strip electrode, both electrodes being provided on the first substrate; and a third strip electrode extending in a second direction intersecting with the first direction and a fourth strip electrode adjacent to the third strip electrode, both electrodes being provided on the second substrate. When the liquid crystal light control element is disposed overlapping the light emission port and is arranged such that the reference direction provided to the housing is oriented along the wall surface, at least one liquid crystal panel among the plurality of liquid crystal panels is set such that the normal direction of the wall surface intersects with the direction in which the first strip electrode and the second strip electrode extend, and with the direction in which the third and fourth strip electrodes extend.

Description

Lighting equipment

One embodiment of the present invention relates to a lighting device that uses the electro-optical effect of liquid crystals to control the light distribution direction of light emitted from a light source.

Technology has been developed to control the spread of illumination light by utilizing the property of liquid crystals, where the refractive index changes depending on the applied voltage (see, for example, Patent Documents 1 and 2).

International Publication No. 2022/176684 International Publication No. 2022/202299

The liquid crystal light control device disclosed as prior art is capable of distributing light emitted from a light source in a linear or cross shape on the irradiation surface, so there is a demand for the development of products with higher added value. In light of this demand, one embodiment of the present invention aims to provide a lighting device that can control light distribution using the electro-optical effect of liquid crystals, and that can create an indoor atmosphere with indirect light.

The lighting device according to one embodiment of the present invention has a liquid crystal light control element in which multiple liquid crystal panels are stacked, and a housing that houses a light source, has a light exit port, and has an appearance that allows a reference direction to be identified. Each of the multiple liquid crystal panels has a first substrate, a second substrate facing the first substrate, a liquid crystal layer between the first substrate and the second substrate, a first strip electrode provided on the first substrate and extending in a first direction, a second strip electrode arranged parallel to the first strip electrode, a third strip electrode provided on the second substrate and extending in a second direction intersecting the first direction, and a fourth strip electrode adjacent to the third strip electrode. When the liquid crystal light control element is arranged over the light exit port and the reference direction provided on the housing is arranged facing the wall surface, at least one of the multiple liquid crystal panels has a direction in which the first strip electrode and the second strip electrode extend and a direction in which the third and fourth strip electrodes extend intersect with the normal direction of the wall surface.

1 shows an overview of a lighting device according to an embodiment of the present invention. 1 is a perspective view of a liquid crystal panel constituting a liquid crystal light control element used in an illumination device according to one embodiment of the present invention; 1 is a plan view showing electrodes of a liquid crystal panel constituting a liquid crystal light control element used in a lighting device according to one embodiment of the present invention; 1 is a plan view showing electrodes of a liquid crystal panel constituting a liquid crystal light control element used in a lighting device according to one embodiment of the present invention; 4 shows the alignment state of liquid crystal molecules when a voltage is applied to a liquid crystal panel constituting a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 4 shows the alignment state of liquid crystal molecules when a voltage is applied to a liquid crystal panel constituting a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 4 shows the operation of a liquid crystal light control element used in a lighting device according to one embodiment of the present invention. 3 shows the configuration and diffusion state of a liquid crystal light control element used in a lighting device according to one embodiment of the present invention. 1 is a top view of a housing constituting an illumination device according to an embodiment of the present invention; 1 is a top view of a housing constituting an illumination device according to an embodiment of the present invention; 1 is a top view of a housing constituting an illumination device according to an embodiment of the present invention; 1 is a top view of a housing constituting an illumination device according to an embodiment of the present invention; 1 is a top view of a housing constituting an illumination device according to an embodiment of the present invention; 2 shows the configuration of a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 13 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 2 shows the configuration of a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 15 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 14. 15 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 14. 2 shows the configuration of a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 17 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 16. 2 shows the configuration of a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 19 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 18. 2 shows the configuration of a liquid crystal light control element used in an illumination device according to one embodiment of the present invention. 21 shows a light distribution pattern of a lighting device obtained by the liquid crystal light control element shown in FIG. 20.

Below, the embodiments of the present invention will be described with reference to the drawings. However, the present invention can be implemented in many different ways, and should not be interpreted as being limited to the description of the embodiments exemplified below. In order to make the explanation clearer, the drawings may show the width, thickness, shape, etc. of each part in a schematic manner compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and each figure, elements similar to those described above with respect to the previous figures may be given the same reference numerals (or reference numerals with A, B, etc. suffixed to the numerals) and detailed explanations may be omitted as appropriate. Furthermore, the letters "first" and "second" attached to each element are convenient labels used to distinguish each element, and have no further meaning unless otherwise specified.

In this specification, when a component or region is said to be "on (or under)" another component or region, unless otherwise specified, this includes not only the case where it is directly above (or directly below) the other component or region, but also the case where it is above (or below) the other component or region, i.e., the case where another component is included between the other component or region and above (or below) the other component or region.

In this specification, "light distribution" refers in the usual sense to the degree to which light emitted from a light source spreads, i.e., the distribution of luminous intensity (light strength) in each direction, and controlling the light distribution refers to intentionally controlling the degree to which light emitted from a light source spreads.

In this specification, "optical rotation" refers to the phenomenon in which the polarization axis of linearly polarized light components rotates as they pass through a liquid crystal layer.

In this specification, the "alignment direction" of an alignment film refers to the direction in which liquid crystal molecules are aligned when the alignment film is subjected to a treatment (e.g., a rubbing treatment) that imparts an alignment control force to the alignment film and the liquid crystal molecules are aligned on the alignment film. When the treatment performed on the alignment film is a rubbing treatment, the alignment direction of the alignment film is usually the rubbing direction.

In this specification, the "extension direction" of a strip electrode refers to the direction in which the long side of a pattern having a short side (width) and a long side (length) extends when the strip electrode is viewed in a plan view.

1. Overview of the Illumination Device Fig. 1 shows an overview of an illumination device 200 according to an embodiment of the present invention. The illumination device 200 includes a light source 204, a liquid crystal light control element 100 that distributes light emitted from the light source 204, and a housing 202 that houses these components. The housing 202 has a light exit 2023, and the light emitted from the light source 204 is emitted from the light exit 2023. The illumination device 200 includes a control circuit 206 that drives the liquid crystal light control element 100. The control circuit 206 may be disposed inside the housing 202 or may be disposed outside the housing 202.

When the lighting device 200 is used mainly for indirect lighting, the light exit 2023 is provided in the upper part of the housing 202 so that the light from the light source 204 is emitted upward. For example, the light exit 2023 is provided on the top surface of the housing 202. The opening shape of the light exit 2023 is arbitrary, but it is preferable that the light exit 2023 has a shape that exposes the liquid crystal light control element 100 and does not leak light emitted from the light source 204 from other areas. The light exit 2023 may be formed by a through hole that exposes the liquid crystal light control element 100. A transparent or colored cover material may be attached to the light exit 2023 so as to cover the liquid crystal light control element 100.

The liquid crystal light control element 100 is composed of one or more liquid crystal panels 102. FIG. 1 shows an embodiment in which the liquid crystal light control element 100 is composed of a first liquid crystal panel 1021, a second liquid crystal panel 1022, a third liquid crystal panel 1023, and a fourth liquid crystal panel 1024. The first liquid crystal panel 1021, the second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024 are arranged so that the flat surfaces of each panel overlap vertically.

The light source 204 emits light in the visible light band. There is no limitation on the type of light source 204, and an LED light source, a fluorescent light source, an incandescent light source, a mercury lamp, a halogen lamp, etc. can be used. The liquid crystal light control element 100 is an element that controls the distribution of light by utilizing the electro-optical effect of liquid crystal, and its mechanism is described in detail in this specification. As shown in FIG. 1, the liquid crystal light control element 100 is arranged so as to overlap with the light exit port 2023, and the light source 204 is arranged behind it (below). The lighting device 200 has a configuration in which the distribution state of light emitted from the light source 204 is controlled by the liquid crystal light control element 100, and is emitted to the external space from the light exit port 2023.

The lighting device 200 is installed, for example, indoors. The lighting device 200 can be used to irradiate light upward to illuminate a wall surface 301 and a ceiling 302. In other words, the lighting device 200 can be used for indirect lighting. As shown in FIG. 1, the lighting device 200 can be installed in contact with a wall 301 or close to the wall 301. The lighting device 200 can dynamically change the light distribution pattern while irradiating the wall surface 301 and the ceiling 302 with light distributed in a predetermined pattern by the liquid crystal light control element 100. The lighting device 200 can create lighting that looks like flickering light by the liquid crystal light control element 100, and can create an atmosphere in the room. Although details will be described later, the lighting device 200 can provide illumination by distributing light emitted from the light source 204 in a specific direction by the liquid crystal light control element 100. For example, the light emitted in all directions from the light source 204 can be distributed in a line by the liquid crystal light control element 100, and the light distribution direction (the direction in which the line-shaped light distribution extends) can be switched appropriately. The following describes in detail each element that constitutes such a lighting device 200.

2. Liquid crystal panel FIG. 2 shows a perspective view of the first liquid crystal panel 1021 constituting the liquid crystal light control element 100. The first liquid crystal panel 1021 includes a first substrate S11, a second substrate S12, a first electrode E11, a second electrode E12, a first alignment film AL11, a second alignment film AL12, and a first liquid crystal layer LC1. The first electrode E11 is provided on the first substrate S11, and the second electrode E12 is provided on the second substrate S12. The first alignment film AL11 is provided on the first substrate S11 so as to cover the first electrode E11, and the second alignment film AL12 is provided on the second substrate S12 so as to cover the second electrode E12. The first liquid crystal layer LC1 is provided between the first substrate S11 and the second substrate S12.

The first electrode E11 includes a first strip electrode E11A and a second strip electrode E11B having a strip pattern. The second electrode E12 includes a third strip electrode E12A and a fourth strip electrode E12B having a strip pattern. The first strip electrode E11A and the second strip electrode E11B are alternately arranged on the insulating surface of the first substrate S11, and the third strip electrode E12A and the fourth strip electrode E12B are alternately arranged on the insulating surface of the second substrate S12.

For the sake of explanation, Figure 2 shows the X, Y, and Z axis directions. In the following explanation, expressions such as X-axis direction, Y-axis direction, and Z-axis direction are used to specify the directions, but these expressions can also be replaced with expressions such as the X-axis direction being the first direction, the Y-axis direction being the second direction, and the Z-axis direction being the third direction or the up-down direction.

In FIG. 2, the first strip electrode E11A and the multiple second strip electrodes E11B extend in the X-axis direction, and the third strip electrode E12A and the multiple fourth strip electrodes E12B extend in the Y-axis direction. The direction in which the third strip electrode E12A and the fourth strip electrode E12B extend intersects with the direction in which the first strip electrode E11A and the second strip electrode E11B extend at an angle of, for example, 90±10 degrees, and is preferably perpendicular (90 degrees).

The extension direction of the strip electrodes constituting the first electrode E11 and the second electrode E12 may be inclined within a range of about ±10 degrees with respect to the X-axis direction and the Y-axis direction. It is also possible to adopt a configuration in which the strip electrodes extend in a predetermined direction while being partially bent. In this case, the strip electrodes will have multiple extension directions in their length direction, and each extension direction may be inclined by about ±10 degrees with respect to the X-axis direction and the Y-axis direction. Similarly, it is also possible to adopt a configuration in which the strip electrodes extend in a predetermined direction while being partially curved. In this case, the direction of the tangent at each position of the strip electrodes is regarded as the extension direction, and each extension direction may be inclined within a range of about ±10 degrees with respect to the X-axis direction and the Y-axis direction.

Furthermore, as in the embodiment described below, the extension direction of the strip electrodes constituting the first electrode E11 and the second electrode E12 may be tilted in the range of 30±10 degrees to 60±10 degrees with respect to the X-axis direction and the Y-axis direction.

The alignment direction ALD1 of the first alignment film AL11 is oriented in a direction (Y-axis direction) that intersects with the extension direction of the first strip electrode E11A and the second strip electrode E11B, and the alignment direction ALD2 of the second alignment film AL12 is oriented in a direction (X-axis direction) that intersects with the extension direction of the third strip electrode E12A and the fourth strip electrode E12B. The angle at which the extension direction of the first strip electrode E11A and the second strip electrode E11B intersects with the alignment direction ALD1, and the angle at which the extension direction of the third strip electrode E12A and the fourth strip electrode E12B intersects with the alignment direction ALD2 can be set within a range of 90±10 degrees.

The distance D between the first substrate S11 and the second substrate S12 (hereinafter sometimes referred to as the "cell gap") can be set appropriately in the range of 10 μm to 100 μm, preferably in the range of 15 μm to 55 μm. The film thicknesses of the first electrode E11 and the second electrode E12, and the first alignment film AL11 and the second alignment film AL12 are negligibly small compared to the distance between the first substrate S11 and the second substrate S12. Therefore, the distance between the first substrate S11 and the second substrate S12 can be regarded as the thickness of the first liquid crystal layer LC1. Although not shown in FIG. 2, a spacer may be provided between the first substrate S11 and the second substrate S12.

The first liquid crystal layer LC1 is made of, for example, twisted nematic liquid crystal (TN (Twisted Nematic) liquid crystal). When no voltage is applied to the first electrode E11 and the second electrode E12, the first liquid crystal layer LC1 is influenced by the alignment regulating forces of the first alignment film AL11 and the second alignment film AL12, and the long axis direction of the liquid crystal molecules LCM is aligned parallel to the alignment directions ALD1, ALD2 of the alignment films. Since the alignment direction ALD1 of the first alignment film AL11 and the alignment direction ALD2 of the second alignment film AL12 intersect (are perpendicular), the long axis direction of the liquid crystal molecules LCM gradually changes so as to be twisted 90 degrees from the first substrate S11 to the second substrate S12.

FIG. 3A shows a plan view of the first substrate S11, and FIG. 3B shows a plan view of the second substrate S12. As shown in FIG. 3A, the first electrode E11 has a structure in which a plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B are alternately arranged at a predetermined interval. Also, as shown in FIG. 3B, the second electrode E12 has a structure in which a plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B are alternately arranged at a predetermined interval.

3A, the first strip electrodes E11A are each connected to the first power supply line PE11, and the second strip electrodes E11B are each connected to the second power supply line PE12. The first power supply line PE11 is connected to the first connection terminal T11, and the second power supply line PE12 is connected to the second connection terminal T12. The first connection terminal T11 and the second connection terminal T12 are provided at the end of the first substrate S11. The first substrate S11 is provided with a third connection terminal T13 adjacent to the first connection terminal T11, and a fourth connection terminal T14 adjacent to the second connection terminal T12. The third connection terminal T13 is connected to a fifth power supply line PE15. The fifth power supply line PE15 is connected to a first power supply terminal PT11 provided on the first substrate S11. The fourth connection terminal T14 is connected to the sixth power supply line PE16. The sixth power supply line PE16 is connected to the second power supply terminal PT12 provided on the first substrate S11.

The same voltage is applied to the multiple first strip electrodes E11A via the first power supply line PE11. The same voltage is applied to the multiple second strip electrodes E11B via the second power supply line PE12. When different voltages are applied to the first connection terminal T11 and the second connection terminal T12, a potential difference occurs between the multiple first strip electrodes E11A and the multiple second strip electrodes E11B, generating an electric field. As a result, an electric field is generated in the horizontal direction (Y-axis direction) by the multiple first strip electrodes E11A and the multiple second strip electrodes E11B.

As shown in FIG. 3B, the third strip electrodes E12A are each connected to a third power supply line PE13, and the fourth strip electrodes E12B are each connected to a fourth power supply line PE14. The third power supply line PE13 is connected to a third connection terminal T13, and the fourth power supply line PE14 is connected to a fourth connection terminal T14. The third power supply terminal PT13 is provided at a position corresponding to the first power supply terminal PT11 of the first substrate S11, and the fourth power supply terminal PT14 is provided at a position corresponding to the second power supply terminal PT12 of the first substrate S11. The third power supply terminal PT13 and the first power supply terminal PT11, and the fourth power supply terminal PT14 and the second power supply terminal PT12 are electrically connected. A conductive paste is used for the electrical connection between these power supply terminals. For example, a silver paste is used as the conductive paste.

When different voltages are applied to the third connection terminal T13 and the fourth connection terminal T14, a potential difference occurs between the multiple third strip electrodes E12A and the multiple fourth strip electrodes E12B, generating an electric field. As a result, an electric field is generated in the horizontal direction (X-axis direction) by the multiple third strip electrodes E12A and the multiple fourth strip electrodes E12B.

The first substrate S11 and the second substrate S12 are translucent substrates, for example, glass substrates or resin substrates. The first electrode E11 and the second electrode E12 are transparent electrodes formed of indium tin oxide (ITO) or indium zinc oxide (IZO). The power supply lines (first power supply line PE11, second power supply line PE12, third power supply line PE13, fourth power supply line PE14) and the connection terminals (first connection terminal T11, second connection terminal T12, third connection terminal T13, fourth connection terminal T14) are formed of metal materials such as aluminum, titanium, molybdenum, and tungsten. The power supply lines (first power supply line PE11, second power supply line PE12, third power supply line PE13, fourth power supply line PE14) may be formed of the same transparent conductive film as the first electrode E11 and the second electrode E12. Of course, it is also possible to use a configuration in which either or both of the first electrode E11 and the second electrode E12 are made of a metal material or a transparent conductive film with a metal material laminated thereon.

FIG. 4A shows a partial cross-sectional view of the first liquid crystal panel 1021 when viewed from a direction perpendicular to the direction in which the first strip electrode E11A and the second strip electrode E11B extend, and FIG. 4B shows a partial cross-sectional view of the first liquid crystal panel 1021 when viewed from a direction perpendicular to the direction in which the third strip electrode E12A and the fourth strip electrode E12B extend. In FIGS. 4A and 4B, symbols are used to indicate that the alignment direction ALD1 of the first alignment film AL11 and the alignment direction ALD2 of the second alignment film AL12 are different.

As shown in Figures 4A and 4B, the first strip electrode E11A and the second strip electrode E11B are arranged with a center-to-center distance MW, and the third strip electrode E12A and the fourth strip electrode E12B are arranged with a center-to-center distance MW. The distance D between the first substrate S11 and the second substrate S12, which corresponds to the thickness of the first liquid crystal layer LC1, is equal to or greater than the center-to-center distance MW of the strip electrodes (D ≥ MW). For example, it is preferable that the distance D is at least twice as large as the center-to-center distance MW of the strip electrodes. For example, when the center-to-center distance MW is 16 μm, it is preferable that the distance D is at least 16 μm, for example, 20 μm is preferable, and 30 μm is more preferable.

The refractive index of liquid crystal changes depending on the orientation state. When no electric field is applied to the first liquid crystal layer LC1, as shown in FIG. 2, the long axis direction of the liquid crystal molecules LCM is aligned horizontally to the surface of the substrate, and is twisted 90 degrees from the first substrate S11 side to the second substrate S12 side. At this time, the first liquid crystal layer LC1 has a uniform refractive index distribution. When light is incident on the first liquid crystal panel 1021, the polarized components of the incident light are rotated by the twisting of the liquid crystal molecules LCM. At this time, the incident light transmits through the first liquid crystal layer LC1 while being rotated without being refracted (or scattered).

On the other hand, as shown in FIG. 4A, when an electric field is generated between the first strip electrode E11A and the second strip electrode E11B, the long axis of the liquid crystal molecules LCM is oriented along the electric field (when the liquid crystal has positive dielectric anisotropy). As a result, as shown in FIG. 4A, there are formed regions where the liquid crystal molecules LCM stand up above the first strip electrode E11A and the second strip electrode E11B, regions where they are oriented diagonally along the distribution of the electric field between the first strip electrode E11A and the second strip electrode E11B, and regions away from the first substrate S11 where the initial orientation state is maintained.

Similarly, as shown in FIG. 4B, when an electric field is generated between the third strip electrode E12A and the fourth strip electrode E12B, a region is formed in which the liquid crystal molecules LCM stand up above the third strip electrode E12A and the fourth strip electrode E12B, a region is formed in which the liquid crystal molecules LCM are oriented obliquely in accordance with the distribution of the electric field between the third strip electrode E12A and the fourth strip electrode E12B, and a region away from the second substrate S12 in which the initial orientation state is maintained.

Hereinafter, the electric field generated by the first strip electrode E11A and the second strip electrode E11B, and the third strip electrode E12A and the fourth strip electrode E12B will also be referred to as the "transverse electric field."

As shown in Figures 4A and 4B, when an electric field is generated between the first strip electrode E11A and the second strip electrode E11B, and between the third strip electrode E12A and the fourth strip electrode E12B, a region is formed in which the long axes of the liquid crystal molecules LCM are oriented in a convex arc shape along the direction in which the electric field is generated. That is, as shown in Figure 4A, when the initial orientation direction of the liquid crystal molecules LCM is the same as the direction of the transverse electric field, the liquid crystal molecules LCM are oriented inclined (tilted) in the normal direction to the surface of the first substrate S11 according to the intensity distribution of the electric field.

As shown in Figure 4A, the distance D is sufficiently large that the effect of the electric field on the first substrate S11 side on the orientation of the liquid crystal molecules on the second substrate S12 side is extremely small, and the orientation state of the liquid crystal molecules LCM on the second substrate S12 side is hardly affected by the electric field generated on the first substrate S11 side. The same is true for Figure 4B, where the orientation state of the liquid crystal molecules LCM on the second substrate S12 side changes due to the influence of the electric field generated by the third strip electrode E12A and the fourth strip electrode E12B, but the liquid crystal molecules LCM on the first substrate S11 side is hardly affected by this electric field.

A transverse electric field is formed by the strip electrodes, forming a convex arc-shaped dielectric constant distribution in the first liquid crystal layer LC1. Of the light incident on the first liquid crystal layer LC1, the polarized components parallel to the direction of the initial alignment of the liquid crystal molecules LCM are diffused radially by the dielectric constant distribution. As shown in Figures 4A and 4B, the direction of the initial alignment of the liquid crystal molecules LCM intersects (is perpendicular) on the first substrate S11 side and the second substrate S12 side, making it possible to diffuse light in different directions on the first substrate S11 side and the second substrate S12 side.

Figure 5 shows the first liquid crystal panel 1021, with the first strip electrode E11A and second strip electrode E11B of the first electrode E11 extending in the X-axis direction, and the third strip electrode E12A and fourth strip electrode E12B of the second electrode E12 extending in the Y-axis direction. The alignment direction ALD1 of the first alignment film AL1 is parallel to the Y-axis direction, and the alignment direction ALD2 of the second alignment film AL2 is parallel to the X-axis direction. Therefore, the long axes of the liquid crystal molecules LCM on the first substrate S11 side are oriented in the Y-axis direction, and the long axes of the liquid crystal molecules LCM on the second substrate S12 side are oriented in the X-axis direction. FIG. 5 also shows a state in which the control circuit 206 applies a high-level voltage VH to the first strip electrode E11A, a low-level voltage VL (VH>VL) to the second strip electrode E11B, a high-level voltage VH to the third strip electrode E12A, and a low-level voltage VL (VH>VL) to the fourth strip electrode E12B.

Light emitted from the light source is incident on the first liquid crystal panel 1021 from the first substrate S11 side. This light has a first polarization component PL1 and a second polarization component PL2. Here, the first polarization component PL1 corresponds to P waves (having amplitude in the X-axis direction), and the second polarization component PL2 corresponds to S waves (having amplitude in the Y-axis direction). As shown in the table inserted in Figure 5, the light incident on the first liquid crystal panel 1021 is subjected to optical effects such as transmission, optical rotation, and diffusion by the first liquid crystal layer LC1.

Here, "transmission" in the table refers to the transmission of a specific polarized component without change in its polarization axis or in its light distribution state. As mentioned above, "optical rotation" refers to the phenomenon in which the polarization axis of a linearly polarized component rotates as it passes through the liquid crystal layer. "Diffusion (X)" indicates that the polarized component is diffused in the X-axis direction, and "Diffusion (Y)" indicates that the polarized component is diffused in the Y-axis direction. The notations shown in the table in FIG. 5 are the same in each of the embodiments described below.

Of the light incident from the first substrate S11 side, the first polarization component PL1 is a P wave. The direction of the polarization axis of the first polarization component PL1 intersects with the long axis direction of the liquid crystal molecules LCM on the first electrode E11 side. Therefore, the first polarization component PL1 is transmitted as it is without being affected by the refractive index distribution formed by the liquid crystal molecules LCM. As the first polarization component PL1 travels through the first liquid crystal layer LC1 from the first substrate S11 side to the second substrate S12 side, it is rotated by 90 degrees and transitions to an S wave state. Since the first polarization component PL1 becomes an S wave on the second electrode E12 side, its polarization direction intersects with the long axis direction of the liquid crystal molecules LCM. This first polarization component PL1 is transmitted as it is without being affected by the refractive index distribution formed by the liquid crystal molecules LCM. On the other hand, the second polarization component PL2 is an S wave. The direction of the polarization axis of the second polarized component PL2 is parallel to the long axis direction of the liquid crystal molecules LCM on the first electrode E11 side, and is affected by the refractive index distribution formed by the liquid crystal molecules LCM and diffuses in the Y axis direction. The second polarized component PL2 is rotated 90 degrees and transitions to a P wave state as it travels through the first liquid crystal layer LC1 from the first substrate S11 side to the second substrate S12 side. The polarization direction of this second polarized component PL2 is parallel to the long axis direction of the liquid crystal molecules LCM on the second electrode E12 side. Therefore, this second polarized component PL2 is affected by the refractive index distribution formed by the liquid crystal molecules LCM and diffuses in the X axis direction.

In this way, when light is incident on the first liquid crystal panel 1021 shown in FIG. 5, the first polarized component PL1 (P wave) is not diffused, but is rotated by the first liquid crystal layer LC1 and emitted in the form of an S wave. The second polarized component PL2 (S wave) is diffused once in each of the Y-axis direction and the X-axis direction, and is rotated by the first liquid crystal layer LC1 and emitted in the form of a P wave.

Figure 5 shows an example in which a voltage is applied to each of the first electrode E11 and the second electrode E12. By changing the voltage application conditions, the light emitted from the light source can be distributed in a line-shaped light distribution pattern extending in the X-axis direction and a line-shaped light distribution pattern extending in the Y-axis direction.

3. Liquid crystal light control element The liquid crystal light control element 100 is composed of a plurality of liquid crystal panels having the same configuration as the first liquid crystal panel 1021. Fig. 6 shows the liquid crystal light control element 100 composed of a plurality of liquid crystal panels. The liquid crystal light control element 100 has a structure in which the first liquid crystal panel 1021, the second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024 are arranged in a stacked manner in the Z-axis direction. For the sake of explanation, Fig. 6 shows a state in which the liquid crystal panels are arranged apart from each other, but the actual liquid crystal light control element 100 has a structure in which the liquid crystal panels are bonded together with a light-transmitting adhesive.

The second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024 have the same configuration as the first liquid crystal panel 1021 shown in FIG. 5. FIG. 6 shows a configuration in which the first liquid crystal panel 1021 has a first substrate S11, a second substrate S12, a first electrode E11, and a second electrode E12. Similar to this configuration, the second liquid crystal panel 20 has a first substrate S21, a second substrate S22, a first electrode E21, and a second electrode E22, the third liquid crystal panel 30 has a first substrate S31, a second substrate S32, a first electrode E31, and a second electrode E32, and the fourth liquid crystal panel 40 has a first substrate S41, a second substrate S42, a first electrode E41, and a second electrode E42.

The first electrodes E11, E21, E31, E41 are composed of first strip electrodes E11A, E21A, E31A, E41A and second strip electrodes E11B, E21B, E31B, E41B, and these strip electrodes extend in the X-axis direction, and the second electrodes E12, E22, E32, E42 are composed of third strip electrodes E12A, E22A, E32A, E42A and fourth strip electrodes E12B, E22B, E32B, E42B, and these strip electrodes extend in the Y-axis direction.

In the first liquid crystal panel 1021, the second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024, the first strip electrodes E11A, E21A, E31A, E41A and the second strip electrodes E11B, E21B, E31B, E41B extend in the same direction, and the third strip electrodes E12A, E22A, E32A, E42A and the fourth strip electrodes E12B, E22B, E32B, E42B extend in the same direction.

A low-level voltage VL, a high-level voltage VH, and a constant voltage CV are applied to each liquid crystal panel as control signals. The low-level voltage VL is, for example, 0V or -15V, and the high-level voltage VH is, for example, 30V (for VL=0V) or 15V (for VL=-15V). The constant voltage CV is, for example, a voltage signal that is an intermediate voltage between VL1 and VH1, or 0V (ground).

6 shows a state in which a high-level voltage VH and a low-level voltage VL are applied as control signals to the first electrode E11 of the first liquid crystal panel 1021, the first electrode E21 of the second liquid crystal panel 1022, the first electrode E31 of the third liquid crystal panel 1023, and the first electrode E41 of the fourth liquid crystal panel 1024, and a constant voltage CV is applied as a control signal to the second electrode E12 of the first liquid crystal panel 1021, the second electrode E22 of the second liquid crystal panel 1022, the second electrode E32 of the third liquid crystal panel 1023, and the second electrode E42 of the fourth liquid crystal panel 1024. That is, the liquid crystal molecules are aligned by a transverse electric field on the first substrates S11, S21, S31, and S41 sides of each liquid crystal panel, and the liquid crystal molecules are in an initial alignment state on the second substrates S12, S22, S23, and S24 sides.

FIG. 6 shows that light emitted from a light source enters the first liquid crystal panel 1021 side and exits from the fourth liquid crystal panel 1024 side. The incident light contains a first polarized component PL1 (P wave) and a second polarized component PL2 (S wave), and the table inserted in FIG. 6 shows how the diffusion, optical rotation, and transmission change at each liquid crystal panel.

For example, in the case of the first liquid crystal panel 1021, the first polarized component PL1 (P wave) of the light emitted from the light source is transmitted through the first electrode E11 side, rotates as it passes through the first liquid crystal layer LC1, transitions to an S wave, and is transmitted through the second electrode E12 side to be emitted, while the second polarized component PL2 (S wave) is diffused in the Y-axis direction on the first electrode E11 side, rotates as it passes through the first liquid crystal layer LC1, transitions to a P wave, and is transmitted through the second electrode E12 side to be emitted. In this way, the first polarized component PL1 and the second polarized component PL2 rotate in the direction of the polarization axis by passing through the first liquid crystal panel 1021, and are diffused by the influence of the electric field. Such a change is repeated each time they pass through the second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024.

As shown in the table inserted in FIG. 6, the first polarized component (P wave) of the light emitted from the light source is diffused in the Y-axis direction by the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 (twice in total) by passing through the first liquid crystal panel 1021 to the fourth liquid crystal panel 1024, rotated four times in the liquid crystal layer of each liquid crystal panel, and emitted in the form of a P wave. The second polarized component PL2 (S wave) is diffused in the Y-axis direction by the first liquid crystal panel 1021 and the third liquid crystal panel 1023 (twice in total) by passing through the first liquid crystal panel 1021 to the fourth liquid crystal panel 1024, rotated four times in the liquid crystal layer of each liquid crystal panel, and emitted in the form of an S wave. In other words, the voltage application conditions shown in FIG. 6 distribute the light emitted from the light source by spreading it in the Y-axis direction. Such a light distribution pattern spreads the light in one axis direction, so it can be called a line light distribution. In addition, as shown in FIG. 6, by driving only the electrodes on one substrate side of each liquid crystal panel, the polarized components that rotate while passing through the liquid crystal panel can be diffused in only one direction, and the weakening of the light diffusion in a specific direction caused by the diffusion before and after the rotation is suppressed. This means that by driving only the electrodes on one substrate side of each liquid crystal panel, the light diffusion direction can be limited, and only the polarized components that are parallel to the orientation direction of the alignment film that covers the electrodes can be diffused. Therefore, by making the orientations of the electrodes of each liquid crystal panel different from each other, it is possible to diffuse the polarized components of the incident light in various directions. This will be described in detail in a later embodiment.

Note that the voltage application conditions in FIG. 6 are just an example, and the voltage application conditions that can be applied to the liquid crystal light control element 100 are not limited to those shown. For example, if a constant voltage CV is applied as a control signal to the first electrode of each liquid crystal panel, and a high-level voltage VH and a low-level voltage VL are applied as control signals to the second electrode, a line light distribution pattern spreading in the X-axis direction can be formed. The number of liquid crystal panels that make up the liquid crystal light control element 100 is not limited to four, and can be increased. In addition, the way in which the liquid crystal panels are overlapped can be changed. For example, the upper liquid crystal panel can be rotated at a predetermined angle relative to the lower liquid crystal panel and overlapped.

4. Shape of the Housing As described with reference to FIG. 6, the liquid crystal light control element 100 controls the distribution of light emitted from the light source 204. The lighting device 200 can produce illumination for an indoor space by emitting light distributed by the liquid crystal light control element 100. In order to produce an effective illumination using light whose distribution is controlled by the liquid crystal light control element 100, it is necessary to arrange the lighting device 200 facing in an appropriate direction so that the walls and ceiling are illuminated by the distributed light. In other words, it is required that the user can identify in which direction the lighting device 200 should be installed.

Figure 7 shows a top view of the housing 202 used in the lighting device 200. The housing 202 has a space therein for storing the liquid crystal light control element 100 and the light source 204, and has a light exit port 2023 on the top surface. When viewed from above as shown in Figure 7, the housing 202 has a shape in which part of its circular outline has been cut out in a straight line. The side (body) of the housing 202 has a curved shape, but this cut-out part is molded into a flat surface. This flat part has a different shape from the other parts of the exterior of the housing 202, and forms a reference surface 2021 that can be identified from the exterior.

This reference surface 2021 is formed by a flat surface within the cylindrical exterior shape of the housing 202, so a psychological effect can be expected that will naturally induce the user to install the lighting device with this surface facing the wall. In this way, by making a part of the shape of the housing 202 visually distinguishable from the other parts, that part can be used as the reference surface 2021, and the direction that serves as the reference when placing the lighting device 200 (the direction in which the housing 202 faces the wall surface 301) can be displayed.

FIG. 7 shows that the reference surface 2021 on the housing 202 is installed facing the wall surface 301. The direction in which the liquid crystal light control element 100 diffuses light is determined by the direction in which the strip-shaped electrode pattern extends. Therefore, when installing the liquid crystal light control element 100 inside the housing 202, it is necessary to pay attention to the position of the reference surface 2021 and the direction in which the strip-shaped electrodes extend.

Fig. 7 shows a top view of the liquid crystal light control element 100 in the housing 202. As described with reference to Fig. 6, when the strip electrodes forming the first electrodes E11, E21, E31, and E41 extend in the X-axis direction and the second electrodes E12, E22, E32, and E42 extend in the Y-axis direction, it is preferable that the liquid crystal light control element 100 is disposed in the housing 202 so that the extension line of the tangent line T1 to the plane forming the reference surface 2021 does not intersect with the X-axis direction and the Y-axis direction at an angle smaller than 90 degrees, as shown in Fig. 7. In this case, the angle _θX at which the tangent line T1 intersects with the X-axis direction and the angle _θY at which the tangent line T1 intersects with the Y-axis direction may be equal to each other, or one may be larger than the other. For example, the angle _θX at which the tangent line T1 intersects with the X-axis direction and the angle θY at which the tangent line T1 intersects with the _Y -axis direction may both be 45 degrees, or when the angle _θX or the angle _θY becomes larger, the other angle may become smaller so that they satisfy a complementary angle relationship.

In this way, by arranging the liquid crystal light control element 100 in the housing 202 with the reference plane 2021 as a reference, the lighting device 200 can be installed so that the extension lines in both the X-axis direction and the Y-axis direction intersect obliquely with the wall surface 301, rather than perpendicularly. As a result, when the liquid crystal light control element 100 emits light that is distributed in lines in the X-axis direction and the Y-axis direction, both line distributions can be irradiated onto the wall surface 301.

The shape of the housing 202 is not limited to a circular shape in a plan view. For example, as shown in FIG. 8, it may be rectangular in a plan view. The housing 202 shown in FIG. 8 has a reference surface 2021 formed of a flat surface, similar to the example shown in FIG. 7. If the shape of the housing 202 is rectangular in a plan view, the side surface of the housing 202 is formed of a flat surface, so that the reference surface 2021 may not be distinguishable. In such a case, the shape of the housing 202 may be trapezoidal in a plan view so that the plane that becomes the reference surface 2021 can be distinguished from the outside. Since the two opposing sides of a trapezoid are formed by a short side and a long side, the surface on the short side of the trapezoid and the surface on the long side of the trapezoid can be distinguished from the outside, and the surface that becomes the reference surface 2021 can be distinguished from other surfaces. FIG. 8 shows the surface on the short side of the trapezoid as the reference surface 2021, but the surface on the long side can also be the reference surface 2021.

The portion of the housing 202 indicating the reference direction is not limited to being planar. For example, as shown in the top view of the housing 202 in FIG. 9, the sign 2022 may be formed by a shape in which a part of the housing 202 protrudes outward. In this way, even if the housing 202 does not have a flat portion, the sign 2022 can be provided in a shape that is identifiable from the outside, thereby indicating the reference direction when placing the lighting device 200. In this case, by placing the liquid crystal light control element 100 in the housing 202 in the same manner as described in FIG. 7, using the tangent line T1 that touches the sign 2022 as a reference, both the X-axis direction and the Y-axis direction can intersect with the wall surface 301.

Also, as shown in FIG. 10, the shape of the sign 2022 is not limited to a convex shape that protrudes outward from the housing 202, but may have a concave shape. By forming a part of the outer surface of the housing 202 into a concave shape, a part that is distinguishable from other parts in terms of the external shape can be formed, and a visible identification part can be formed.

Note that the convex mark 2022 shown in FIG. 9 and the concave mark 2022 shown in FIG. 10 may be formed over the entire vertical direction of the side surface of the housing 202, or may be formed only in a portion of the side surface. For example, the convex or concave mark 2022 may be formed on the upper side of the side surface of the housing 202 so that it is easily visible from the external shape.

Furthermore, as shown in FIG. 11, the sign 2022 may be formed by a marker attached to the housing 202, rather than by changing the shape of a portion of the housing 202. This marker may be represented by letters, figures, or symbols, and may be colored. FIG. 11 shows a case in which the housing 202 is hexagonal in plan view, but by displaying the sign 2022 with letters, figures, or symbols, it is possible to avoid affecting the external shape of the housing 202. Even when a complex design is applied to the exterior of the housing 202, it is possible to avoid affecting the design by using the sign 2022 represented by letters, figures, or symbols.

As described with reference to Figures 7 to 11, by providing a reference surface 2021 or a sign 2022 that can be identified from the outside on a part of the housing 202, the lighting device 200 can be installed facing the wall surface 301 in accordance with the direction of light distribution by the liquid crystal light control element 100.

3. Configuration and driving method of liquid crystal light control element As explained with reference to Fig. 6, the liquid crystal light control element 100 is composed of multiple liquid crystal panels. There are various variations in the number of liquid crystal panels to be stacked and the way they are stacked, which makes it possible to vary the state of light irradiated onto the irradiation surface. Some specific examples are shown below.

[First embodiment]
FIG. 12 shows the configuration of the liquid crystal light control element 100 used in the lighting device 200. FIG. 12 shows an example in which the liquid crystal light control element 100 is composed of four liquid crystal panels (a first liquid crystal panel 1021, a second liquid crystal panel 1022, a third liquid crystal panel 1023, and a fourth liquid crystal panel 1024). The first liquid crystal panel 1021, the second liquid crystal panel 1022, the third liquid crystal panel 1023, and the fourth liquid crystal panel 1024 are stacked in the Z-axis direction. FIG. 12 shows that the first liquid crystal panel 1021, the second liquid crystal panel 1022, the third liquid crystal panel, and the fourth liquid crystal panel 1024 are stacked in this order from the bottom. FIG. 12 also shows that light emitted from a light source enters the first liquid crystal panel 1021 and is emitted from the fourth liquid crystal panel 1024. In this case, the light incident on the first liquid crystal panel 1021 has a first polarized component PL1 which is a P wave having an amplitude in the X-axis direction, and a second polarized component PL2 which is an S wave having an amplitude in the Y-axis direction. The first polarized component PL1 is rotated every time it passes through a liquid crystal layer, transitioning from a P wave to an S wave, and transitioning from an S wave to a P wave when it passes through the next liquid crystal layer. The same is true for the second polarized component PL2 (S wave).

Each liquid crystal panel has first electrodes E11, E21, E31, E41 extending in the X-axis direction on the first substrate S11, S21, S31, S41, and second electrodes E12, E22, E32, E42 extending in the Y-axis direction on the second substrate S12, S22, S32, S42. The strip electrodes of the first electrodes E11, E21, E31, E41 and the strip electrodes of the second electrodes E12, E22, E32, E42 are arranged to intersect at an angle of 90±10 degrees. The alignment direction ALD1 of the alignment film on the first substrate S11, S21, S31, S41 side is oriented in the Y-axis direction, and the alignment direction ALD2 of the alignment film on the second substrate S12, S22, S32, S42 side is oriented in the X-axis direction.

As explained with reference to FIG. 6, it is possible to apply a control voltage (voltage application condition with high-level voltage VH and low-level voltage VL) that aligns the liquid crystal molecules by a transverse electric field to the first electrodes E11, E21, E31, and E41 and the second electrodes E12, E22, E32, and E42, as well as a control voltage (voltage application condition with constant voltage CV) that does not change the alignment state of the liquid crystal molecules.

Tables 1 and 2 show the voltage application conditions of the liquid crystal light control element 100 according to this embodiment. In Table 1, the column labeled "Liquid Crystal Panel" shows numbers corresponding to the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024. The column labeled "Electrode" shows the direction in which the strip electrodes of each liquid crystal panel extend, and as described with reference to FIG. 12, Table 1 shows that in each liquid crystal panel, the direction in which the strip electrodes of the first electrodes E11, E21, E31, and E41 extend and the direction in which the strip electrodes of the second electrodes E12, E22, E32, and E42 extend are arranged to intersect at an angle of 90±10 degrees. The figures in the column labeled "Liquid Crystal" show the orientation direction of the liquid crystal molecules on each substrate (the long axis direction of the liquid crystal molecules coincides with the initial orientation direction of the alignment film). The column "Drive" indicates the application state of the control voltage to the first electrodes E11, E21, E31, E41 and the second electrodes E12, E22, E32, E42. "ON" indicates that a high-level voltage VH and a low-level voltage VL are applied to control the alignment state of the liquid crystal molecules by a transverse electric field, and "OFF" indicates that a constant voltage CV is applied. The column "Alignment direction of alignment film" indicates the alignment direction of the alignment film provided on each liquid crystal panel with an arrow. Here, the arrow pointing to the horizontal direction indicates that the alignment direction of the alignment film is parallel to the X-axis direction, and the arrow pointing to the vertical direction indicates that the alignment direction of the alignment film is parallel to the Y-axis direction. The column "Diffusion direction of polarized light component" indicates the direction in which the first polarized light component or the second polarized light component is diffused. Here, "Diffusion (X)" means that the polarized component is diffused in the X-axis direction, "Diffusion (Y)" means that the polarized component is diffused in the Y-axis direction, and "Transmission" means that the polarization axis of a given polarized component does not change and the light distribution state does not change and the component is transmitted as is. The contents displayed in each column of Table 1 are the same in the following embodiments.

Table 1 shows the first voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The first voltage application condition shown in Table 1 is a condition in which the first electrodes E11, E21, E31, and E41 are turned on (ON) to align the liquid crystal molecules with a transverse electric field, and the second electrodes E12, E22, E32, and E42 are turned off (OFF). Under these conditions, the first polarized component PL1 is diffused in the Y-axis direction by the first electrode E21 of the second liquid crystal panel 1022 and the first electrode E41 of the fourth liquid crystal panel 1024, and the second polarized component PL2 is diffused in the Y-axis direction by the first electrode E11 of the first liquid crystal panel 1021 and the first electrode E31 of the third liquid crystal panel 1023. In other words, under the first voltage application condition, both the first polarized component PL1 and the second polarized component PL2 are diffused in the Y-axis direction, and a line light distribution (L1) in which light is diffused in the Y-axis direction is formed.

Table 2 shows the second voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The second voltage application condition shown in Table 2 is a condition in which the first electrodes E11, E21, E31, and E41 are turned off (OFF) and the second electrodes E12, E22, E32, and E42 are turned on (ON) to align the liquid crystal molecules with a transverse electric field. Under such conditions, the first polarized component PL1 is diffused in the X-axis direction by the second electrode E22 of the second liquid crystal panel 1022 and the second electrode E42 of the fourth liquid crystal panel 1024, and the second polarized component PL2 is diffused in the X-axis direction by the second electrode E12 of the first liquid crystal panel 1021 and the second electrode E32 of the third liquid crystal panel 1023. In other words, under the second voltage application condition, both the first polarized component PL1 and the second polarized component PL2 are diffused in the X-axis direction, and a line light distribution (L2) in which light is diffused in the X-axis direction is formed.

FIG. 13 shows the light distribution patterns formed under the first voltage application condition and the second voltage application condition. FIG. 13 shows an example in which the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024 are arranged in a rotated state within a range of 45±10 degrees relative to the wall surface 301. Under the first voltage application condition, a line light distribution L1 extending in the Y-axis direction is formed, and under the second voltage application condition, a line light distribution L2 extending in the X-axis direction is formed. Parts of these two line light distributions L1 and L2 are irradiated onto the wall, but since the directions in which the distributed light extends are different, the irradiated positions are different. The liquid crystal light control element 100 is driven by the control circuit 206 (see FIG. 1 and FIG. 5) so that the first voltage application condition and the second voltage application condition are alternately repeated. By switching between the two voltage application conditions at a low frequency that can be tracked by human vision, it is possible to create the effect of the light irradiated onto the wall surface 301 and the ceiling 302 flickering. In this case, the voltage application conditions may be switched at a constant cycle, or may be switched with 1/f fluctuation.

The lighting device 200 according to this embodiment uses a liquid crystal light control element 100 that uses four liquid crystal panels, and can form a line light distribution in which light extends in two different directions. By alternately switching between these line light distributions, it is possible to create an indoor space with indirect lighting. Furthermore, by switching the line light distribution at a predetermined or random cycle as described above, the fluctuation is visualized by the diffused light irradiated onto the wall surface. In this embodiment, the axis of the fluctuation of the diffused light (i.e. the central axis of the line light distribution) itself moves to multiple positions, which adds diversity to the expression of the fluctuation.

[Second embodiment]
The lighting device 200 according to this embodiment has a configuration in which the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 constituting the liquid crystal light control element 100 in the lighting device 200 shown in the first embodiment are rotated with respect to the first liquid crystal panel 1021 and the second liquid crystal panel 1022. In the following description, the differences from the first embodiment will be mainly described, and descriptions of common parts will be omitted as appropriate.

FIG. 14 shows the configuration of the liquid crystal light control element 100 according to this embodiment. The liquid crystal light control element 100 is composed of four liquid crystal panels (first liquid crystal panel 1021, second liquid crystal panel 1022, third liquid crystal panel 1023, and fourth liquid crystal panel 1024), which are stacked in the Z-axis direction, as in the first embodiment. However, in this embodiment, the third liquid crystal panel 1023 and fourth liquid crystal panel 1024 are rotated within a range of 45±10 degrees relative to the first liquid crystal panel 1021 and second liquid crystal panel 1022.

By overlapping the liquid crystal panels in this manner, the direction in which the stripe patterns of the first electrodes E31, E41 of the third and fourth liquid crystal panels 1023, 1024 extend is tilted within a range of 45±10 degrees relative to the first electrodes E11, E21 of the first and second liquid crystal panels 1021, 1022. Similarly, the direction in which the stripe patterns of the second electrodes E32, E42 of the third and fourth liquid crystal panels 1023, 1024 extend is also tilted within a range of 45±10 degrees relative to the second electrodes E12, E22 of the first and second liquid crystal panels 1021, 1022. The same is true for the orientation directions ALD1, ALD2 of the alignment films and the orientation direction of the liquid crystal molecules LCM.

Below are the voltage application conditions for the liquid crystal light control element 100. In this embodiment, there are four voltage application conditions because the two liquid crystal panels are rotated by 45 degrees.

Table 3 shows the first voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The first voltage application condition shown in Table 3 is a condition in which the first electrodes E11 and E21 are turned on (ON) in the first liquid crystal panel 1021 and the second liquid crystal panel 1022 to align the liquid crystal molecules with a transverse electric field, and the second electrodes E12 and E22 are turned off (OFF). In the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024, the first electrodes E31 and E41 and the second electrodes E32 and E42 are both turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the first substrates S11 and S21 of the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are diffused in the Y-axis direction. In other words, under the first voltage application condition, a linear light distribution (L1) is formed in which the incident light from the light source is diffused in the Y-axis direction.

Table 4 shows the second voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The second voltage application condition shown in Table 4 is a condition in which the first electrodes E31 and E41 are turned on (ON) in the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a horizontal electric field, and the second electrodes E32 and E32 are turned off (OFF). For the first liquid crystal panel 1021 and the second liquid crystal panel 1022, the first electrodes E11 and E21 and the second electrodes E12 and E22 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the first substrates S31 and S41 of the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are diffused in a direction tilted at 45±10 degrees with respect to the Y-axis direction. In other words, under the second voltage application condition, a line light distribution (L2) is formed in which the incident light from the light source is diffused in a direction tilted at 45 degrees with respect to the Y-axis direction. Here, "Diffusion (Y-45°)" in Table 4 indicates that the light is diffused in a direction tilted 45 degrees clockwise with respect to the Y-axis direction. This notation in the table is the same in the following embodiments. Thus, in this embodiment, the polarization components acting on the first liquid crystal panel 1021 and the second liquid crystal panel 1022, and the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 differ by 45 degrees. Note that the direction in which the line light distribution (L2) extends will be in the range of 45±10 degrees with respect to the Y-axis direction, depending on the rotation angle of the liquid crystal panels.

Table 5 shows the third voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The third voltage application condition shown in Table 5 is a condition in which the first electrodes E11 and E21 are turned off (OFF) and the second electrodes E12 and E22 are turned on (ON) in the first liquid crystal panel 1021 and the second liquid crystal panel 1022 to align the liquid crystal molecules with a transverse electric field. In the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024, the first electrodes E31 and E41 and the second electrodes E32 and E42 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the alignment direction of the alignment film of the second substrates S12 and S22 of the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are diffused in the X-axis direction. In other words, under the third voltage application condition, a linear light distribution (L3) is formed in which the incident light from the light source is diffused in the X-axis direction.

Table 6 shows the fourth voltage application condition and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The fourth voltage application condition shown in Table 6 is a condition in which the first electrodes E31 and E41 are turned off (OFF) and the second electrodes E32 and E42 are turned on (ON) in the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a transverse electric field. For the first liquid crystal panel 1021 and the second liquid crystal panel 1022, the first electrodes E11 and E21 and the second electrodes E12 and E22 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the second substrates S32 and S42 of the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are diffused in a direction tilted at 45 degrees with respect to the X-axis direction. In other words, under the second voltage application condition, a line light distribution (L4) is formed in which the incident light from the light source is diffused in a direction tilted at 45 degrees with respect to the X-axis direction. The direction in which the line light distribution (L4) extends will be within a range of 45±10 degrees with respect to the X-axis direction, depending on the rotation angle of the liquid crystal panel.

FIG. 15A shows the light distribution patterns formed under the first to fourth voltage application conditions. That is, it shows the light distribution patterns formed by the line light distributions L1 to L4. Note that FIG. 15A shows a state in which the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are arranged in a rotated state within a range of 45±10 degrees with respect to the wall surface 301. Under the first voltage application condition, a line light distribution L1 extending in the Y-axis direction is formed, under the second voltage application condition, a line light distribution L2 extending in a direction inclined at 45 degrees with respect to the Y-axis direction is formed, under the third voltage application condition, a line light distribution L3 extending in the X-axis direction is formed, and under the fourth voltage application condition, a line light distribution L4 extending in a direction inclined at 45 degrees with respect to the X-axis direction is formed. Of these four line light distributions L1, L2, L3, and L4, at least three line light distributions L1, L2, and L3 are irradiated onto the wall surface 301, but the irradiated positions are different because the directions in which the distributed light extends are different. In this way, by rotating the third and fourth liquid crystal panels 1023 and 1024 of the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024 by 45±10 degrees, the number of line light distributions irradiated onto the wall surface 301 can be increased. In other words, as the fluctuation is visualized by the diffused light irradiated onto the wall surface 301, the axis of the fluctuation expressed by the central axis of the line light distribution moves to multiple positions, and the above-mentioned fluctuation expression can be made more diverse. Note that the first to fourth voltage application conditions are driven for each liquid crystal panel as in the first embodiment, but the order of the voltage application conditions is arbitrary and is not limited to the ascending order from first to fourth.

FIG. 15B shows the state where each liquid crystal panel (first liquid crystal panel 1021, second liquid crystal panel 1022, third liquid crystal panel 1023, fourth liquid crystal panel 1024) is further rotated within a range of 22.5±10 degrees with respect to the arrangement of liquid crystal panels shown in FIG. 15A. With such an arrangement of liquid crystal panels, it becomes possible to project all four line light distributions L1, L2, L3, and L4 onto the wall surface 301. In addition, the projection range of the line light distributions L1, L2, L3, and L4 emitted from the liquid crystal light control element 100 can be expanded.

The lighting device 200 according to this embodiment can increase the number of linear light distributions irradiated onto the wall surface 301 and ceiling 302 by rotating two of the four liquid crystal panels that make up the liquid crystal light control element 100 within a range of 45±10 degrees. This configuration can provide more indirect lighting to enhance the effect of the room space.

In this embodiment, the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are described as being rotated within a range of 45±10 degrees relative to the first liquid crystal panel 1021 and the second liquid crystal panel 1022, but these relationships are relative, and it can also be interpreted as the first liquid crystal panel 1021 and the second liquid crystal panel 1022 being rotated within a range of 45±10 degrees relative to the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024.

[Third embodiment]
This embodiment shows an example of a light distribution pattern of an illumination device using a liquid crystal light control element 100 that uses six liquid crystal panels.

FIG. 16 shows a configuration in which the liquid crystal light control element 100 according to this embodiment is composed of six liquid crystal panels (first liquid crystal panel 1021, second liquid crystal panel 1022, third liquid crystal panel 1023, fourth liquid crystal panel 1024, fifth liquid crystal panel 1025, and sixth liquid crystal panel 1026) that are stacked in the Z-axis direction. In this embodiment, the third liquid crystal panel 1023 and fourth liquid crystal panel 1024 are rotated within a range of 30±10 degrees relative to the first liquid crystal panel 1021 and second liquid crystal panel 1022, and the fifth liquid crystal panel 1025 and sixth liquid crystal panel 1026 are rotated within a range of 60±10 degrees.

As a result of this overlapping, the direction in which the band-shaped patterns of the first electrodes E31, E41 of the third and fourth liquid crystal panels 1023, 1024 extend is tilted within a range of 30±10 degrees relative to the first electrodes E11, E21 of the first and second liquid crystal panels 1021, 1022, and the direction in which the band-shaped patterns of the first electrodes E51, E61 of the fifth and sixth liquid crystal panels 1025, 1026 extend is tilted within a range of 60±10 degrees. Similarly, the direction in which the stripe patterns of the second electrodes E32, E42 of the third and fourth liquid crystal panels 1023, 1024 extend is inclined within a range of 30±10 degrees relative to the second electrodes E12, E22 of the first and second liquid crystal panels 1021, 1022, and the direction in which the stripe patterns of the second electrodes E52, E52 of the fifth and sixth liquid crystal panels 1025, 1026 extend is inclined within a range of 60±10 degrees. The same is true for the orientation directions ALD1, ALD2 of the alignment films and the orientation direction of the liquid crystal molecules LCM.

Below are the conditions for applying voltage to the liquid crystal light control element 100. In this embodiment, two liquid crystal panels are rotated within a range of 30±10 degrees, and two liquid crystal panels are rotated within a range of 60±10 degrees, so there are six voltage application conditions.

Table 7 shows the first voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The first voltage application condition shown in Table 7 is a condition in which the first electrodes E11 and E21 are turned on (ON) in the first liquid crystal panel 1021 and the second liquid crystal panel 1022 to align the liquid crystal molecules with a horizontal electric field, and the second electrodes E12 and E22 are turned off (OFF). In the third to fifth liquid crystal panels 1023, 1024, 1025, and 1026, the first electrodes E31, E41, E51, and E61 and the second electrodes E32, E42, E52, and E62 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the first substrates S11 and S21 of the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are diffused in the Y-axis direction. In other words, under the first voltage application condition, a linear light distribution (L1) is formed in which the incident light from the light source is diffused in the Y-axis direction.

Table 8 shows the second voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The second voltage application conditions shown in Table 8 are conditions in which the first electrodes E31 and E41 are turned on (ON) in the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a transverse electric field, and the second electrodes E32 and E42 are turned off (OFF). For the first liquid crystal panel 1021, the second liquid crystal panel 1022, the fifth liquid crystal panel 1025, and the sixth liquid crystal panel 1026, the first electrodes E11, E21, E51, and E61 and the second electrodes E12, E22, E52, and E62 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment films of the first substrates S31 and S41 of the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are diffused in a direction tilted within a range of 30±10 degrees with respect to the Y-axis direction. That is, under the second voltage application condition, a line light distribution (L2) is formed in which the incident light from the light source is diffused once in a direction tilted within a range of 30±10 degrees with respect to the Y-axis direction.

Table 9 shows the third voltage application conditions and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The third voltage application condition shown in Table 9 is a condition in which the first electrodes E51 and E61 are turned on (ON) in the fifth liquid crystal panel 1025 and the sixth liquid crystal panel 1026 to align the liquid crystal molecules with a transverse electric field, and the second electrodes E52 and E62 are turned off (OFF). In the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024, the first electrodes E11, E21, E31, and E41 and the second electrodes E12, E22, E32, and E42 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment films of the first substrates S51 and S61 of the fifth liquid crystal panel 1025 and the sixth liquid crystal panel 1026 are diffused in a direction tilted within a range of 60±10 degrees with respect to the Y-axis direction. That is, under the third voltage application condition, a line light distribution (L3) is formed in which the incident light from the light source is diffused once in a direction tilted within a range of 60±10 degrees with respect to the Y-axis direction.

Table 10 shows the fourth voltage application condition and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The fourth voltage application condition shown in Table 10 is a condition in which the second electrodes E12 and E22 are turned on (ON) in the first liquid crystal panel 1021 and the second liquid crystal panel 1022 to align the liquid crystal molecules with a horizontal electric field, and the first electrodes E11 and E21 are turned off (OFF). In the third to sixth liquid crystal panels 1023, 1024, 1025, and 1026, the first electrodes E31, E41, E51, and E61 and the second electrodes E32, E42, E52, and E62 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the second substrates S12 and S22 of the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are diffused in the X-axis direction. In other words, under the fourth voltage application condition, a line light distribution (L4) is formed in which the incident light from the light source is diffused once in the X-axis direction.

Table 11 shows the fifth voltage application condition and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The fifth voltage application condition shown in Table 11 is a condition in which the second electrodes E32 and E42 are turned on (ON) in the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a transverse electric field, and the first electrodes E31 and E41 are turned off (OFF). In the first liquid crystal panel 1021, the second liquid crystal panel 1022, the fifth liquid crystal panel 1025, and the sixth liquid crystal panel 1026, the first electrodes E11, E21, E51, E61 and the second electrodes E12, E22, E52, E62 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment films of the second substrates S32 and S42 of the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are diffused in a direction tilted within a range of 30±10 degrees with respect to the X-axis direction. That is, under the fifth voltage application condition, a line light distribution (L5) is formed in which the incident light from the light source is diffused once in a direction tilted within a range of 30±10 degrees with respect to the X-axis direction.

Table 12 shows the sixth voltage application condition and the state in which the polarized light components are diffused in each liquid crystal panel in this embodiment.

The sixth voltage application condition shown in Table 12 is a condition in which the second electrodes E52 and E62 are turned on (ON) in the fifth liquid crystal panel 1025 and the sixth liquid crystal panel 1026 to align the liquid crystal molecules with a transverse electric field, and the first electrodes E51 and E61 are turned off (OFF). In the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024, the first electrodes E11, E21, E31, and E41 and the second electrodes E12, E22, E32, and E42 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment films of the second substrates S52 and S62 of the fifth liquid crystal panel 1025 and the sixth liquid crystal panel 1026 are diffused in a direction tilted within a range of 60±10 degrees with respect to the X-axis direction. That is, under the sixth voltage application condition, a line light distribution (L6) is formed in which the incident light from the light source is diffused once in a direction tilted within a range of 60±10 degrees with respect to the X-axis direction.

17 shows the light distribution patterns formed under the first to sixth voltage application conditions. Note that FIG. 17 shows an example in which the first liquid crystal panel 1021 and the second liquid crystal panel 1022 are arranged in a rotated state within a range of 45±10 degrees relative to the wall surface 301. In accordance with this arrangement, the third liquid crystal panel 1023 and the fourth liquid crystal panel 1024 are further rotated within a range of 30±10 degrees relative to the first liquid crystal panel 1021 and the second liquid crystal panel 1022, and the fifth liquid crystal panel 1025 and the sixth liquid crystal panel 1026 are further rotated within a range of 60±10 degrees. Under the first voltage application condition, a line light distribution L1 extending in the Y-axis direction is formed, under the second voltage application condition, a line light distribution L2 extending in a direction inclined within a range of 30±10 degrees relative to the Y-axis direction is formed, and under the third voltage application condition, a line light distribution L3 extending in a direction inclined within a range of 60±10 degrees relative to the Y-axis direction is formed. Furthermore, under the fourth voltage application condition, a line light distribution L4 extending in the X-axis direction is formed, under the fifth voltage application condition, a line light distribution L5 extending in a direction tilted in the range of 30±10 degrees with respect to the X-axis direction is formed, and under the sixth voltage application condition, a line light distribution L6 extending in a direction tilted in the range of 60±10 degrees with respect to the X-axis direction is formed.

Of these six line light distributions L1, L2, L3, L4, L5, and L6, at least four line light distributions L1, L2, L3, and L4 are irradiated onto the wall surface 301, but since the directions in which the distributed light extends are different, more light irradiation areas can be formed than in the second embodiment. In this way, among the first to sixth liquid crystal panels 1021, 1022, 1023, 1024, 1025, and 1026, the third and fourth liquid crystal panels 1023 and 1024 are rotated within a range of 30±10 degrees, and the fifth and sixth liquid crystal panels 1025 and 1026 are rotated within a range of 60±10 degrees, thereby increasing the number of line light distributions irradiated onto the wall surface 301. The first to sixth voltage application conditions are driven for each liquid crystal panel as in the first embodiment, but the order of the voltage application conditions is arbitrary, and the voltages can be applied in any order, not limited to the ascending order from the first to the sixth.

In the lighting device 200 according to this embodiment, two of the six liquid crystal panels that make up the liquid crystal light control element 100 are rotated within a range of 30±10 degrees, and the other two are rotated within a range of 60±10 degrees, thereby increasing the number of linear light distributions that are irradiated onto the wall surface 301 and ceiling 302. This configuration can provide more indirect lighting to enhance the effect of the indoor space.

[Fourth embodiment]
The lighting device 200 according to this embodiment shows an example in which the configuration of the electrodes of the liquid crystal panel constituting the liquid crystal light control element 100 is different from that of the first embodiment. Specifically, in the first embodiment, the stripe patterns of the first and second electrodes of the liquid crystal panel are orthogonal to each other, but in this embodiment, the first and second electrodes of the liquid crystal panel are arranged to intersect at an angle of 45±10 degrees.

FIG. 18 shows the configuration of the liquid crystal light control element 100 according to this embodiment. The liquid crystal light control element 100 is composed of four liquid crystal panels (first liquid crystal panel 1021, second liquid crystal panel 1022, third liquid crystal panel 1023, and fourth liquid crystal panel 1024), which are arranged in a stacked manner in the Z-axis direction, as in the first embodiment. However, this embodiment differs from the first embodiment in that the second electrodes E12 and E32 of the first liquid crystal panel 1021 and the third liquid crystal panel 1023 are rotated within a range of 45±10 degrees relative to the first electrodes E11 and E31, and the first electrodes E31 and E41 of the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 are rotated within a range of 45±10 degrees relative to the second electrodes E32 and E42.

As shown in FIG. 18, the alignment directions ALD1 and ALD2 of the alignment film also intersect at an angle of 45±10 degrees. Therefore, the angle at which the first polarized component PL1 and the second polarized component PL2 are rotated when passing through each liquid crystal panel is in the range of 45±10 degrees. Below, Tables 13 to 15 show the voltage application conditions when such a liquid crystal panel is used.

Table 13 shows the first voltage application conditions according to this embodiment and the state in which the polarized light components are diffused in each liquid crystal panel.

The first voltage application condition shown in Table 13 is a condition in which the first electrodes E11 and E31 are turned on (ON) in the first liquid crystal panel 1021 and the third liquid crystal panel 1023 to align the liquid crystal molecules in a transverse electric field, and the second electrodes E12 and E32 are turned off (OFF). For the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024, the first electrodes E21 and E41 and the second electrodes E22 and E42 are all turned off (OFF). Under these conditions, the incident light is diffused in the Y-axis direction by the first electrode E11 of the first liquid crystal panel 1021, and is also diffused in the Y-axis direction by the first electrode E31 of the third liquid crystal panel 1023. In other words, under the first voltage application condition, a linear light distribution (L1) is formed in which the incident light from the light source is diffused in the Y-axis direction.

Table 14 shows the second voltage application conditions according to this embodiment and the state in which the polarized light components are diffused in each liquid crystal panel.

The second voltage application conditions shown in Table 14 are such that in the first liquid crystal panel 1021 and the third liquid crystal panel 1023, the second electrodes E12 and E32 are turned on (ON) to align the liquid crystal molecules with a horizontal electric field, and the first electrodes E11 and E31 are turned off (OFF), and in the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024, the first electrodes E21 and E41 are turned on (ON) to align the liquid crystal molecules with a horizontal electric field, and the second electrodes E22 and E42 are turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment films of the second substrates S12 and S32 of the first liquid crystal panel 1021 and the third liquid crystal panel 1023 and the first substrates S21 and S41 of the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 are diffused in a direction tilted 45 degrees with respect to the Y-axis direction. That is, a line light distribution (L2) is formed in which the incident light from the light source is diffused in a direction tilted at 45 degrees with respect to the Y-axis direction. Note that the direction in which the line light distribution (L2) extends will be within a range of 45±10 degrees with respect to the Y-axis direction depending on the rotation angle of the liquid crystal panel.

Table 15 shows the third voltage application condition according to this embodiment and the state in which the polarized light component is diffused in each liquid crystal panel.

The second voltage application condition shown in Table 15 is a condition in which the second electrodes E22 and E42 are turned on (ON) in the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a transverse electric field, and the first electrodes E21 and E41 are turned off (OFF). In the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024, the first electrodes E11 and E31 and the second electrodes E12 and E32 are all turned off (OFF). Under such conditions, among the incident light, the polarized component having the same direction as the orientation direction of the alignment film of the second substrate S22 and S42 of the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 is diffused in the X-axis direction. That is, under the third voltage application condition, a line light distribution (L3) in which the incident light from the light source is diffused in the X-axis direction with respect to the X-axis direction is formed.

19 shows the light distribution patterns formed under the first to third voltage application conditions. Note that FIG. 19 shows a state in which the first liquid crystal panel 1021 and the third liquid crystal panel 1023 are arranged in a state rotated within a range of 45±10 degrees relative to the wall surface 301, and the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 are arranged in a state rotated within a range of 45±10 degrees relative to the first liquid crystal panel 1021 and the third liquid crystal panel 1023. Under the first voltage application condition, a line light distribution L1 extending in the Y-axis direction is formed, under the second voltage application condition, a line light distribution L2 extending in a direction inclined within a range of 45±10 degrees relative to the Y-axis direction is formed, and under the third voltage application condition, a line light distribution L3 extending in the X-axis direction is formed. These three line light distributions L1, L2, and L3 are irradiated onto the wall surface 301, but the irradiated positions are different because the directions in which the distributed light extends are different. In this way, among the first to fourth liquid crystal panels 1021, 1022, 1023, and 1024 arranged so that the extension directions of the strip electrodes of the first electrode and the second electrode intersect at an angle of 45±10 degrees, the first and third liquid crystal panels 1021 and 1023 are rotated within a range of 45±10 degrees to form three line light distributions and irradiate the wall surface 301. Note that the first to third voltage application conditions are driven for each liquid crystal panel as in the first embodiment, but the order of the voltage application conditions is arbitrary, and there is no limit to the order in which the first to third voltage application conditions appear.

In the lighting device 200 according to this embodiment, the strip patterns of the first and second electrodes of the liquid crystal panels constituting the liquid crystal light control element 100 are arranged so as to intersect at a 45 degree angle. By stacking four such liquid crystal panels and rotating the second liquid crystal panel 1022 and the fourth liquid crystal panel 1024 by 45 degrees relative to the first liquid crystal panel 1021 and the third liquid crystal panel 1023, it is possible to form a line light distribution extending in three directions. This configuration can also provide indirect lighting to enhance the effect of creating an indoor space.

[Fifth embodiment]
This embodiment shows an example of a light distribution pattern of an illumination device 200 obtained by a liquid crystal light control element 100 using six liquid crystal panels and having electrodes with a different configuration from that of the third embodiment.

FIG. 20 shows a configuration in which the liquid crystal light control element 100 according to this embodiment is composed of six liquid crystal panels (a first liquid crystal panel 1021, a second liquid crystal panel 1022, a third liquid crystal panel 1023, a fourth liquid crystal panel 1024, a fifth liquid crystal panel 1025, and a sixth liquid crystal panel 1026) that are stacked in the Z-axis direction.

The first liquid crystal panel 1024 is arranged such that the direction in which the strip electrodes of the second electrode E12 extend intersects with the direction in which the strip electrodes of the first electrode E11 extend at an angle of 30±10 degrees. The second to sixth liquid crystal panels 1022, 1023, 1024, 1025, and 1026 have a similar configuration. The second liquid crystal panel 1022 is rotated relative to the first liquid crystal panel 1021 within a range of 30±10 degrees, and the third liquid crystal panel 1023 is rotated relative to the second liquid crystal panel 1022 within a range of 30±10 degrees (the third liquid crystal panel 1023 is rotated relative to the first liquid crystal panel 1021 within a range of 60±10 degrees). In addition, the fifth liquid crystal panel 1025 is rotated within a range of 30±10 degrees relative to the fourth liquid crystal panel 1024, and the sixth liquid crystal panel 1026 is rotated within a range of 30±10 degrees relative to the fifth liquid crystal panel 1025 (the sixth liquid crystal panel 1026 is rotated within a range of 60±10 degrees relative to the fourth liquid crystal panel 1024). The first liquid crystal panel 1021 and the fourth liquid crystal panel 1024 are arranged so that the strip electrodes of the first electrodes E11 and E41 and the strip electrodes of the second electrodes E12 and E42 extend in the same direction.

With this arrangement, the direction in which the strip-shaped electrodes of the first electrodes E21, E51 of the second and fifth liquid crystal panels 1022, 1025 extend is inclined within a range of 30±10 degrees relative to the first electrodes E11, E41 of the first and fourth liquid crystal panels 1021, 1024, and the direction in which the strip-shaped electrodes of the first electrodes E31, E61 of the third and sixth liquid crystal panels 1023, 1026 extend is inclined within a range of 60±10 degrees. Similarly, the direction in which the strip electrodes of the second electrodes E22, E52 of the second and fifth liquid crystal panels 1022, 1025 extend is inclined within a range of 30±10 degrees relative to the second electrodes E12, E42 of the first and fourth liquid crystal panels 1021, 1024, and the direction in which the strip electrodes of the second electrodes E32, E62 of the third and sixth liquid crystal panels 1023, 1026 extend is inclined within a range of 30±10 degrees. The same is true for the alignment directions ALD1, ALD2 of the alignment films and the alignment direction of the liquid crystal molecules LCM.

Table 16 shows the first voltage application conditions according to this embodiment and the state in which the polarized light components are diffused in each liquid crystal panel.

The first voltage application condition shown in Table 16 is a condition in which the first electrodes E11 and E41 are turned on (ON) in the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024 to align the liquid crystal molecules with a horizontal electric field, and the second electrodes E12 and E42 are turned off (OFF). In the second liquid crystal panel 1022, the third liquid crystal panel 1023, the fifth liquid crystal panel 1025, and the sixth liquid crystal panel 1026, the first electrodes E21, E31, E51, and E61 and the second electrodes E22, E32, E52, and E62 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the first substrates S11 and S41 of the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024 are diffused in the Y-axis direction. In other words, under the first voltage application condition, a linear light distribution (L1) is formed in which the incident light from the light source is diffused in the Y-axis direction.

Table 17 shows the second voltage application conditions according to this embodiment and the state in which the polarized light components are diffused in each liquid crystal panel.

The second voltage application condition shown in Table 17 is a condition in which the second electrodes E32 and E62 are turned on (ON) in the third liquid crystal panel 1023 and the sixth liquid crystal panel 1026 to align the liquid crystal molecules with a horizontal electric field, and the first electrodes E31 and E61 are turned off (OFF). For the first liquid crystal panel 1021, the second liquid crystal panel 1022, the fourth liquid crystal panel 1024, and the fifth liquid crystal panel 1025, the first electrodes E11, E21, E41, and E51 and the second electrodes E12, E22, E42, and E52 are all turned off (OFF). Under these conditions, the polarized components of the incident light that are oriented in the same direction as the orientation direction of the alignment film of the second substrates S32 and S62 of the third liquid crystal panel 1023 and the sixth liquid crystal panel 1026 are diffused in the X-axis direction. In other words, under the second voltage application condition, a linear light distribution (L2) is formed in which the incident light from the light source is diffused in the X-axis direction.

Table 18 shows the third voltage application condition according to this embodiment and the state in which the polarized light component is diffused in each liquid crystal panel.

The third voltage application condition shown in Table 18 is a condition in which the second electrodes E12, E42 of the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024 are turned on (ON) to align the liquid crystal molecules with a transverse electric field, the first electrodes E11, E41 are turned off, the first electrodes E21, E51 of the second liquid crystal panel 1022 and the fifth liquid crystal panel 1025 are turned on (ON) to align the liquid crystal molecules with a transverse electric field, and the second electrodes E22, E52 are turned off. For the third liquid crystal panel 1023 and the sixth liquid crystal panel, the first electrodes E31, E61 and the second electrodes E32, E62 are all turned off (OFF). Under these conditions, the polarized light components having the same orientation as the orientation direction of the alignment film of the second substrates S12 and S42 of the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024 are diffused in a direction of 30±10 degrees with respect to the Y-axis direction, and the polarized light components having the same orientation as the orientation direction of the alignment film of the first substrates S21 and S51 of the second liquid crystal panel 1022 and the fifth liquid crystal panel 1025 are diffused in a direction of 30±10 degrees with respect to the Y-axis direction. In other words, under the third voltage application condition, a line light distribution (L3) is formed in which the incident light from the light source is diffused in a direction of 30±10 degrees with respect to the Y-axis direction.

Table 19 shows the fourth voltage application condition according to this embodiment and the state in which the polarized light components are diffused in each liquid crystal panel.

The fourth voltage application condition shown in Table 19 is a condition in which, in the second liquid crystal panel 1022 and the fifth liquid crystal panel 1025, the second electrodes E22 and E52 are turned on (ON) to align the liquid crystal molecules with a transverse electric field and the first electrodes E21 and E51 are turned off (OFF), and in the third liquid crystal panel 1023 and the sixth liquid crystal panel 1026, the first electrodes E31 and E61 are turned on (ON) to align the liquid crystal molecules with a transverse electric field and the second electrodes E32 and E62 are turned off (OFF). For the first liquid crystal panel 1021 and the fourth liquid crystal panel 1024, the first electrodes E11 and E41 and the second electrodes E12 and E42 are all turned off (OFF). Under these conditions, the polarized light components in the same direction as the orientation direction of the alignment film of the second substrates S22 and S52 of the second liquid crystal panel 1022 and the fifth liquid crystal panel 1025 are diffused in a direction of 60±10 degrees with respect to the Y-axis direction, and the polarized light components in the same direction as the orientation direction of the alignment film of the first substrates S31 and S61 of the third liquid crystal panel 1023 and the sixth liquid crystal panel 1026 are diffused in a direction of 60±10 degrees with respect to the Y-axis direction. In other words, under the fourth voltage application condition, a line light distribution (L4) is formed in which the incident light from the light source is diffused in a direction of 60±10 degrees with respect to the Y-axis direction.

FIG. 21 shows the light distribution patterns formed under the first to fourth voltage application conditions. Note that FIG. 21 shows the state in which the first liquid crystal panel 1021 is arranged in a state rotated 45 degrees with respect to the wall surface 301 in the liquid crystal light control element 100 shown in FIG. 20. Under the first voltage application condition, a line light distribution L1 extending in the Y-axis direction is formed, under the second voltage application condition, a line light distribution L2 extending in the X-axis direction is formed, under the third voltage application condition, a line light distribution L3 extending in a direction tilted in the range of 30±10 degrees with respect to the Y-axis direction is formed, and under the fourth voltage application condition, a line light distribution L4 extending in a direction tilted in the range of 60±degrees with respect to the Y-axis direction is formed. These four line light distributions L1, L2, L3, and L4 are irradiated onto the wall surface 301, but the irradiated positions are different because the directions in which the distributed light extends are different. In this way, by stacking the liquid crystal panels in such a way that the strip patterns of the first and second electrodes intersect at an angle of 30 degrees, four line light distributions can be formed and irradiated onto the wall surface 301. Note that the first to fourth voltage application conditions are driven for each liquid crystal panel as in the first embodiment, but the order of the voltage application conditions is arbitrary, and there is no limit to the order in which the first to fourth voltage application conditions appear.

In the lighting device 200 according to this embodiment, the strip patterns of the first and second electrodes of the liquid crystal panel that constitutes the liquid crystal light control element 100 are arranged so that they intersect at an angle of 30 degrees. This arrangement makes it possible to form a line light distribution that extends in four directions. This configuration also makes it possible to enhance the effect of the indirect lighting in the indoor space.

The various configurations of the lighting device exemplified as one embodiment of the present invention can be combined as appropriate as long as they are not mutually inconsistent. Furthermore, lighting devices disclosed in this specification and drawings that are modified by a person skilled in the art with appropriate additions, deletions, or design changes to components, or that include additions, omissions, or changes to conditions of processes, are also included within the scope of the present invention as long as they incorporate the essence of the present invention.

　Even if there are other effects and advantages different from those brought about by the aspects of the embodiments disclosed in this specification, if they are clear from the description in this specification or can be easily predicted by a person skilled in the art, they are naturally understood to be brought about by the present invention.

100: Liquid crystal light control element, 102: Liquid crystal panel, 1021: First liquid crystal panel, 1022: Second liquid crystal panel, 1023: Third liquid crystal panel, 1024: Fourth liquid crystal panel, 1025: Fifth liquid crystal panel, 1026: Sixth liquid crystal panel, 200: Lighting device, 202: Housing, 2021: Reference surface, 2022: Sign, 2023: Light outlet, 204: Light source, 206: Control circuit, 301: Wall, Wall surface, 302: Ceiling, AL11: First alignment film, AL12: Second alignment film, ALD1: Alignment direction, ALD2: Alignment direction, E11: First electrode, E11A: First strip electrode, E11B : Second strip electrode, E12: Second electrode, E12A: Third strip electrode, E12B: Fourth strip electrode, LC1: Liquid crystal layer (first liquid crystal layer), LCM: Liquid crystal molecule, PE11: First power supply line, PE12: Second power supply line, PE13: Third power supply line, PE14: Fourth power supply line, PE15: Fifth power supply line, PE16: Sixth power supply line, PT11: First power supply terminal, PT12: Second power supply terminal, PT13: Third power supply terminal, PT14: Fourth power supply terminal, S11: First substrate, S12: Second substrate, T11: First connection terminal, T12: Second connection terminal, T13: Third connection terminal, T14: Fourth connection terminal

Claims (12)

A liquid crystal light control element in which a plurality of liquid crystal panels are stacked;
a housing in which a light source is housed, the housing having a light exit port, and an exterior that allows a reference direction to be identified;
Each of the plurality of liquid crystal panels is
A first substrate;
a second substrate facing the first substrate;
a liquid crystal layer between the first substrate and the second substrate;
a first strip-shaped electrode provided on the first substrate and extending in a first direction; and a second strip-shaped electrode disposed parallel to the first strip-shaped electrode;
a third strip-shaped electrode provided on the second substrate and extending in a second direction intersecting the first direction; and a fourth strip-shaped electrode adjacent to the third strip-shaped electrode;
having
the liquid crystal light control element is disposed so as to overlap the light exit port,
A lighting device characterized in that, when the housing is arranged with the reference direction facing a wall surface, the direction in which the first strip electrode and the second strip electrode extend, and the direction in which the third and fourth strip electrodes extend, of at least one of the multiple liquid crystal panels intersect with the normal direction of the wall surface. The lighting device according to claim 1, wherein the housing has a cylindrical body with a part of the side surface molded into a flat surface, and the flat surface forms a reference surface for identifying the reference direction. The lighting device according to claim 1, wherein the housing has a trapezoidal cross-sectional shape in a plan view, and one of the side surfaces corresponding to two parallel sides of the trapezoid forms a reference surface for identifying the reference direction. The lighting device according to claim 1, wherein the housing has a protrusion protruding from a side surface, the protrusion being a mark for identifying the reference direction. The lighting device according to claim 1, wherein the housing has a recess in which the side is partially recessed, and the recess is a mark that identifies the reference direction. The lighting device according to claim 1, wherein the housing is provided with a marking that indicates the reference direction and is displayed using letters, figures, or symbols. the plurality of liquid crystal panels include a first liquid crystal panel, a second liquid crystal panel, a third liquid crystal panel, and a fourth liquid crystal panel;
2 . The lighting device according to claim 1 , wherein in each of the first to fourth liquid crystal panels, the first and second strip-shaped electrodes and the third and fourth strip-shaped electrodes are arranged so as to be perpendicular to each other. the plurality of liquid crystal panels include a first liquid crystal panel, a second liquid crystal panel, a third liquid crystal panel, and a fourth liquid crystal panel;
In each of the first to fourth liquid crystal panels, the first and second strip electrodes are arranged so as to be perpendicular to the third and fourth strip electrodes,
2. The lighting device according to claim 1, wherein the third and fourth liquid crystal panels are arranged rotated 45 degrees with respect to the first and second liquid crystal panels. the plurality of liquid crystal panels include a first liquid crystal panel, a second liquid crystal panel, a third liquid crystal panel, a fourth liquid crystal panel, a fifth liquid crystal panel, and a sixth liquid crystal panel;
In each of the first to sixth liquid crystal panels, the first and second strip electrodes are arranged so as to be perpendicular to the third and fourth strip electrodes,
2. The lighting device of claim 1, wherein the third and fourth liquid crystal panels are rotated within a range of 30±10 degrees relative to the first and second liquid crystal panels, and the fifth and sixth liquid crystal panels are rotated within a range of 60±10 degrees. the plurality of liquid crystal panels include a first liquid crystal panel, a second liquid crystal panel, a third liquid crystal panel, and a fourth liquid crystal panel;
Each of the first to fourth liquid crystal panels is arranged such that the first strip electrodes and the second strip electrodes intersect with the third strip electrodes and the fourth strip electrodes at an angle in a range of 45±10 degrees,
2. The lighting device according to claim 1, wherein the third and fourth liquid crystal panels are arranged rotated 45 degrees with respect to the first and third liquid crystal panels. the plurality of liquid crystal panels include a first liquid crystal panel, a second liquid crystal panel, a third liquid crystal panel, a fourth liquid crystal panel, a fifth liquid crystal panel, and a sixth liquid crystal panel;
Each of the first to sixth liquid crystal panels is arranged such that the first strip electrodes and the second strip electrodes intersect with the third strip electrodes and the fourth strip electrodes at an angle of 30±10 degrees;
2. The lighting device of claim 1, wherein the second and fifth liquid crystal panels are rotated within a range of 30±10 degrees relative to the first and fourth liquid crystal panels, and the third and sixth liquid crystal panels are rotated within a range of 60±10 degrees relative to the first and fourth liquid crystal panels. The lighting device according to claim 1, wherein the liquid crystal light control element emits at least light of a first light distribution pattern extending in a first direction and light of a second light distribution pattern extending in a second direction intersecting the first direction.

Images