WO2016035239A1 - Display control system - Google Patents

Abstract

A display control system that satisfies condition (1) is provided with a display device (120) and a reader device (digital pen (110)). The display device includes a display unit, a reflective sheet having a reflective layer (cover layer) with a unit shape of a substantially triangular pyramidal structure combining three triangular faces, and a position information pattern (mark) indicating position information. The reader device reads the position information pattern by recognizing, via an image-capturing unit (115), light irradiated from an illumination unit (111) and reflected by the reflective sheet. sin^-1((n1/n2)sin(tan^-1(Sl/2hl)) < |2.25θt - 202.5| < sin^-1(n1/n2)...(1) θt: Angle formed by a side configured by the joining of two of the triangular faces of the unit shape and the other triangular face. n1: Refractive index of a space in which the reader device is used. n2: Refractive index of the cover layer of the reflective sheet. Sl: Diameter of a light irradiation opening of the illumination unit. hl: Distance from the illumination unit to the center of an image-captured range of the image-capturing unit on the reflective sheet.

Description

Display control system

This disclosure relates to a display control system.

Patent Document 1 discloses a display device that recursively reflects incident light from the outside and returns it to the light source direction. The display device includes a display device body, a retroreflective structure, and an optical member having an antireflection film that covers the retroreflective structure. Thereby, it is possible to prevent the incident light from the outside from reaching the inspector.

JP 2011-107294 A

This disclosure is intended to provide a display control system that can reduce power consumption and improve reading accuracy in a reading apparatus.

A display control system according to the present disclosure includes a display unit, a reflection sheet including a reflection layer having a unit shape of a substantially triangular pyramid structure in which three triangular surfaces are combined, and a reflection unit provided on the reflection direction side of the reflection sheet. A position information pattern indicating a position information pattern in the image display unit, a lighting device and an imaging unit. The imaging unit recognizes the light irradiated from the lighting unit and reflected from the reflection sheet. The reflection sheet includes a cover layer provided on the reflection direction side of the reflection layer, and satisfies the following formula (1).

sin ⁻¹ ((n1 / n2) sin (tan ⁻¹ (Sl / 2hl)) <| 2.25θt-202.5 | <sin ⁻¹ (n1 / n2) (1)

Here, θt: angle formed by the side formed by the contact of two triangular surfaces of the unit shape and the surface of the other triangle n1: refractive index of the space in which the reader is used n2: refractive index of the cover layer Sl: the above Diameter of light irradiation port of illumination unit hl: Distance from the illumination unit to the center of the imaging range of the imaging unit on the reflection sheet.

The display control system according to the present disclosure can improve reading accuracy in the input device while reducing power consumption.

FIG. 1 is a schematic diagram showing a display control system according to the first embodiment. FIG. 2 is a block diagram showing a configuration of the display control system in the first embodiment. FIG. 3 is an explanatory diagram illustrating a schematic configuration of the digital pen and the display device according to the first embodiment. FIG. 4 is a cross-sectional configuration diagram of the display device in the first embodiment. FIG. 5A is an enlarged view showing a surface shape of the reflection sheet in the first exemplary embodiment. 5B is a cross-sectional view taken along the line bb in FIG. 5A. FIG. 6 is an explanatory diagram for explaining an optical operation of the display control system according to the first embodiment. FIG. 7 is a cross-sectional view showing the configuration of the reflection sheet in the second embodiment. FIG. 8 is a cross-sectional view showing a configuration of a modified example of the reflection sheet in the second embodiment. FIG. 9 is a cross-sectional view showing the configuration of the reflection sheet in the third embodiment. FIG. 10 is a cross-sectional view showing the configuration of the reflection sheet in the fourth embodiment. FIG. 11A is an enlarged view showing the surface shape of the reflection sheet in the fifth embodiment. FIG. 11B is a cross-sectional view taken along the line bb in FIG. 11A. FIG. 12A is an enlarged view showing a surface shape of a modified example of the reflection sheet in the fifth embodiment. 12B is a cross-sectional view taken along the line bb in FIG. 12A. FIG. 13A is an enlarged view showing the surface shape of the reflection sheet in the sixth embodiment. 13B is a cross-sectional view taken along the line bb in FIG. 13A.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

The accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the claimed subject matter.

(Embodiment 1)
The first embodiment will be described below with reference to FIGS.

[1. Constitution]
[1-1. overall structure]
FIG. 1 is a schematic diagram illustrating an appearance of a display control system 100 according to the first embodiment. The display control system 100 includes an optical digital pen 110 and a display device 120. The digital pen 110 is an example of a reading device.

Although the details will be described later, the display device 120 is a liquid crystal display, and can display various images on the display unit 121. In addition, the display device 120 is provided with a mark 131 representing position information on the display unit 121. The digital pen 110 optically reads the mark 131 to detect information on the position of the digital pen 110 on the display surface of the display unit 121 (hereinafter referred to as “position information”), and displays the position information on the display device 120. Send to. That is, the mark 131 is a position information pattern.

When the position information is input from the digital pen 110, the display device 120 performs various display controls based on the position information. For example, the display device 120 continuously displays dots on the display unit 121 according to the trajectory of the digital pen 110. Thereby, it is possible to input characters, figures, and the like on the display unit 121 using the digital pen 110 by handwriting. Alternatively, the display device 120 continuously erases points on the display unit 121 according to the trajectory of the digital pen 110. Thereby, the character and figure of the display part 121 can be erased using the digital pen 110 like an eraser. That is, the digital pen 110 functions as a reading device and also functions as an input device of the display control system 100.

FIG. 2 is a block diagram showing a schematic configuration of the display control system 100.

The display device 120 includes a receiving unit 122 that receives a signal from the outside, a microcomputer 123 that controls the entire display device 120, and a display unit 121 that displays an image.

The receiving unit 122 receives a signal transmitted from the digital pen 110. The signal received by the receiving unit 122 is sent to the microcomputer 123.

The microcomputer 123 includes a CPU, a memory, and the like, and a program for operating the CPU is also mounted. For example, the microcomputer 123 controls the display unit 121 based on a signal transmitted from the digital pen 110 to change the content displayed on the display unit 121.

The digital pen 110 includes an illumination unit 111, an imaging unit 115, a pen control unit 116, and a transmission unit 117.

The illumination unit 111 is, for example, an LED (Light Emitting Diode) that emits infrared light.

The imaging unit 115 includes a lens system 115a and an imaging element 115b. The light imaged through the lens system 115a is photoelectrically converted by the image sensor 115b into an image signal. The image sensor 115 b transmits an image signal to the pen control unit 116.

The pen control unit 116 includes a specifying unit 116a and a microcomputer 116b.

The identifying unit 116 a identifies the position of the digital pen 110 on the display unit 121 based on the image signal from the imaging unit 115. Specifically, the specifying unit 116a acquires the position information of the mark 131 illuminated by the illumination unit 111 based on the image signal acquired by the imaging unit 115, and the digital on the display unit 121 based on the position information. The position of the pen 110 is specified. The position information of the digital pen 110 specified by the specifying unit 116a is sent to the microcomputer 116b.

The microcomputer 116b is composed of a CPU, a memory, and the like, and a program for operating the CPU is also mounted. For example, the microcomputer 116b transmits the position information of the digital pen 110 sent from the specifying unit 116a to the display device 120 via the transmission unit 117.

FIG. 3 is an explanatory diagram showing a schematic configuration of the digital pen 110 and the display device 120.

The digital pen 110 illustrated in FIG. 3 includes an imaging unit 115, an illumination unit 111, and a pen tip unit 119. The imaging unit 115 is supported by the pen tip 119 so that its optical axis G1 is parallel to the extending direction of the pen tip 119. The imaging unit 115 uses the tip end side of the pen tip 119 as an imaging range. The illumination unit 111 is supported by the pen tip 119 via a support body (not shown) so that the optical axis G2 of the illumination unit 111 is different from the optical axis G1 of the imaging unit 115. Specifically, the optical axis G1 of the imaging unit and the optical axis G2 of the illumination unit 111 intersect on the display unit 121 when the pen tip unit 119 comes into contact with the display unit 121 of the display device 120. The installation positions of the imaging unit 115 and the illumination unit 111 are adjusted.

The state where the pen tip 119 of the digital pen 110 is in contact with the display unit 121 is referred to as a use state. In the use state, the distance from the center of the imaging range of the imaging unit 115 on the display unit 121 to the illumination unit 111 is hl [mm], and the diameter of the light irradiation port of the illumination unit 111 is Sl [mm]. The light irradiation port of the illuminating unit 111 is an opening through which infrared light is emitted, and the diameter of this opening is the diameter of the light emitting port. Further, the distance from the center of the imaging range in use to the imaging unit 115 is hc [mm], and the angle of view of the imaging unit 115 is θc [degrees].

The display unit 121 uses a liquid crystal display panel.

FIG. 4 is a cross-sectional view showing a schematic configuration of the display unit 121. A position information pattern sheet 130 having a plurality of marks 131 for the digital pen 110 to read position information is disposed on the display unit 121.

The position information pattern sheet 130 includes a plurality of marks 131 forming an arbitrary pattern, a resin-made transparent base film 132, and a resin-made light-transmissive cover film 133. On the base film 132, a plurality of marks 131 having a geometric shape such as a circular shape or a rectangular shape are formed in a predetermined arrangement pattern. A cover film 133 is laminated so as to cover the mark 131 and the base film 132. The refractive index of the position information pattern sheet 130 can be adjusted by adjusting the material and thickness of the cover film 133.

In Embodiment 1, the mark 131 of the position information pattern sheet 130 is formed of a material that absorbs light of a specific wavelength. Specifically, the mark 131 is formed of a material that transmits visible light and absorbs infrared light 113. Thereby, the influence on the visibility of the color display image of the visible light area displayed on the display unit 121 is reduced.

[1-2. Reflective sheet]
A reflective sheet 104 having retroreflectivity is provided between the position information pattern sheet 130 and the display unit 121. The reflection sheet 104 is a reflection sheet having retroreflectivity that reflects the infrared light 113 emitted from the illumination unit 111 toward the imaging unit 115.

The reflection sheet 104 includes a unit shape 141, a base layer 143, and a cover layer 142.

Unit shapes 141 having a substantially triangular pyramid structure having three triangular faces are formed in a predetermined arrangement pattern on the surface of the base layer 143 on the reflection direction side. The unit shape 141 has a shape in which one surface of the triangular pyramid is opened. Specifically, the unit shape 141 has a substantially triangular pyramid shape with an open surface on the reflection direction side. The unit shape 141 has a substantially corner cube structure. A light-transmitting cover layer 142 for adjusting the refractive index is formed so as to cover the unit shape 141 and be filled in the unit shape 141. Of the cover layer 142, the portion filled in the unit shape 141 (filled portion 141 t) has a shape equivalent to the unit shape 141.

The base layer 143 is a reflective layer. Specifically, the base layer 143 is formed of a resin light-transmitting film, and an infrared reflection layer (not shown) is formed at a portion overlapping the unit shape 141, that is, at the boundary between the unit shape 141 and the filling portion 141t. Are stacked. Since the infrared reflection layer transmits visible light and reflects infrared light, it does not affect visible light other than a specific wavelength, and the quality of the display device 120 is improved.

Note that the base layer 143 itself may be an infrared reflective layer. In this case, light is reflected at the boundary between the base layer 143 and the cover layer 142. If the infrared reflective layer is a metal film, it can be formed by a vapor deposition process. If the infrared reflective layer is a cholesteric liquid crystal, it can be easily and inexpensively formed by a coating process. In addition, if the infrared reflective layer is a dielectric multilayer film, it is possible to selectively reflect not only infrared light but also a specific wavelength, thus increasing the degree of freedom in design. In addition, if the infrared reflective layer is made of a material containing fine metal particles, it can be designed to reflect infrared light and diffuse light appropriately according to its particle shape and particle size. become. For the metal film and the metal fine particles, for example, a material having high transparency to visible light such as ITO or ZnO can be selected.

FIG. 5A is a schematic view of the reflection sheet 104 as viewed from above. 5B is a cross-sectional view taken along the line bb of the reflection sheet 104 in FIG. 5A.

In the unit shape 141, when the unit shape 141 is viewed from above, that is, when viewed in plan, the length of one side is L. When the unit shape 141 is a regular triangular pyramid shape and the opened one surface is a bottom surface of an equilateral triangle, the length of one side of the bottom surface is L. In addition, among the three triangular surfaces constituting the unit shape 141, an angle formed by the side L1 formed by the contact of the two triangular surfaces and the other triangular surface S1 is an angle θt [degree], and the unit The height (maximum thickness) of the shape 141 is d [mm]. Specifically, the height d is a distance from the lowest position of the unit shape 141 to the highest position. In the first embodiment, the angle θt is not 90 degrees unlike the conventional corner cube structure.

The angle θt of the unit shape 141 of the present disclosure is preferably an acute angle. By doing so, the incident infrared light 113 (see FIG. 6) is easily reflected a plurality of times inside the unit shape 141. Therefore, the infrared light 113 is easily retroreflected. On the contrary, when the angle θt is an obtuse angle, the infrared light 113 is easily reflected outside the reflection sheet 104 without being reflected a plurality of times inside the unit shape 141. Accordingly, the amount of retroreflected light is reduced. That is, the amount of light that can be captured by the imaging unit 115 is reduced.

L is the length of one side of the unit shape 141 when the reflection sheet 104 is viewed from the plane direction. The unit shape 141 is arranged so as to be densely laid on a plane using a rotated shape. However, there may be a gap that does not affect the reading performance of the digital pen 110.

The unit shape 141 is preferably smaller than the imaging range of the imaging unit 115. Furthermore, when the area when the unit shape 141 is viewed in plan is Mp, the area of the imaging range on the display unit 121 of the imaging unit 115 is Mc, and the number of effective pixels of the imaging unit 115 is Px, the following equation (a ) Is desirable. The area Mc may be the area of the imaging range on the reflection sheet 104 of the imaging unit 115.

Mp <Mc / (2 × Px) (a)

By doing so, since the plurality of unit shapes 141 are included in the captured image, the light amount unevenness is reduced.

[2. function]
The function of the display control system 100 configured as described above will be described below.

FIG. 6 is a diagram illustrating an optical operation of the display control system 100 according to the first embodiment. The infrared light 113 emitted from the illumination unit 111 of the digital pen 110 first enters the position information pattern sheet 130. At this time, in the position information pattern sheet 130, the infrared light 113 is absorbed at the position where the mark 131 is disposed. In the position where the mark 131 is not disposed, the infrared light 113 reaches the reflection sheet 104 having retroreflectivity.

The infrared light 113 that has reached the reflection sheet 104 is reflected by the retroreflectivity of the unit shape 141 and is reflected in the direction of the illumination unit 111. Here, the reflection angle can be varied according to the angle θt of the unit shape 141.

In Embodiment 1, the display control system 100 may be configured to satisfy the following expression.

sin ⁻¹ ((n1 / n2) sin (tan ⁻¹ (Sl / 2hl)) <| 2.25θt-202.5 | <sin ⁻¹ (n1 / n2) (1)

here,
θt: angle formed by a side formed by two triangular surfaces of the unit shape 141 and another triangular surface n1: refractive index of a space in which the digital pen 110 is used n2: refractive index of the cover layer 142 Sl: illumination unit 111 diameter of light emission port hl: distance from the illumination unit 111 to the center of the imaging range of the imaging unit 115 on the reflection sheet 104.

Equation (1) means that the angle at which the infrared light 113 incident on the display device 120 is reflected can be arbitrarily controlled by changing the angle θt. Furthermore, by configuring so that the angle θt satisfies the expression (1), the reflection angle is limited so that the incident light is not totally reflected on the emission surface of the reflection sheet 104, and outside the light emission port of the illumination unit 111. The infrared light 113 can be reflected. By reflecting the infrared light 113 outside the illumination unit 111, the imaging unit 115 can capture the infrared light 113. On the contrary, when the reflection sheet 104 has complete recursion, that is, when the infrared light 113 is reflected inside the light exit of the illumination unit 111, the reflected light toward the imaging unit 115 is reduced. The imaging unit 115 cannot be illuminated. Further, if the reflection angle increases to an extent that exceeds the upper limit of Expression (1), the reflection surface 104 is totally reflected based on Snell's law, and the infrared light 113 is less likely to face the imaging unit 115. Also in this case, the reading performance of the digital pen 110 is significantly reduced.

In addition to the equation (1), the display control system 100 desirably further configures the angle θt of the unit shape 141 so as to satisfy the following equation (2). By satisfying Expression (2), the imaging unit 115 can capture the infrared light 113 emitted from the illumination unit 111 more efficiently.

(Θl−tan ⁻¹ (Sl / 2hl)) − (θc−tan ⁻¹ ((hc / hl) tan θc)) ≦ sin ⁻¹ ((n2 / n1) sin | 2.25θt−202.5 |) ≦ (Θl + tan ⁻¹ (Sl / 2hl)) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (2)

here,
hc: distance from the center of the imaging range of the imaging unit 115 to the imaging unit 115 θl: an angle formed by the optical axis G2 of the illumination unit 111 and the optical axis G1 of the imaging unit 115 θc: a half angle of view of the imaging unit 115.

According to the positional relationship between the imaging unit 115 and the illumination unit 111, the reflection sheet 104 is configured so that the angle θt satisfies the expression (2), so that the infrared light 113 is efficiently reflected toward the imaging unit 115. be able to.

Further, the display control system 100 according to the first embodiment also exhibits the same effect as the expression (1) by satisfying the following expression (3).

sin ⁻¹ ((n1 / n2) sin (tan ⁻¹ (Sl / 2hl)) <| 62.65a ² −251.86a + 189.28 | <sin ⁻¹ (n1 / n2) (3)

here,
n1: Refractive index of the space where the digital pen 110 is used n2: Refractive index of the cover layer 142 Sl: Diameter of the light exit of the illumination unit 111 hl: From the illumination unit 111 to the imaging range of the imaging unit 115 on the reflection sheet 104 Distance to center a: Ratio of the length L of one side of the bottom surface of the unit shape 141 to the height d.

Expression (3) arbitrarily controls the angle at which the infrared light 113 incident on the display device 120 is reflected by changing the ratio between the length L of one side of the bottom surface of the unit shape 141 and the height d. Means you can.

Further, the display control system 100 according to the first embodiment exhibits the same effect as that of the formula (2) by satisfying the following formula (4) in addition to the formula (3).

(Θl−tan ⁻¹ (Sl / 2hl)) − (θc−tan ⁻¹ ((hc / hl) tan θc)) ≦ sin ⁻¹ ((n2 / n1) sin | 62.65a ² −251.86a + 189.28 |) ≦ (θl + tan ⁻¹ (Sl / 2hl)) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (4)

here,
hc: distance from the imaging center of the imaging range of the imaging unit 115 to the imaging unit 115 θl: an angle formed by the optical axis G2 of the illumination unit 111 and the optical axis G1 of the imaging unit 115 θc: a half angle of view of the imaging unit 115.

In order to satisfy Expression (4), the ratio of the length L of one side of the unit shape 141 to the height d is changed according to the positional relationship between the imaging unit 115 and the illuminating unit 111 to enter the display device 120. Infrared light 113 can be efficiently reflected by the imaging unit 115.

[3. effect]
In the display control system 100 according to the first embodiment, by configuring the reflection sheet 104 so that the angle θt satisfies the expression (1), the reflection angle is limited so that incident light is not totally reflected on the exit surface of the reflection sheet 104. However, the infrared light 113 can be reflected outside the illumination unit 111. The infrared light 113 can be captured by the imaging unit 115 by reflecting the infrared light 113 outside the illumination unit 111. Further, by setting the angle θt within the range of the expression (2), the light emitted from the illumination unit 111 can be efficiently delivered to the imaging unit 115.

Further, in the display control system 100 according to the first embodiment, the ratio of the length L and the height d of one side of the bottom surface of the unit shape 141 is designed so as to satisfy the expression (3). The infrared light 113 can be reflected outside the illumination unit 111 while limiting the reflection angle so that incident light is not totally reflected at the exit surface. By reflecting the infrared light 113 outside the illumination unit 111, the imaging unit 115 can capture the infrared light 113. Moreover, the light emitted from the illumination unit 111 can be efficiently delivered to the imaging unit 115 by designing the reflection sheet 104 so as to satisfy Expression (4).

Therefore, the reading performance of the digital pen 110 is greatly improved.

(Embodiment 2)
The second embodiment will be described with reference to FIGS. Note that differences from the first embodiment will be mainly described, and description of similar points may be omitted.

[1. Constitution]
FIG. 7 is a cross-sectional view illustrating a configuration of a reflective sheet 204 having substantially retroreflective properties according to the second embodiment.

The overall configuration of the display control system in the second embodiment is the same as that in the first embodiment. In the second embodiment, each surface of the unit shape 141 formed on the base layer 143 is curved with a radius of curvature R [mm].

8 is similar to FIG. 7 in that each surface of the unit shape 141 is curved with a radius of curvature R. However, FIG. 8 is different from FIG. 7 in that the uneven surface is arranged to be reversed with respect to the surface of the display device 120.

[2. function]
The optical operation in the display control system using the reflection sheet 204 configured as described above is basically the same as that of the first embodiment. In the second embodiment, the infrared light 113 that has reached the reflection sheet 204 is converted into a desired infrared light 113 that is incident in accordance with the length L of one side of the bottom surface of the unit shape 141 and the radius of curvature R. Diffuse reflection can be performed within an angular range.

Specifically, in the second embodiment, the length L and the curvature are satisfied so as to satisfy the following expression (5) in addition to the expressions (1) and (2) or the expressions (3) and (4). It is desirable to set the radius R.

sin ⁻¹ ((n1 / n2) sin θc) <6 × 28.8 L / R <sin ⁻¹ (n1 / n2) (5)

By changing the radius of curvature R according to the length L of one side of the bottom surface of the unit shape 141, the incident infrared light 113 can be diffused within a desired angular range. Further, by setting the length L and the curvature radius R of the unit shape 141 so as to satisfy the expression (5), the reflection angle of the imaging unit 115 is limited while limiting the reflection angle so as not to be totally reflected on the exit surface of the reflection sheet 204. It can be diffused wider than the angle of view. By diffusing wider than the angle of view of the imaging unit 115, the brightness of the image obtained by the imaging unit 115 becomes more uniform, and reading performance is improved.

In the second embodiment, the imaging unit can capture infrared light more efficiently by satisfying the following expression (6).

(−tan ⁻¹ (Sl / 2hl)) − (θc−tan ⁻¹ ((hc / hl) tan θc)) <sin ⁻¹ ((n2 / n1) sin (6 × 28.8 L / R)) <( tan ⁻¹ (Sl / 2hl) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (6)

Depending on the positional relationship between the imaging unit 115 and the illuminating unit 111, the imaging unit 115 captures most of the infrared light 113 emitted from the illuminating unit 111 by configuring the reflective sheet 204 so as to satisfy Expression (6). It can be reflected within the capture range. Therefore, the utilization factor of light is improved, light that is wasted is reduced, and power consumption in the illumination unit 111 can be reduced.

[3. effect]
In the display control system 100 according to the second embodiment, by designing the angle θt, the length L, and the radius of curvature R to be within the range of the formula (5), the red light incident on the reflection sheet 204 from the illumination unit 111 While reflecting the external light 113 in the direction of the imaging unit 115, it is possible to diffuse within a certain range around the reflected angle. Therefore, an image with uniform brightness can be obtained while obtaining a large amount of light, so that the reading performance of the digital pen 110 is greatly improved.

In all the unit shapes 141 included in the reflection sheet 204, the length L and the radius of curvature R do not have to satisfy the expressions (5) and (6). Usually, 50% or more of the unit shapes 141 among all the unit shapes 141 included in the reflection sheet 204 only need to satisfy the expressions (5) and (6). Even in this case, the effects described above can be obtained.

(Embodiment 3)
Hereinafter, Embodiment 3 will be described with reference to FIG. Note that differences from the first embodiment will be mainly described, and description of similar points may be omitted.

[1. Constitution]
FIG. 9 is a cross-sectional view illustrating a configuration of the reflection sheet 304 according to the third embodiment. In FIG. 9, a part of the reflection sheet 304 (circle C1 portion in FIG. 9) is enlarged, and the surface shape of one of the three surfaces forming the unit shape 141 is schematically shown.

The overall configuration of the third embodiment is the same as that of the first embodiment. The third embodiment is different from the first embodiment in that each surface of the unit shape 141 formed on the base layer 143 is a rough surface.

Here, an angle that is an acute angle formed between a virtual reference surface 341a of the rough surface 141a of the unit shape 141 and a concavo-convex curved surface included in the rough surface 141a is defined as φ [degree]. However, the angle φ is an angle from the reference surface 341a to the tangent in the reflection direction of the rough surface 141a. The virtual reference surface 341a is an approximate surface obtained by the least square method of the depth of the unevenness of the rough surface 141a.

[2. function]
The optical operation of the display control system 100 using the reflection sheet 304 configured as described above is basically the same as that of the first embodiment. In the reflective sheet 304 in Embodiment 3, the infrared light 113 that has reached the reflective sheet 304 can be diffused within an arbitrary angular range centering on the angle of the reflected light, depending on the unevenness angle φ of the rough surface 141a. it can. Specifically, in the third embodiment, the unit shape 141 is designed to satisfy the following expression (7) in addition to the expressions (1) and (2) or the expressions (3) and (4). It is desirable.

sin ⁻¹ ((n1 / n2) sin θc) <6φ <sin ⁻¹ (n1 / n2) (7)
φ: An angle [degree] that is an acute angle formed by a virtual reference surface of the rough surface and a tangent line of the uneven curved surface included in the rough surface

By setting the angle φ so as to satisfy Expression (7), the infrared light 113 incident on the reflection sheet 304 can be diffused within a desired angle range.

Further, by configuring the angle φ to satisfy the above formula (7), the reflection angle is limited so as not to be totally reflected on the exit surface of the reflection sheet 304, and the angle φ is diffused wider than the angle of view of the imaging unit 115. Is possible. By diffusing reflected light toward the digital pen 110 wider than the angle of view of the imaging unit 115, the brightness of the image obtained by the imaging unit 115 becomes more uniform, and reading performance is greatly improved.

In Embodiment 3, the imaging unit 115 can capture reflected light more efficiently by designing the unit shape 141 so as to satisfy the following formula (8).

−tan ⁻¹ (Sl / 2hl) − (θc−tan ⁻¹ ((hc / hl) tan θc)) <sin ⁻¹ ((n2 / n1) sin (6φ)) <tan ⁻¹ (Sl / 2hl) + (Θc-tan ⁻¹ ((hc / hl) tan θc)) (8)

By configuring the reflection sheet 304 in accordance with the positional relationship between the imaging unit 115 and the illumination unit 111 so as to satisfy Expression (8), most of the infrared light 113 is reflected within the range of the angle of view of the imaging unit 115. be able to. Therefore, the light utilization rate is improved, less light is used, and power consumption in the illumination unit 111 can be reduced.

[3. effect]
In the display control system 100 according to the third embodiment, the angle θt and the angle φ are designed to satisfy the expression (7), so that the infrared light 113 incident on the reflection sheet 304 is reflected in the direction of the imaging unit 115. be able to. Further, it can be diffused within a certain range around the reflection angle. Therefore, since the imaging unit 115 can obtain an image with uniform brightness while obtaining a large amount of light, the reading performance of the digital pen 110 is greatly improved.

In addition, in all the unit shapes 141 included in the reflection sheet 304, the angle φ may not satisfy the above formulas (7) and (8). Of all the unit shapes 141 included in the reflection sheet 304, 50% may satisfy the above formulas (7) and (8). Even in this case, the above effect can be sufficiently obtained.

(Embodiment 4)
A display control system according to the fourth embodiment will be described with reference to FIG. Note that only the shape of the reflection sheet is different from the first embodiment. Hereinafter, the configuration different from that of the first embodiment will be mainly described, and the configuration other than that is the same as that of the first embodiment, and thus the description thereof may be omitted.

[1. Constitution]
FIG. 10 is a cross-sectional view illustrating a configuration of the reflection sheet 404 according to the fourth embodiment. In FIG. 10, a part of the reflection sheet 404 (circle C2 portion in FIG. 10) is enlarged, and the surface shape of one of the three surfaces forming the unit shape 141 is schematically shown.

In Embodiment 4, each surface constituting the unit shape 141 on the base layer 143 is curved with a radius of curvature R [mm], and the surface thereof is a rough surface 141b. Here, an acute angle formed by the virtual reference surface 441a having a curved rough surface and the tangent line of the unevenness of the rough surface 141b is defined as φ [degree]. Here, the virtual reference surface 441a is a tangent of a curved surface having a radius of curvature R at the point of obtaining an angle φ of the tangent of the uneven surface of the rough surface 141b.

[2. function]
In the reflection sheet 404 configured as described above, incident light is diffused within a desired angle range according to the length L and the radius of curvature R of the unit shape 141 and the angle φ of the tangent line of the rough surface 141b. Can be reflected. In the fourth embodiment, it is preferable to satisfy the following expression (9) in addition to the expressions (1) and (2) or the expressions (3) and (4).

sin ⁻¹ ((n1 / n2) sin θc) <6 ((28.8L / R) + φ) <sin ⁻¹ (n1 / n2) (9)

Expression (9) changes the magnitude of the radius of curvature R according to the length L of the unit shape 141 and also diffuses and reflects the incident infrared light 113 within an arbitrary angle range by changing the angle φ. Means you can. Furthermore, by configuring the reflection sheet 404 so that the length L, the radius of curvature R, and the angle φ satisfy Expression (9), the reflection angle can be limited to the extent that the reflection surface 404 does not totally reflect. Further, it can be diffused wider than the angle of view of the imaging unit 115. By diffusing wider than the angle of view of the imaging unit 115, the brightness of the image obtained by the imaging unit 115 becomes uniform, and the reading performance is greatly improved.

Further, by designing the reflection sheet 404 so as to satisfy the following expression (10), the imaging unit 115 of the digital pen 110 can capture the infrared light 113 more efficiently.

−tan ⁻¹ (Sl / 2hl) − (θc−tan ⁻¹ ((hc / hl) tan θc)) <sin ⁻¹ ((n2 / n1) sin (6 ((28.8L / R) + φ))) <Tan ⁻¹ (Sl / 2hl) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (10)

A range in which the imaging unit 115 can capture most of the infrared light 113 by configuring the reflection sheet 404 to satisfy Expression (10) according to the positional relationship between the imaging unit 115 and the illumination unit 111 of the digital pen 110. It can be diffusely reflected inside. Therefore, useless light is reduced and power consumption in the illumination unit 111 can be reduced.

[3. effect]
According to the display control system using the reflective sheet 404 disclosed in the fourth embodiment, an image with a more uniform brightness can be obtained by the imaging unit 115. That is, by appropriately selecting the length L, the curvature radius R, and the angle φ of the unit shape 141, the reflection angle can be diffused within an arbitrary angle range, and an image with a more uniform brightness can be obtained by the imaging unit 115. . Therefore, the performance of the digital pen 110 is greatly improved.

Further, by appropriately selecting the angle θt, the length L of the unit shape 141, the curvature radius R, and the angle φ, the infrared light 113 incident on the reflection sheet 404 is reflected at an arbitrary angle, It is possible to diffuse within an arbitrary angle around the angle. Therefore, an image with uniform brightness can be obtained while obtaining a large amount of light, so that the performance of the digital pen 110 is greatly improved.

In addition, in all the unit shapes 141 included in the reflection sheet 404, the length L, the radius of curvature R, and the angle φ may not satisfy the expressions (9) and (10). Usually, 50% of all unit shapes 141 included in the reflection sheet 404 only need to satisfy the expressions (9) and (10). Even in this case, the above effect can be sufficiently obtained.

(Embodiment 5)
Hereinafter, the display control system according to Embodiment 5 will be described with reference to FIGS. 11A, 11B, 12A, and 12B. In addition, since it demonstrates centering around a different structure from Embodiment 1, since it takes the structure similar to Embodiment 1 other than that, description may be abbreviate | omitted.

[1. Constitution]
The display control system according to the fifth embodiment is different from the display control system according to the first embodiment in that the position information pattern sheet 130 is not used.

11A and 12A are enlarged views of the surface of the reflection sheet 504 according to Embodiment 5. FIG.

In Embodiment 5, the reflection sheet 504 has a region where the unit shape 141 exists and a region where the unit shape 141 does not exist. A single unit shape 141 may be present, or a plurality of unit shapes 141 may be arranged close to each other. That is, the arrangement positions of the unit shapes 141 according to the fifth embodiment are arranged at the same interval and density as the marks 131 on the position information pattern sheet 130.

FIGS. 11B) and 12B) are bb cross-sectional views of the reflective sheet 504 shown in FIGS. 11A and 12A.

[2. function]
In the reflection sheet 504 configured as described above, the incident infrared light 113 is reflected toward the imaging unit 115 and is not reflected toward the imaging unit 115 in the region where the unit shape 141 exists and the region where the unit shape 141 does not exist. The area can be divided.

That is, when the infrared light 113 is incident on the region where the unit shape 141 exists, the infrared light 113 can be captured by the imaging unit 115 of the digital pen 110 by being reflected by the inner surface of the unit shape 141.

When the infrared light 113 is incident on a region where the unit shape 141 does not exist, the incident infrared light 113 is not reflected toward the imaging unit 115 from the reflection sheet 504.

Therefore, in the imaging unit 115 of the digital pen 110, the place where the unit shape 141 exists appears bright, and the place where it does not exist appears dark. That is, light and dark can be expressed in an image acquired by the digital pen 110 with or without the unit shape 141. That is, the function equivalent to the mark 131 can be exhibited by the presence or absence of the unit shape 141.

11A and 11B, the region R1 where the unit shape 141 exists is a bright spot. A predetermined pattern such as the mark 131 can be expressed using the bright spots.

On the other hand, in the configuration of FIGS. 12A and 12B, the region R2 where the unit shape 141 does not exist is a dark spot. A predetermined pattern can be expressed like the mark 131 using this dark spot.

Since the mark 131 can be expressed by the unit shape 141 of the reflection sheet 504, the position information pattern sheet 130 may not be provided separately.

Also, the manufacturing cost of the reflection sheet 504 is reduced. The reflection sheet 504 in the fifth embodiment has a smaller number of unit shapes 141 than that in the first embodiment. When the reflection sheet 504 is created from a mold replica, as the number of unit shapes 141 increases, it takes time to process the mold. That is, in the fifth embodiment, since the number of unit shapes 141 is small, the processing time of the mold is short. As a result, the mold can be easily created and the cost is reduced.

Also, by changing the area where the unit shape 141 is present relative to the area of the reflection sheet 504, the total amount of infrared light 113 reflected to the digital pen 110 can be adjusted.

[3. effect]
As described above, by arranging the unit shapes 141, the reflective sheet 504 can have the same function as the position information pattern sheet 130. Therefore, since the position information pattern sheet 130 is not used in the display control system, the number of parts can be reduced and the manufacturing cost can be reduced. Further, since there is a portion where the unit shape 141 is not formed, the number of unit shapes 141 can be reduced, and the manufacturing cost of the mold is reduced.

(Embodiment 6)
Hereinafter, the display control system according to the sixth embodiment will be described with reference to FIGS. 13A and 13B.

[1. Constitution]
The display control system of the sixth embodiment is different from the display control system of the first embodiment in that the position information pattern sheet 130 is not used.

FIG. 13A is an enlarged view showing the surface shape of the reflection sheet 604 in the sixth embodiment. 13B is a cross-sectional view taken along the line bb in FIG. 13A.

The reflection sheet 604 in the sixth embodiment has a region where the infrared light reflection film 144 exists and a region where the infrared light reflection film 144 does not exist on the unit shape 141. That is, the arrangement positions of the infrared light reflection films 144 in the reflection sheet 604 of the sixth embodiment are arranged at the same intervals as the marks 131 in the position information pattern sheet 130.

The infrared light reflection film 144 may be formed along the unit shape 141 when viewed from the top surface, or may be formed in an arbitrary region.

In Embodiment 6, the unit shapes 141 do not have to be spread without gaps. For example, the presence or absence of the unit shape 141 does not matter at a place where the infrared light reflection film 144 is not present. That is, the unit shape 141 may be formed at least at the position where the infrared light reflection film 144 is formed.

At this time, it is desirable that the base layer 143 and the cover layer 142 have the same refractive index.

[2. function]
The reflection sheet 604 configured as described above can be divided into a region that reflects the incident infrared light 113 and a region that does not reflect depending on the presence or absence of the infrared light reflection film 144.

When the infrared light 113 is incident on a region where the infrared light reflection film 144 exists, the infrared light reflection film 144 reflects the infrared light 113 toward the imaging unit 115. The imaging unit 115 of the digital pen 110 can capture the reflected infrared light 113.

When the infrared light 113 is incident on a region where the infrared light reflection film 144 is not present, the incident infrared light 113 is not reflected by the unit shape 141, passes through the reflection sheet 604, and enters the display unit 121. The infrared light 113 reaching the display unit 121 is diffusely reflected by the display unit 121. At this time, the amount of light returning to the imaging unit 115 of the digital pen 110 is so small that the reading operation of the digital pen 110 is not affected.

Therefore, in the imaging unit 115 of the digital pen 110, the area where the infrared light reflection film 144 exists appears bright, and the area where it does not exist appears dark. That is, light and dark can be expressed in an image acquired by the digital pen 110 with or without the infrared light reflection film 144. That is, the function equivalent to that of the mark 131 can be achieved with or without the infrared light reflection film 144.

13A and 13B, the region R3 where the infrared light reflection film 144 exists is captured by the imaging unit 115 of the digital pen 110 as a bright spot. A predetermined pattern such as the mark 131 can be expressed using the bright spots. On the other hand, it is also possible to express the mark 131 in a region where the infrared light reflection film 144 does not exist. 13A and 13B, the region where the infrared light reflection film 144 is provided is the mark 131. However, the present invention is not limited to this. In this case, the region where the infrared light reflection film 144 is missing is captured by the imaging unit 115 as a dark spot. A predetermined pattern can be expressed like the mark 131 using this dark spot.

Since the mark 131 can be expressed by the presence or absence of the infrared light reflection film 144, it is not necessary to provide the position information pattern sheet 130 separately. When the position information pattern sheet 130 is not provided, the number of parts of the entire display control system 100 is reduced, and the cost is reduced.

Also, the manufacturing cost of the reflection sheet 604 is reduced. In the sixth embodiment, the area of the infrared light reflection film 144 is smaller than that in the first embodiment. The smaller the area of the infrared light reflection film 144, the smaller the required material.

In addition, the cost is lowered when it is desired to create various position information pattern sheets 130. In the sixth embodiment, it is possible to cope with various information patterns by changing the arrangement of the infrared light reflection film 144. When the infrared light reflection film 144 is formed by vapor deposition or sputtering of a metal film or a dielectric multilayer film, it is only necessary to change the mask pattern. When the infrared light reflection film 144 is made of a material containing cholesteric liquid crystal or metal fine particles, a pattern may be drawn after making the shape suitable for an inkjet process. Moreover, it can produce similarly by the method of apply | coating from on the mask of a desired pattern.

Thus, the molds for creating the base layer 143 are common, and various position information pattern sheets 130 can be created. Therefore, there is no need to mold each time. Therefore, the manufacturing cost is reduced.

Further, by changing the ratio of the area where the infrared light reflection film 144 is present to the area of the reflection sheet 604, the total amount of the infrared light 113 reflected to the digital pen 110 can be adjusted.

[3. effect]
As described above, by arranging the infrared light reflection film 144 on the unit shape 141, the reflection sheet 604 can have the same function as the position information pattern sheet 130. Therefore, the number of parts of the display device 120 is reduced and the manufacturing cost is reduced. Further, since the area of the infrared light reflection film 144 is reduced, the material for manufacturing can be reduced. In addition, a mold for creating the base layer 143 can be used in common.

(Other embodiments)
As described above, Embodiments 1 to 6 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to embodiments that have been changed, replaced, added, omitted, and the like. Also, it is possible to combine the components described in the first to sixth embodiments to form a new embodiment.

Therefore, other embodiments will be exemplified below.

Embodiments 1 to 6 have been described using a liquid crystal display panel as an example of the display unit 120. The display unit 120 is not limited to a liquid crystal display panel, and may be any device that can display information, such as a flat panel display such as an organic EL (OLED) or a plasma display.

The present disclosure is applicable to a display control system that reads and controls display unit information by a reading device. Specifically, the present disclosure is applicable to electronic devices such as notebook PCs, desktop PCs, and tablet terminals.

DESCRIPTION OF SYMBOLS 100 Display control system 104,204,304,404,504,604 Reflection sheet 110 Digital pen 111 Illumination part 112 Pressure sensor 113 Infrared light 115 Imaging part 115a Imaging lens system 115b Imaging element 116 Pen control part 116a Identification part 116b Microcomputer 117 Transmission unit 120 Display device 121 Display unit 122 Reception unit 123 Microcomputer 130 Position information pattern sheet 131 Mark 132 Base film 133 Cover film 141 Unit shape 142 Cover layer 143 Base layer (reflection layer)
144 Infrared light reflection film 341a, 441a Reference surface

Claims (19)

A display control system,
A reflective layer having a plurality of unit shapes of a substantially triangular pyramid structure combining a display unit and three triangular surfaces; a reflective sheet provided on the display unit; provided on the reflective direction side of the reflective sheet; A display device having a position information pattern indicating position information in the display unit;
An illumination unit and an imaging unit, comprising: a reading device that reads the position information pattern by recognizing the light emitted from the illumination unit and reflected by the reflection sheet by the imaging unit;
The reflection sheet includes a cover layer provided on the reflection direction side of the reflection layer,
A display control system that satisfies the following expression (1).
sin ⁻¹ ((n1 / n2) sin (tan ⁻¹ (Sl / 2hl)) <| 2.25θt-202.5 | <sin ⁻¹ (n1 / n2) (1)
Here, θt: an angle formed by a side formed by contact of two triangular surfaces of the unit shape with another triangular surface n1: a refractive index of a space in which the reader is used n2: a refractive index of the cover layer Sl: Diameter of light irradiation port of the illumination unit hl: distance from the illumination unit to the center of the imaging range of the imaging unit on the reflection sheet. The display control system according to claim 1, wherein the following expression (2) is satisfied.
(Θl−tan ⁻¹ (Sl / 2hl)) − (θc−tan ⁻¹ ((hc / hl) tan θc)) ≦ sin ⁻¹ ((n2 / n1) sin | 2.25θt−202.5 |) ≦ (Θl + tan ⁻¹ (Sl / 2hl)) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (2)
here,
hc: distance from the center of the imaging range to the imaging unit θl: angle formed by the optical axis of the illumination unit and the optical axis of the imaging unit θc: a half angle of view of the imaging unit. The display control system according to claim 2, wherein the reflective layer reflects only light in a specific wavelength band. The display control system according to claim 3, wherein the reflective layer is an infrared reflective layer that transmits visible light and reflects infrared light. The display control system according to claim 2, wherein at least a part of the three surfaces of the unit shape is a curved surface and satisfies the following expression (5).
sin ⁻¹ ((n1 / n2) sin θc) <6 × 28.8 L / R <sin ⁻¹ (n1 / n2) (5)
here,
R: radius of curvature of the curved surface L: length of one side of the bottom surface of the unit shape. The display control system according to claim 2, wherein at least part of the unit-shaped surfaces has three surfaces that are curved surfaces, and satisfies the following expression (6).
-Tan ^-1 (Sl / 2hl)-(θc-tan ^-1 ((hc / hl) tan θc)) <sin ^-1 ((n2 / n1) sin (6 × 28.8L / R)) <tan ^-1 (Sl / 2hl) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (6) The display control system according to claim 2, wherein at least a part of the unit-shaped surface is a rough surface. The display control system according to claim 7, wherein the rough surface satisfies the following expression (7).
sin ⁻¹ ((n1 / n2) sin θc) <6φ <sin ⁻¹ (n1 / n2) (7)
here,
φ: an acute angle formed by a virtual reference surface of the rough surface and a tangent line of the uneven curved surface included in the rough surface. The display control system according to claim 8, wherein the rough surface satisfies the following expression (8).
−tan ⁻¹ (Sl / 2hl) − (θc−tan ⁻¹ ((hc / hl) tan θc)) <sin ⁻¹ ((n2 / n1) sin (6φ)) <tan ⁻¹ (Sl / 2hl) + (Θc-tan ⁻¹ ((hc / hl) tan θc)) (8) The display control system according to claim 7, wherein at least a part of the unit-shaped surface is a curved surface and a rough surface, and satisfies the following expression (9).
sin ⁻¹ ((n1 / n2) sin θc) <6 ((28.8L / R) + φ) <sin ⁻¹ (n1 / n2) (9) The display control system according to claim 2, wherein at least a part of the unit-shaped surface is a curved surface and a rough surface, and satisfies the following expression (10).
−tan ⁻¹ (Sl / 2hl) − (θc−tan ⁻¹ ((hc / hl) tan θc)) <sin ⁻¹ ((n2 / n1) sin (6 ((28.8L / R) + φ))) <Tan ⁻¹ (Sl / 2hl) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (10) The display control system according to any one of claims 1 to 11, wherein the position information pattern is formed in a geometric shape. The display control system according to claim 12, wherein the position information pattern is formed of a material that absorbs light of a specific wavelength. The display control system according to any one of claims 1 to 11, wherein the position information pattern is formed by an array of the unit shapes. The display control system according to any one of claims 1 to 11, wherein the position information pattern is formed by a lack of the unit shape. The display control system according to claim 3 or 4, wherein the position information pattern is realized by the presence or absence of a reflective film for reflecting the specific wavelength. The display control system according to any one of claims 1 to 16, wherein the following expression (a) is satisfied.
Mp <Mc / (2 × Px) (a)
here,
Mp: area when the unit shape is viewed in plane Mc: area of the imaging range on the display unit of the imaging unit Px: number of effective pixels of the imaging unit. A display control system,
A reflective layer having a plurality of unit shapes of a substantially triangular pyramid structure combining a display unit and three triangular surfaces; a reflective sheet provided on the display unit; provided on the reflective direction side of the reflective sheet; A display device having a position information pattern indicating position information in the display unit;
An illumination unit and an imaging unit, comprising: a reading device that reads the position information pattern by recognizing the light emitted from the illumination unit and reflected by the reflection sheet by the imaging unit;
The reflection sheet includes a base layer that forms the unit shape, and a cover layer that is provided on the reflection direction side of the base layer,
A display control system that satisfies the following expression (3).
sin ⁻¹ ((n1 / n2) sin (tan ⁻¹ (Sl / 2hl)) <| 62.65a ² −251.86a + 189.28 | <sin ⁻¹ (n1 / n2) (3)
here,
n1: Refractive index of the space in which the reader is used n2: Refractive index of the cover layer Sl: Diameter of the light irradiation port of the illumination unit hl: From the illumination unit to the imaging range of the imaging unit on the reflective sheet Distance to the center a: The ratio of the length L to the height d of one side of the bottom surface of the unit shape. The display control system according to claim 18, wherein the following expression (4) is satisfied.
(Θl−tan ⁻¹ (Sl / 2hl)) − (θc−tan ⁻¹ ((hc / hl) tan θc)) ≦ sin ⁻¹ ((n2 / n1) sin | 62.65a ² −251.86a + 189.28 |) ≦ (θl + tan ⁻¹ (Sl / 2hl)) + (θc−tan ⁻¹ ((hc / hl) tan θc)) (4)
here,
hc: distance from the center of the imaging range to the imaging unit θl: angle formed by the optical axis of the illumination unit and the optical axis of the imaging unit θc: a half angle of view of the imaging unit.

Images