JP2002311419A - Transparent substrate of liquid crystal display panel, liquid crystal display panel and stereoscopic video display device - Google Patents

Abstract

(57) [Problem] To improve an aperture ratio substantially without reducing a ratio of a non-responsive region in a liquid crystal layer. A liquid crystal display panel according to the present invention includes a transparent array substrate, a transparent substrate opposed to the array substrate, and a liquid crystal layer interposed between the transparent substrate and the array substrate. And The transparent substrate 1 has a flat surface 1a opposed to the pixel region and an inclined surface 1b inclined with respect to the flat surface 1a.
Are formed so as to surround the flat surface 1a. In addition, a reflecting portion 1c is formed on the inclined surface 1b by depositing silver, aluminum, or the like, and a mirror surface is formed on the inclined surface 1b by the reflecting portion 1c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel for displaying an image in response to a liquid crystal, a transparent substrate provided on the liquid crystal display panel, and a stereoscopic image display device including the liquid crystal display panel.

[0002]

2. Description of the Related Art In general, a liquid crystal display device includes an array substrate, a counter substrate facing the array substrate, a liquid crystal layer sandwiched between the array substrate and the counter substrate, and the like. On the surface of the array substrate facing the counter substrate, a plurality of scanning lines arranged in parallel, a plurality of signal lines arranged orthogonal to these scanning lines, a scanning line and a signal line And a switching element disposed at a location where the scanning line intersects with the signal line or near a location where the scanning line and the signal line intersect. The pixel electrode and the switching element are electrically connected. Further, a common electrode is provided on a surface of the counter substrate facing the array substrate. In a color liquid crystal display device, for example, a color filter is interposed between an opposing substrate and a common electrode in addition to the above configurations.

[0003] In such a liquid crystal display device, display is generally performed by applying a voltage to the liquid crystal layer by the pixel electrode and the common electrode. That is, the plurality of pixel electrodes are arranged in a matrix on the array substrate, and the liquid crystal composition between the pixel electrode and the common electrode responds by application. On the other hand, a liquid crystal composition between an insulating region (where the pixel electrode is not arranged on the array substrate) and the common electrode (or the counter substrate), and a liquid crystal composition between the scanning line and the common electrode An object, a liquid crystal composition between the signal line and the common electrode, and a liquid crystal composition between the switching element and the common electrode do not always respond. As described above, when the liquid crystal layer is viewed in a plan view, a response region to which the liquid crystal responds and a non-response region other than the response region exist in the liquid crystal layer. Note that a scan line, a signal line, and a switching element may malfunction when irradiated with light, or in order to improve display contrast ratio characteristics, a light-shielding layer facing the non-response region may be, for example, a counter substrate. In many cases, the light-shielding layer is interposed between the common electrode and the light-shielding layer, which is generally called a black matrix.

[0004]

Incidentally, it is desired that the aperture ratio of the liquid crystal display device be improved. That is, it is desired that the ratio of the scanning line, the signal line, the switching element, or the insulating region on the array substrate is reduced, and the ratio of the non-responsive region in the liquid crystal layer is reduced. However, the scanning lines, the signal lines, the switching elements, and the insulating regions are components necessary for the liquid crystal display device, and there is a limit in reducing the proportion of these components.

Accordingly, an object of the present invention is to substantially improve the aperture ratio without reducing the ratio of the non-responsive region in the liquid crystal layer.

[0006]

According to the first aspect of the present invention,
For example, as shown in FIGS. 1 and 2, in a transparent substrate (1) of a liquid crystal display panel arranged to face a liquid crystal layer (7) having a pixel region that changes in brightness, a flat surface (1 a) facing the pixel region is provided. ) Is provided so as to surround the flat surface, and a mirror surface (reflection portion 1c) is formed on the inclined surface.

According to a second aspect of the present invention, in the transparent substrate of the liquid crystal display panel according to the first aspect, the angle of the inclined surface with respect to the flat surface is larger than 225 degrees.
It is characterized by being smaller than 70 degrees.

According to a fifth aspect of the present invention, there is provided a liquid crystal display panel (1) comprising a liquid crystal layer (7) having a pixel region which changes in brightness and a transparent substrate (1) arranged to face the liquid crystal layer.
In 4), the transparent substrate has a flat surface (1a) facing the pixel region, and an inclined surface (1a) inclined with respect to the flat surface and provided so as to surround the flat surface.
b), wherein a mirror surface (reflection portion 1c) is formed on the inclined surface.

According to a sixth aspect of the present invention, in the liquid crystal display panel according to the fifth aspect, an angle of the inclined surface with respect to the flat surface is larger than 225 degrees and smaller than 270 degrees. In addition, since it is a transparent substrate, light passing through the transparent substrate passes through the flat surface.

According to the first, second, fifth or sixth aspect of the present invention, since the mirror surface is formed on the inclined surface, the light passing through the inside of the transparent substrate (the direction of this light is The direction of the vector is reflected on the inclined surface. Then, since the inclined surface is inclined with respect to the flat surface, light reflected on the inclined surface can enter the flat surface. Here, since the flat surface faces the pixel region, light incident on the flat surface passes to the pixel region. Conversely, when light emitted from the pixel region passes through the flat surface and enters the inclined surface, the light is reflected on the inclined surface. That is, since the observer can see the pixel region on the inclined surface, the region where the pixel region is reflected on the display surface of the liquid crystal display panel is substantially increased. Therefore, the aperture ratio of the liquid crystal display panel is substantially increased without increasing the proportion of the pixel area (even without decreasing the proportion of the non-responsive area (non-pixel area)). Here, since the angle of the flat surface with respect to the inclined surface is larger than 225 degrees and smaller than 270 degrees as in the invention of claim 2, light passing through this transparent substrate in a direction substantially perpendicular to the flat surface is When incident on an inclined surface, the light is almost certainly reflected toward a flat surface. Therefore, the aperture ratio of the liquid crystal display panel is substantially increased.

According to a third aspect of the present invention, in the transparent substrate of the liquid crystal display panel, a mirror surface for reflecting light emitted from a pixel region that changes in brightness is provided at a position corresponding to a non-pixel region other than the pixel region. It is characterized by that.

According to the third aspect of the present invention, a mirror surface is provided at a position corresponding to the non-pixel region, and the mirror surface reflects light emitted from the pixel region, so that the pixel region can be seen on the mirror surface. Therefore, the area where the pixel area is projected on the display surface of the liquid crystal display panel is substantially increased. Therefore, the aperture ratio of the liquid crystal display panel substantially increases without increasing the area of the pixel area.

According to a fourth aspect of the present invention, in the transparent substrate of the liquid crystal display panel according to any one of the first to third aspects, the mirror surface is formed by a given film forming method (for example, silver deposition, aluminum deposition, chromium deposition). (Etching etc.).

The invention according to claim 7 is the invention according to claim 5 or 6.
In the liquid crystal display panel described above, the mirror surface is formed by a given film formation method (for example, silver evaporation, aluminum evaporation, chromium etching, or the like).

According to the fourth or seventh aspect of the present invention, a mirror surface can be easily formed by a film forming method.

According to an eighth aspect of the present invention, there is provided a stereoscopic image display device, wherein the liquid crystal display panel according to any one of the fifth to seventh aspects is provided on a side opposite to the side of the transparent substrate facing the liquid crystal layer. And a lenticular lens disposed opposite to the surface so that a stereoscopic video image can be observed.

According to the eighth aspect of the invention, since the aperture ratio of the liquid crystal display panel is improved, the black band dividing the display area does not appear on the observation screen of the stereoscopic video display device.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the liquid crystal display device according to the present invention will be described with reference to the drawings. However, the drawings are schematically shown to the extent that the invention can be understood, and the scope of the invention is not limited to the illustrated examples.

FIG. 1 is a plan view of a liquid crystal display panel provided in the liquid crystal display device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line AA of FIG. As shown in FIGS. 1 and 2, the liquid crystal display device includes a liquid crystal display panel 14 for displaying an image, a lenticular lens plate 15 disposed opposite to a display surface 14a of the liquid crystal display panel 14, and a display surface 14a.
And a backlight 9 that emits light toward the liquid crystal display panel 14 from the opposite side to the liquid crystal display panel 14. This is a so-called transmission type liquid crystal display device. This liquid crystal display device allows a viewer to observe a stereoscopic image by using a lenticular lens plate 15, and is a so-called stereoscopic image display device.

The lenticular lens plate 15 has a large number of striped microlenses (cylindrical lenses) arranged at intervals substantially corresponding to the pitch of three pixels. In this case, the luminous flux emitted from each pixel reaches the left and right eyes of the observer located in front of the lenticular lens plate 15 by the lens refraction of the lenticular lens plate 15. That is, the luminous flux emitted from the pixel displaying the image information for the left eye reaches only the left eye, and the luminous flux emitted from the pixel displaying the image information for the right eye reaches only the right eye. It should be noted that the left-eye pixel and the right-eye pixel are respectively displayed so as to have a parallax in a case similar to a situation where a person performs stereoscopic perception by binocular parallax, whereby the viewer can view a stereoscopic image. recognize. A large number of microlenses may be arranged at intervals substantially corresponding to the pitch of two pixels or more.

The liquid crystal display panel 14 includes a transparent array substrate 8 and a transparent substrate 1 disposed opposite to the array substrate 8.
And a liquid crystal layer 7 interposed between the transparent substrate 1 and the array substrate 8
And the like.

The array substrate 8 is a transparent substrate made of glass, and is arranged to face the backlight 9. Light emitted from the backlight 9 passes through the array substrate 8.
On the surface of the array substrate 8 on the display surface 14a side, transparent pixel electrodes 10, 10,.
, And conductive signal lines 12, 12,..., And similarly conductive scanning lines 13, 1,.
3,... Are provided.

Are arranged in parallel with each other, and the scanning lines 13, 13,... Are arranged in parallel with each other so as to be orthogonal to the signal lines 12, 12,. The pixel electrodes 10, 10,... Are arranged in a region surrounded by the signal lines 12, 12,... And the scanning lines 13, 13,. Each pixel electrode 10 is electrically connected to the scanning line 13 and is electrically connected to the TFT 11. Each TFT 11 is arranged near the intersection of the signal line 12 and the scanning line 13 and is connected to the signal line 12. , The signal lines 12, 12, ... and the scanning lines 13, 13, ... may be covered with a chromium-based light-shielding film such as chromium or chromium oxide.

, TFTs 11 and 1
, And signal lines 12, 12, ... and scanning lines 13, 13,
Are covered with the alignment film 5b. This alignment film 5b is
The alignment treatment is performed to align the liquid crystal composition of the liquid crystal layer 7.

On the surface of the transparent substrate 1 opposite to the display surface 14a, a color filter 3 colored in three primary colors, a transparent common electrode 6 that transmits light, and an alignment film 5a that has been subjected to alignment processing are sequentially provided. It is laminated. The alignment film 5 a is for aligning the liquid crystal composition of the liquid crystal layer 7. The color filter 3 is colored red, blue, and green, and one color region is arranged to face each pixel electrode 10. Furthermore,
A black matrix 4 is formed on the color filter 3, and the black matrix 4 is connected to the signal lines 12 and 1.
, And the scanning lines 13, 13,. The black matrix 4 may be arranged so as to face the TFTs 11, 11,.... The black matrix 4 blocks out light, and is formed of, for example, chromium, chromium oxide, or the like.

The liquid crystal composition is filled between the alignment films 5a and 5b to form the liquid crystal layer 7.

When a voltage is applied to the liquid crystal layer 7 by the pixel electrode 10 and the common electrode 6, the liquid crystal composition between the pixel electrode 10 and the common electrode 6 responds.
And the liquid crystal composition between the signal line 12, the scanning line 13 and the common electrode 6 does not respond. That is, when the liquid crystal display panel 14 is viewed in a plan view, a region to which the liquid crystal composition responds is a region that becomes a pixel, and is a region that changes in brightness by switching of the TFT 11. On the other hand, a region where the liquid crystal composition does not respond always maintains a dark state even by switching of the TFT 11. In the present specification, when the liquid crystal display panel 14 is viewed in a plan view, a region that changes in brightness by switching of the TFT 11 is referred to as a pixel region, and a region other than the pixel region is referred to as a non-pixel region. In addition, basically, when the liquid crystal display panel 14 is viewed in a plan view, the pixel region is a region corresponding to the pixel electrode 10 (a square region surrounded by two signal lines 12 and two scanning lines 13). . However, when a light-shielding layer such as a black matrix is formed so as to overlap a part of the pixel electrode 10, the region corresponding to the light-shielding layer is also formed by the TFT.
The region corresponding to the light-shielding layer in this case is a non-pixel region because the region is always kept in a dark state regardless of the switching of No. 11.

The transparent substrate 1 arranged to face the liquid crystal layer 7 will be described in detail. The transparent substrate 1 is a transparent substrate made of glass, through which light can pass. The display surface 14a of the transparent substrate 1 is a flat surface. The surface opposite to the display surface 14a is a surface facing the liquid crystal layer 7. The surface facing the liquid crystal layer 7 is a flat surface 1 arranged in an array and parallel to the display surface 14a.
a and an inclined surface 1b inclined with respect to the flat surface 1a. One flat surface 1a is arranged to face one pixel region, and an inclined surface 1b is formed so as to surround the flat surface 1a. A groove 1d having a V-shaped cross section is formed by the inclined surface 1b.
(Or black matrix 4).

The angle θ of the flat surface 1a with respect to the inclined surface 1b is larger than 225 degrees and smaller than 270 degrees, and is preferably as close as 90 degrees as long as the thickness of the transparent substrate 1 is allowed. Further, a reflecting portion 1c for reflecting light is formed in the groove 1d, and the reflecting portion 1c is attached on the inclined surface 1b. The reflecting portion 1c forms a mirror surface on the inclined surface 1b. The reflection portion 1c is formed by vapor deposition of a metal such as aluminum or silver. Further, the reflecting portion 1c may be formed by etching a metal such as chromium. In the case of chromium, the light reflectance is about 60%.

Next, a method of manufacturing the transparent substrate 1 will be described. First, as shown in FIG. 3, both surfaces of a glass substrate 20 are polished so that both surfaces are parallel to each other. Next, as shown in FIG. 4, V-shaped grooves 1d are formed on one surface 20a of the substrate 20 in parallel with each other so as to be at the same interval as the signal lines 12, 12,... (Shaving). At this time, the V-shaped groove 1d
Is substantially the same as the width of the signal line 12, and
The groove 1d is formed so that the depth of the groove 1d is larger than half the width of the groove 1d. Further, V-shaped grooves 1d are formed (cut) on the surface 20a so as to be parallel to each other so as to have the same interval as the intervals of the scanning lines 13, 13, ... arranged on the array substrate 8. At this time, the width of the groove 1d is
The grooves 1d are formed so that the depths thereof are substantially equal to the widths of 3, 13,.

Next, as shown in FIG. 5, aluminum or silver is deposited on the entire surface 20a to form a reflective layer 20b on the entire surface. Next, as shown in FIG. 6, by polishing the surface on which the reflective layer 20b is formed, the reflective layer attached to the flat surface 1a is removed. As described above, the transparent substrate 1 is manufactured.

Next, the operation and effect of the liquid crystal display device of the present embodiment will be described. As shown in FIG.
Light incident on a (the direction of this light is the same as the line-of-sight vector of the observer) is transmitted through the display surface 14a,
Passes through the inside of the transparent substrate. When light passing through the inside of the transparent substrate 1 is incident on the flat surface 1a, the light passes through the flat surface 1a and reaches the color filter 3 corresponding to the pixel region.
In other words, the pixel area is an area that changes between light and dark,
The light emitted from the pixel area reaches the area W1 corresponding to the pixel area on the display surface 14a, and the color of the color filter 3 is projected on the area W1.

On the other hand, light passing through the inside of the transparent substrate 1 (the direction of this light is the same as the line-of-sight vector of the observer).
Is incident on the inclined surface 1b, the reflecting portion 1
Since b is formed, light is reflected on the inclined surface 1b. Then, the light reflected on the inclined surface 1b is reflected on the flat surface 1a.
Incident toward. In other words, the light emitted from the pixel region is reflected by the inclined surface 1b, reaches the region W2 corresponding to a region other than the pixel region (the signal line 12 and the scanning line 13) on the display surface 14a, and also reaches the region W2. Color filter 3
Is projected.

As described above, in the present embodiment, the substantial aperture ratio of the liquid crystal display panel 14 is improved without reducing the ratio of the TFT 11, the signal lines 12, and the scanning lines 13 to the array substrate 8.

Further, since the color of the color filter 3 is projected on almost the entire surface of the display surface 14a, no dark portion is generated between pixels on the display surface 14a. Therefore, the color of each pixel enters the eyes of the observer, so that a dark area in which a display image cannot be observed does not appear on the observation screen, and a black band dividing the display area does not appear on the observation screen. The above points are particularly effective for a stereoscopic image display device including the lenticular lens plate 15. Hereinafter, the reason will be described. If a lenticular lens plate is disposed facing a conventional liquid crystal display panel having a transparent counter substrate,
By each micro lens constituting the lenticular lens plate, not only the pixel region but also the non-pixel region is enlarged. For this reason, not only the enlarged lattice-shaped non-pixel region becomes prominent, but also causes moire fringes and lowers the brightness of the entire stereoscopic image. On the other hand, the n-eye type stereoscopic image display device displays an interleaved image for n eyes as a stereoscopic image and separates the images into n eyes using a lenticular lens plate. For this reason, in order to increase the number of n eyes or to make the image of each individual viewpoint high resolution,
A higher resolution display device capable of displaying a higher resolution stereoscopic image is desired. However, the relationship between the resolution and the aperture ratio is inversely proportional. That is, since the scanning lines and signal lines in the non-pixel area are indispensable parts for each pixel,
This is because there is a limit in increasing the resolution while maintaining a constant aperture ratio. However, the above problem can be solved by the present invention. That is, since the aperture ratio can be substantially increased by the present invention, a display device with higher resolution can be used for a stereoscopic video display device without considering the relationship between resolution and aperture ratio. .

The present invention is not limited to the above-described embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.

In the above embodiment, the groove 1d is formed by shaving the substrate 20, but as shown in FIG. 9, a prism 21 made of a truncated quadrangular pyramid and made of glass is arranged adjacent to the array. A groove 1d as shown in FIG. 8 may be formed. In this case, the transparent substrate 1 is formed by arranging the prisms 21 in an array. Prism 21
Is the inclined surface 1b, the small bottom surface of the prism 21 is the flat surface 1a, and the large bottom surface of the prism 21 is the display surface 14a. Even in this case, the reflecting portion 1 is provided on the inclined surface 1b.
c is adhered, and a mirror surface is formed on the inclined surface 1b. In FIG. 8, the same configuration as the above embodiment is
The same reference numerals are given.

In the above embodiment, the case where the transparent substrate 1 is provided in the transmission type liquid crystal display device has been described. However, the transparent substrate 1 may be provided in the reflection type liquid crystal display device. That is, a reflective layer that reflects light may be provided in place of the backlight 9. Further, although the transparent substrate 1, the substrate 20, and the prism 21 are made of glass, they may be made of a transparent resin such as acrylic.

[0039]

According to the present invention, the light passing through the inside of the transparent substrate can be incident on the flat surface while the light reflected on the inclined surface. Here, since the flat surface faces the pixel region, light incident on the inclined surface passes to the pixel region. Conversely, when light emitted from the pixel region passes through the flat surface and enters the inclined surface, it is reflected on the inclined surface. That is, when the observer sees from a direction substantially perpendicular to the flat surface, the pixel region becomes visible on the inclined surface, so that the region where the pixel region is reflected on the display surface of the liquid crystal display panel substantially increases. .
Therefore, the aperture ratio of the liquid crystal display panel substantially increases without increasing the area of the pixel area.

[Brief description of the drawings]

FIG. 1 is a plan view showing a specific mode of a liquid crystal display panel according to the present invention.

FIG. 2 is a cross-sectional view showing the liquid crystal display panel.

FIG. 3 is a view for explaining a method of manufacturing a transparent substrate included in the liquid crystal display panel, and is a perspective view showing a substrate that is a base of the transparent substrate.

FIG. 4 is a view for explaining a method of manufacturing the transparent substrate, and is a perspective view showing a state where a groove is formed in an original substrate.

FIG. 5 is a view for explaining a method of manufacturing the transparent substrate, and is a perspective view showing a state where a reflection layer is formed on an original substrate.

FIG. 6 is a view for explaining the method of manufacturing the transparent substrate, and is a perspective view showing a state where a part of a reflection layer of an original substrate is removed.

FIG. 7 is a drawing for explaining the operation and effect of the liquid crystal display panel, and is a cross-sectional view showing the liquid crystal display panel.

FIG. 8 is a sectional view showing a liquid crystal display panel of another example different from the liquid crystal display panel.

FIG. 9 is a perspective view showing a prism constituting a liquid crystal display panel of another example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Transparent substrate 1a Flat surface 1b Inclined surface 1c Reflecting part (mirror surface) 7 Liquid crystal layer 10 Pixel electrode 14 Liquid crystal display panel 15 Lenticular lens plate (Lenticular lens) 20 Substrate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) G03B 21/00 G03B 21/00 E 35/00 35/00 A F term (reference) 2H042 AA09 AA15 AA26 DA02 DA03 DA04 DC02 DD01 DE00 2H059 AB06 AB13 2H090 JA03 JB03 JD01 LA13 LA20 2H091 FA14Y FA28X GA01 LA16 LA30

Claims (8)

[Claims] 1. A transparent substrate of a liquid crystal display panel disposed to face a liquid crystal layer having a pixel region that changes in brightness, wherein a slope inclined with respect to a flat surface facing the pixel region surrounds the flat surface. A transparent substrate for a liquid crystal display panel, wherein a mirror surface is formed on the inclined surface. 2. The transparent substrate for a liquid crystal display panel according to claim 1, wherein an angle of said inclined surface with respect to said flat surface is larger than 225 degrees and smaller than 270 degrees. 3. A transparent substrate for a liquid crystal display panel, wherein a mirror surface for reflecting light emitted from a pixel region which changes in brightness is provided at a position corresponding to a non-pixel region other than the pixel region. 4. The transparent substrate of a liquid crystal display panel according to claim 1, wherein said mirror surface is formed by a given film forming method. . 5. A liquid crystal display panel comprising: a liquid crystal layer having a pixel region that changes in brightness; and a transparent substrate disposed to face the liquid crystal layer, wherein the transparent substrate has a flat surface facing the pixel region; A liquid crystal display panel, comprising: a slant surface inclined with respect to the flat surface and provided so as to surround the flat surface, wherein a mirror surface is formed on the slant surface. 6. The liquid crystal display panel according to claim 5, wherein an angle of the inclined surface with respect to the flat surface is larger than 225 degrees and smaller than 270 degrees. 7. The liquid crystal display panel according to claim 5, wherein the mirror surface is formed by a given film forming method. 8. A three-dimensional liquid crystal display comprising: the liquid crystal display panel according to claim 5; and a lenticular lens disposed on a surface of the transparent substrate opposite to a surface facing the liquid crystal layer. A stereoscopic video display device that allows the user to observe visual images.