CN214375665U - Viewing angle control panel and display device - Google Patents

Abstract

The utility model discloses the realization can follow the condition that the incline direction was watched and can't follow the display device who switches between the condition that the incline direction was watched. The utility model provides a centre gripping has visual angle control panel of liquid crystal (250) between first base plate (300) and second base plate (400) separate on the first base plate that first interval is formed with transparent first electrode (11) and edge along the first direction extension parallelly transparent second electrode (12) of first direction extension, first electrode with the second electrode constitutes the electrode pair, the electrode pair is arranged on the second direction the second base plate is formed with edge the light-proof of first direction extension light-proof grid (10) the second base plate covers the light-proof grid ground is formed with transparent common electrode (13), light-proof grid form when overlooking with the electrode pair with the position that the interval between the electrode pair corresponds.

Description

Viewing angle control panel and display device

Technical Field

The present invention relates to a display device that can switch between a case where a picture is viewed from an oblique direction and a case where the picture is not viewed from an oblique direction.

Background

The liquid crystal display device or the organic EL display device can form a flat screen. In addition, since a liquid crystal display device or an organic EL display device can be thin and lightweight, it is applied to various fields. For example, in a mobile device or the like, a configuration in which the viewing is only from the front of the screen and the viewing from an oblique direction is not possible is desired in some cases. On the other hand, in the case where the display device mounted on the automobile cannot be arranged on the front of the driver, a clear image may be required to be seen even in an oblique direction.

Patent document 1 describes the following configuration: two liquid crystal display panels of TN (Twisted Nematic) mode are stacked, one panel is used as a display panel, and the other panel is used as a viewing angle control panel. That is, the liquid crystal display panel of the TN liquid crystal has different directivity of the angle of view depending on the applied voltage. This configuration is used to switch between the case of viewing from the front and the case of viewing from the oblique, thereby controlling the viewing angle by applying a voltage to the viewing angle control panel.

Documents of the prior art

Patent document

Patent document 1: JP 2006-195388 publication

SUMMERY OF THE UTILITY MODEL

Various scenarios are conceivable for a display device capable of viewing angle control. That is, in the case where the image can be visually confirmed only from the front side and cannot be visually confirmed from the oblique direction; in the case where the image can be visually confirmed from an oblique direction but cannot be visually confirmed from the front; and a case where the screen can be visually confirmed from both the front and the oblique directions. In any case, a clear picture is required.

Conventionally, there is no display device that satisfies such a requirement. The utility model discloses a subject can satisfy above display device of this kind of requirement for the realization.

The present invention is to overcome the above-described problems, and particularly, to provide a display device which is configured to use a viewing angle control panel capable of switching between transmission and non-transmission so as to overlap with a display panel when viewing a picture from an oblique direction and when viewing the picture from the front. Specific means are as follows.

(1) A viewing angle control panel in which a liquid crystal is sandwiched between a first substrate and a second substrate, wherein a transparent first electrode extending in a first direction and a transparent second electrode extending in the first direction are formed in parallel with each other at a first interval on the first substrate, the first electrode and the second electrode form an electrode pair, the electrode pair is arranged in a second direction, a light-shielding barrier extending in the first direction is formed on the second substrate, a transparent common electrode is formed on the second substrate so as to cover the light-shielding barrier, and the light-shielding barrier is formed at a position corresponding to the electrode pair and the interval between the electrode pair in a plan view.

(2) The viewing angle control panel according to (1), wherein the second electrode and the first electrode are formed on the second substrate, and the common electrode is formed on the first substrate.

(3) A viewing angle control panel in which a liquid crystal is sandwiched between a first substrate and a second substrate, wherein a transparent common electrode is formed in a planar shape on the first substrate, a first insulating film is formed so as to cover the common electrode, a transparent first electrode extending in a first direction and a transparent second electrode extending in the first direction are formed in parallel with a second gap therebetween on the first insulating film, the first electrode and the second electrode form an electrode pair, the electrode pair is arranged in a second direction, a light-shielding barrier extending in the first direction is formed on the second substrate, and the light-shielding barrier is formed at a position corresponding to the gap between the electrode pair and the electrode pair in a plan view.

(4) The viewing angle control panel according to (3), characterized in that the first electrode and the second electrode are formed on the first substrate, a first insulating film is formed thereon, and a common electrode having a stripe-shaped hole extending in the first direction is formed thereon.

(5) A display device comprising a display panel and a viewing angle control panel, wherein the viewing angle control panel is the viewing angle control panel according to any one of (1) to (4), and the viewing angle control panel is disposed on a front surface of the display panel.

(6) The display device according to (5), wherein the display panel is a liquid crystal display panel.

(7) The display device according to (5), wherein the display panel is an organic EL display panel.

(8) A display device comprising a display panel and a viewing angle control panel, wherein the viewing angle control panel is the viewing angle control panel according to any one of (1) to (4), and the viewing angle control panel is disposed on a rear surface of the display panel.

(9) The display device according to (8), wherein the display panel is a liquid crystal display panel.

Drawings

Fig. 1 is a perspective view showing definition of a field angle with respect to a display panel.

Fig. 2 is a perspective view showing the configuration of embodiment 1.

FIG. 3 is a sectional view of embodiment 1.

Fig. 4 is a plan view of the liquid crystal display panel.

Fig. 5 is a plan view of a pixel in a liquid crystal display panel.

Fig. 6 is a cross-sectional view showing an operation of the IPS mode.

Fig. 7 is a sectional view of the viewing angle control panel.

Fig. 8 is a plan view of fig. 7.

Fig. 9 is a perspective view illustrating an operation of the viewing angle control panel.

Fig. 10 is a plan view of the 1 st substrate of the viewing angle control panel.

Fig. 11 is a plan view showing wiring of the 1 st electrode and the 2 nd electrode of the viewing angle control panel.

Fig. 12 is a plan view of a pixel of the display panel in a case where the display panel and the viewing angle control panel are arranged to overlap.

Fig. 13 is a sectional view of the 2 nd substrate of the viewing angle control panel.

Fig. 14 is a cross-sectional view in the case where the light-shielding grille is formed of two layers.

Fig. 15A is a cross-sectional view of a state in which a light-shielding material is applied to the 2 nd substrate.

Fig. 15B is a cross-sectional view of a state in which a light-shielding gate is patterned.

Fig. 15C is a sectional view of a state where an overcoat film is formed while covering a light-shielding grating.

Fig. 15D is a cross-sectional view showing a state where the second light-shielding grid material is applied on the overcoat film.

Fig. 15E is a cross-sectional view showing a state where the second light-shielding gate is patterned.

Fig. 15F is a sectional view showing a state where an overcoat film is formed covering the second light-shielding gate.

Fig. 16 is a cross-sectional view in the case where the light-shielding grille has a 3-layer structure.

Fig. 17 is a cross-sectional view in a case where the width of the light-shielding grille is increased when the light-shielding grille has a laminated structure.

Fig. 18 is a plan view of a light-shielding grating in the 2 nd substrate of embodiment 2.

Fig. 19 is a sectional view B-B of fig. 18.

FIG. 20 is a plan view showing another example of embodiment 2.

Fig. 21 is a cross-sectional view C-C of fig. 20.

FIG. 22 is a plan view of embodiment 3.

Fig. 23 is a perspective view of embodiment 4.

FIG. 24 is a sectional view of embodiment 4.

Fig. 25 is a perspective view of embodiment 5.

FIG. 26 is a sectional view of embodiment 5.

Fig. 27 is a plan view of the organic EL display panel.

Fig. 28 is a plan view of a pixel of the organic EL display panel.

Fig. 29 is a plan view showing a pixel in a state where an organic EL display panel and a viewing angle control panel are overlapped in embodiment 5.

Fig. 30 is a schematic view of the interior of the automobile.

Fig. 31 is a schematic sectional view showing a problem point of the in-vehicle display device.

Fig. 32 is a sectional view for explaining the problem in example 6.

Fig. 33 is a sectional view of the viewing angle control panel used in fig. 32.

Fig. 34 is a sectional view for explaining another problem in embodiment 6.

Fig. 35 is a sectional view of the viewing angle control panel used in fig. 34.

Fig. 36 is a cross-sectional view of a case where an IPS mode liquid crystal panel is used for the viewing angle control panel.

Fig. 37 is a plan view of fig. 36.

Fig. 38 is a cross-sectional view of another example of the case where the IPS mode liquid crystal panel is used as the viewing angle control panel.

Fig. 39 is a plan view of fig. 38.

The reference numerals are explained below:

10 … light-shielding barrier, 11 … 1 st electrode (for front view), 12 … nd 2 nd electrode (for stereo),

13 … common electrode, 14 … overcoat film, 16 … alignment film, 18 … bus line, 19 … bus line, 20 … light-emitting layer, 21 … protective film, 22 … light-emitting region, 25 … scanning line driver circuit, 26 … video signal line driver circuit, 27 … power supply circuit, 30 … windshield, 31 … automobile dashboard, 32 … steering wheel, 33 … display panel, 34 … display panel, 100 … TFT substrate, 101 … polarizing plate, 111 … scanning line, 112 … video signal line, 113 … pixel, 114 … power supply line, 115 … pixel electrode, 116 … capacitive insulating film, 117 … common electrode, 118 … TFT circuit layer, 120 … display region, 121 … terminal region, 122 … flexible wiring substrate, 131 … common electrode hole, 150 … liquid crystal, 160 …, 171 terminal, sealing material … terminal, 200 … opposing substrate, 201 filter …, … color filter, … filter, …, and color filter, 250 … liquid crystal, 300 … 1 st substrate, 301 … polarizing plate, 400 … nd 2 nd substrate, 401 … polarizing plate, 500 … transparent adhesive material, 600 … organic EL element substrate, 1000 … liquid crystal display panel, 2000 … viewing angle control panel, 3000 … backlight, 4000 … organic EL display panel, 5000 … display device, V1 … 1 st electrode applied voltage, V2 … 1 st electrode applied voltage

Detailed Description

Fig. 1 is a perspective view showing viewing angle characteristics in the display device 5000. In fig. 1, an arrow indicates a direction of light emitted from the display device 5000. In the case of the viewing angle characteristic of the display device 5000, the polar angle direction indicated by θ in fig. 1 and the polar angle direction indicated by θ are used

The azimuth direction indicated. In the present specification, unless otherwise specified, the viewing angle characteristics in the polar angle direction will be described. In addition, in the present invention, the term viewing angle characteristics may be used for the characteristics in the polar angle direction. The present invention will be described in detail below with reference to examples.

[ example 1 ]

Fig. 2 is an exploded perspective view showing the configuration of the display device of the present invention. A viewing angle control panel 2000 using a liquid crystal panel of TN mode is disposed on the back surface of the liquid crystal display panel 1000 of IPS (In Plane Switching) mode, and a backlight 3000 is disposed on the back surface.

In the following embodiments, it is described that the liquid crystal display panel 1000 uses the IPS (in Plane switching) mode liquid crystal display panel 1000, and the viewing angle control panel 2000 uses the TN mode liquid crystal display panel, but the present invention is not limited thereto, and the viewing angle control panel 2000 may use the IPS mode, and the display panel 1000 may also use the TN mode. The IPS mode has excellent viewing angle characteristics, and the TN mode has excellent transmittance characteristics.

Fig. 3 is a sectional view of the structure of fig. 2. In fig. 3, a viewing angle control panel 2000 is disposed above a backlight 3000, and a liquid crystal display panel 1000 is disposed thereon. The viewing angle control panel 2000 and the liquid crystal display panel 1000 are bonded by a transparent adhesive 500.

The viewing angle control panel 2000 is configured such that the liquid crystal 250 is sandwiched between the 1 st substrate 300 on which the first electrode 11 and the 2 nd electrode 12 are formed and the 2 nd substrate 400 on which the common electrode 13 is formed, and the 1 st substrate 300 and the 2 nd substrate 200 are bonded by the sealing material 160. A light-shielding barrier 10 for controlling a viewing angle, which will be described later, is formed on the 2 nd substrate 400. Hereinafter, it is sometimes referred to as the light-shielding gate 10, the layer on which the light-shielding gate 10 is formed, and the light-shielding gate 10 itself. A 1 st polarizing plate 301 is disposed below the 1 st substrate 300, and a 2 nd polarizing plate 401 is disposed above the 2 nd substrate 400.

The liquid crystal display panel 1000 is configured such that a liquid crystal 150 is sandwiched between a TFT substrate 100 on which TFTs (Thin Film transistors) or pixel electrodes are formed and a counter substrate 200 on which color filters are formed, and the TFT substrate 100 and the counter substrate 200 are bonded to each other with a sealing material 160. A 3 rd polarizing plate 101 is disposed under the TFT substrate 100, and a 4 th polarizing plate 201 is disposed on the counter substrate 200.

In fig. 3, the polarization axes of the 2 nd polarizer 401 and the 3 rd polarizer 101 are in the same direction. Therefore, either the 2 nd polarizing plate 401 or the 3 rd polarizing plate 101 can be omitted.

Fig. 4 is a plan view of the liquid crystal display panel 1000. The TFT substrate 100 and the counter substrate 200 are bonded to each other at their peripheries with a sealing material 160, and a liquid crystal is interposed between the TFT substrate 100 and the counter substrate 200. A display region 120 is formed in a portion where the counter substrate 200 and the TFT substrate 100 overlap each other, and a terminal region 121 is formed in a portion where the counter substrate 200 and the TFT substrate 100 do not overlap each other in the TFT substrate 100.

In the display region 120, the scanning lines 111 extend in the lateral direction (x direction) and are arranged in the longitudinal direction (y direction). The video signal lines 112 extend in the longitudinal direction and are arranged in the transverse direction. Pixels 113 are formed in regions surrounded by the scanning lines 111 and the video signal lines 112. A flexible wiring substrate 122 is connected to the terminal region 121 in order to supply signals or power to the liquid crystal display panel.

Fig. 5 is a plan view showing an example of the shape of the pixel electrode 115 in a pixel. In fig. 5, a pixel electrode 115 is formed in a region surrounded by the scanning line 111 and the video signal line 112. In the pixel, a TFT, a via hole, or the like is also formed, but these are omitted in fig. 5.

Fig. 6 is a cross-sectional view of the liquid crystal display panel corresponding to the cross-section a-a in fig. 5. Fig. 6 shows the operation of the IPS liquid crystal display panel, and the detailed configuration is omitted. In fig. 6, a TFT circuit layer 118 is formed on the TFT substrate 100. The TFT circuit layer 118 is a concept including TFTs, signal lines, electrodes, vias, and the like. A common electrode 117 is formed on the TFT circuit layer 118, a capacitor insulating film 116 is formed on the common electrode 117, and a pixel electrode 115 is formed thereon.

In fig. 6, a counter substrate 200 is disposed so as to face the TFT substrate 100 with the liquid crystal 150 interposed therebetween. A color filter 210 is formed on the counter substrate 200. The counter substrate 200 is also provided with a black matrix and an overcoat film, which are omitted in fig. 6. Note that, although alignment films are formed on the surfaces of the TFT substrate 100 and the counter substrate 200 that contact the liquid crystal 150, they are omitted in fig. 6.

In fig. 6, when a voltage is applied to the pixel electrode 115, electric lines of force indicated by arrows in fig. 6 are generated, and the liquid crystal molecules are rotated. Thereby, an image is formed by controlling the transmittance of light in the liquid crystal layer 150.

Fig. 7 is a sectional view of the viewing angle control panel 2000. In fig. 7, a 1 st electrode 11 and a 2 nd electrode 12 are formed in a stripe shape on a 1 st substrate 300. In fig. 7, a 2 nd substrate 400 is disposed with a liquid crystal layer 250 interposed therebetween. A light-shielding layer 10 including a light-shielding louver 10 and an overcoat film 14 made of a transparent resin is formed on the 2 nd substrate 400, and a transparent common electrode 13 is formed on the overcoat film 14. In fig. 7, when a voltage V1 is applied to the 1 st electrode 11 or a voltage V2 is applied to the 2 nd electrode 12, a vertical electric field is generated between the common electrode 13 and the liquid crystal molecules, and the light transmittance of the liquid crystal layer 250 is controlled. Further, since the liquid crystal is electrolyzed when a dc voltage is applied for a long time, it is necessary to apply an ac voltage. Hereinafter, the voltage V1 and the voltage V2 are referred to as the effective voltage value of the ac voltage.

In fig. 7, the 1 st electrode 11 forms an image in a case where it is viewable from the front of the screen, and the 2 nd electrode 12 forms an image in a case where it is viewable from an oblique direction. In the viewing angle control panel 2000, graying out is not required, and thus, V1 or V2 may be some voltage for see-through light or shade light.

Fig. 8 is a plan view of fig. 7, and the strip-shaped 1 st electrode 11 and the strip-shaped 2 nd electrode 12 are formed in parallel with a small spacing d (e.g., 3 μm) therebetween. The 1 st electrode 11 and the 2 nd electrode 12 are formed of a transparent electrode based on, for example, ITO (Indium Tin Oxide). Here, the small interval means a degree of maintaining insulation between the electrodes. In fig. 8, in the case of using the 1 st electrode 11 and the 2 nd electrode 12 as counter electrodes, a light-shielding gate 10 is formed for each pair of electrodes.

Returning to fig. 7, when the voltage V1 applied to the 1 st electrode 12 is turned on when the screen is viewed from the front, light is transmitted through the liquid crystal layer 250 corresponding to the region a. On the other hand, when the voltage V2 applied to the 2 nd electrode 12 is turned on when the screen is viewed from the oblique right direction, light is transmitted through the liquid crystal layer 250 corresponding to the region B. On the contrary, the voltage V2 of the 2 nd electrode 12 is turned off so that the screen cannot be viewed from the oblique direction.

In the configuration of fig. 7, when viewed from the front of the screen, the region corresponding to the 1 st electrode 11 and the region corresponding to the 2 nd electrode 12 are both visually recognizable, and therefore, the difference between the luminance in the front and the luminance in the oblique direction becomes large. If this is a problem, for example, the voltage V1 of the 1 st electrode 11 may be turned off.

In fig. 7, the case of viewing from the oblique right direction with respect to the screen is assumed, but when viewing from the oblique left direction with respect to the screen, the operations of the 1 st electrode 11 and the 2 nd electrode 12 may be reversed. That is, the voltage applied to the 1 st electrode 11 and the voltage applied to the 2 nd electrode 12 may be reversed. In the following description, a case of viewing from an oblique right direction with respect to the screen is assumed, but the same theory may be applied to a case of viewing from an oblique left direction.

Fig. 9 is a perspective view corresponding to the configuration of fig. 7. In fig. 9, the 1 st and 2 nd stripe-shaped electrodes 11 and 12 extend in the y direction and are arranged in the x direction. The common electrode 13 is opposed to the liquid crystal layer 250. On the common electrode 13, a light-shielding gate 10 having a predetermined height extends in the y direction.

The region corresponding to the 1 st electrode 11 cannot be viewed from an angle larger than θ corresponding to the arrow in fig. 9. Only the region corresponding to the 2 nd electrode 12 can be viewed from the direction of θ indicated by an arrow. Therefore, when the 2 nd electrode 12 is turned off, the screen cannot be visually confirmed from an oblique direction.

The degree of the angle θ at which the screen cannot be visually recognized, that is, the viewing angle characteristic, varies depending on the purpose of the display device. The viewing angle characteristic, i.e., θ in fig. 9, can be designed according to the height of the light-shielding barrier 10 and the widths of the 1 st electrode 11 and the 2 nd electrode 12.

Fig. 10 is a plan view of the 1 st electrode 11 and the 2 nd electrode 12 of the viewing angle control panel 2000. In fig. 10, the 1 st and 2 nd stripe-shaped electrodes 11 and 12 extend in the y direction and are arranged in the x direction with a gap d therebetween. The width w of the 1 st and 2 nd electrodes is, for example, 7 micrometers, the gap d is 3 micrometers, and the pitch p is 10 micrometers. In fig. 10, the width w of the 1 st electrode 11 and the 2 nd electrode 12 is the same, but may be changed as necessary.

Fig. 11 is a plan view of the entire 1 st substrate 300. As shown in fig. 11, the 1 st electrode 11 is connected to the terminal 171 through the upper bus line 18, and the 2 nd electrode 12 is connected to the terminal 172 through the lower bus line 19. Therefore, it is not necessary to provide the 1 st substrate 300 with a multilayer wiring, and the structure can be simplified.

Fig. 12 is a plan view showing a relationship between the pixel in the liquid crystal display panel 1000 and the 1 st electrode 11 and the 2 nd electrode 12 of the viewing angle control panel 2000 in a case where the liquid crystal display panel 1000 and the viewing angle control panel 2000 are overlapped. In fig. 12, in the liquid crystal display panel 1000, a pixel electrode 115 is formed in a pixel region surrounded by a scanning line 111 and a video signal line 112. The stripe-shaped 1 st electrode 11 and 2 nd electrode 12 formed on the viewing angle control panel 2000 overlap pixels of the liquid crystal display panel 1000.

As shown in fig. 12, 5 1 st electrodes 11 and 5 2 nd electrodes 12 are present in 1 pixel. That is, when the screen is viewed from an oblique direction with respect to the screen, light passing through a portion corresponding to the 2 nd electrode 12 is used as a backlight in each pixel to form an image.

That is, in the case where the display panel is viewed from an oblique direction, a portion corresponding to the 2 nd electrode 12 is cut out from the pixel and visually confirmed. Therefore, the greater the number of the 2 nd electrodes 12 in the pixel, the more realistically the image is reproduced. Then, the transmittance of the pixel is decreased due to the existence of the interval d between the 1 st electrode 11 and the 2 nd electrode 12 and the existence of the light-shielding gate 10 for each pair of the 1 st electrode 11 and the 2 nd electrode 12. Therefore, the degree to which the pixels are divided by the 1 st electrode 11 and the 2 nd electrode 12 is determined to achieve both of image reproducibility and screen brightness when viewed from an oblique direction.

In this manner, the number of pixels, the 1 st electrode 11, and the 2 nd electrode 12 is determined as needed, but at least one pair of the 1 st electrode 12 and the 2 nd electrode 12 is preferably present in at least 1 pixel. In the case where only 1 st electrode or only 1 nd electrode is present corresponding to 1 pixel, the fineness of the screen may be deteriorated. In addition, it is preferable that the 1 st electrode 11 and the 2 nd electrode 12 are present in the same number in 1 pixel. Therefore, the total number of the 1 st electrode 11 and the 2 nd electrode 12 is preferably an even number of 2 or more for 1 pixel.

Fig. 13 is a sectional view showing the light-shielding barrier 10 formed on the 2 nd substrate 400. Fig. 13 is a top-bottom opposite view to fig. 7. In fig. 13, the width w1 of the light-shielding grid 10 is, for example, 3 micrometers, the pitch p1 is 10 micrometers, and the height h1 is 15 micrometers. The light-shielding barrier 10 can be made of the same material as the black matrix used for the display panel 1000, for example. An overcoat film 14 is formed between the light-shielding barriers 10 and 10. The overcoat film 14 functions as a planarizing film and is formed to be thicker than the height of the light-shielding grating 10, for example, by about t1 (for example, 3 μm). A common electrode 13 is formed on the overcoat film 14, and an alignment film 16 is formed thereon.

In the light-shielding grille 10 shown in fig. 13, since the ratio of the height h1 to the width w1 is high, the manufacturing is difficult. Fig. 14 is a cross-sectional view showing a configuration in which the light-shielding grille 10 is formed by being divided into two layers to facilitate manufacturing. In fig. 14, the light-shielding grill 10 is formed by overlapping two layers of the light-shielding grill 10 having a height h 2. If the height h2 of each light-shielding grill 10 is, for example, 6 micrometers and the thickness t2 of the overcoat film 14 between the light-shielding grills 10 and 10 is 3 micrometers, the height of the entire light-shielding grill 10 is 15 micrometers, which is the same as the light-shielding grill 10 in fig. 13.

Fig. 15A to 15F are cross-sectional views showing steps in forming the light-shielding grille 10 shown in fig. 14. Fig. 15A is a cross-sectional view showing a state where a material to be the lower light-shielding barrier 10 is applied to the 2 nd substrate 400 at a thickness h 2. Fig. 15B is a cross-sectional view showing a state where the lower light-shielding gate 10 is patterned with a height h2 and a width w 1. Fig. 15C is a cross-sectional view showing a state where the overcoat film 14 is formed covering the lower light-shielding grille 10.

Fig. 15D is a cross-sectional view showing a state where the material of the upper light-shielding grid 10 is applied to the outer coating film 14 at a thickness h 2. Fig. 15E is a cross-sectional view showing a state where the upper light-shielding barrier 10 is formed with a width w1 and a height h 2. Fig. 15F is a cross-sectional view showing a state where the upper light-shielding grille 10 is covered with the overcoat film 14. By repeating the steps shown in fig. 15A to 15F, the light-shielding grille 10 having a necessary number of layers of two or more layers can be formed.

Fig. 16 is a cross-sectional view in the case where the light-shielding grille 10 is configured by 3 layers. In fig. 16, the height h2 of the light-shielding grids 10 of each layer is, for example, 3 micrometers, the width w2 of the light-shielding grids 10 is 3 micrometers, and the thickness of the overcoat film 14 between the light-shielding grids 10 and the light-shielding grids 10 in the cross-sectional direction is 3 micrometers. In the configuration of fig. 16, light having an angle smaller than θ 1 and passing through the interval t2 between the lower layer louver 10 and the upper layer louver 10 is emitted to the outside. When light having an angle smaller than θ 1 is to be blocked, measures such as increasing the width w2 of the louver 10 or decreasing the film thickness t2 of the overcoat film 14 on the louver 10 can be taken.

Fig. 17 is a sectional view in a case where the width of the light-shielding grille 10 is increased and w3 is set. In this case, light up to the angle θ 2 can be blocked. Since the display device is set in advance to shield light at a certain angle, the width w3 of the light-shielding bars, the film thickness t2 of the overcoat film, the pitch of the light-shielding bars, that is, the width of the 1 st electrode 11 and the 2 nd electrode 12 formed on the 1 st substrate 300 may be determined.

In the above description, the 1 st electrode 11 and the 2 nd electrode 12 are formed on the first substrate 300, and the common electrode 13 is formed on the second substrate 400. However, the present invention may be configured such that the common electrode 13 is formed on the first substrate 300 and the 1 st electrode 11 and the 2 nd electrode 12 are formed on the second substrate 400, in contrast to this.

[ example 2 ]

In example 1, the viewing angle characteristic in the lateral direction of the tilt of the screen is controlled, but there is a case where the viewing angle characteristic in the upward direction of the tilt of the screen or in the downward direction of the tilt of the screen is desired to be controlled. Fig. 18 is a plan view showing a configuration that can meet such a requirement.

In fig. 18, a lateral barrier 10 is formed so as to cross a 1 st electrode 11 formed on a 1 st substrate 300. The lateral louver 10 controls the emission of light in an obliquely upward direction or an obliquely downward direction with respect to the screen. In fig. 18, the angle θ y means that light at an angle smaller than θ y is blocked.

Fig. 19 is a sectional view B-B of fig. 18. In fig. 19, a 1 st electrode 11 is formed on a 1 st substrate 300. A2 nd substrate 400 is arranged so as to sandwich a liquid crystal 250, a light-shielding grating 10 and an overcoat film 14 are formed on the 2 nd substrate 400, and a common electrode 13 is formed on the overcoat film 14. In fig. 19, light emitted at an angle smaller than θ y is blocked by the light-blocking barrier 10.

In fig. 18, the louver 10 extending in the vertical direction controls light in the diagonally right direction of the screen or in the diagonally left direction of the screen as described in embodiment 1. Therefore, for the backlight passing through the 1 st electrode 11 shown in fig. 18 and 19, light in an obliquely upward direction, an obliquely downward direction, or an obliquely rightward direction, an obliquely leftward direction is restricted.

On the other hand, the portion corresponding to the 2 nd electrode 12 is not affected by the light-shielding grating 10. That is, the light passing through the 2 nd electrode 12 can be visually confirmed in any one of the oblique upward direction, the lateral direction, and the oblique downward direction. Therefore, similarly to the description of embodiment 1, by controlling the voltages applied to the 1 st electrode 11 and the 2 nd electrode 12, the emission of light from the display device in the predetermined viewing angle direction can be controlled. That is, in order to make it impossible to visually confirm the image from the oblique direction, a voltage for turning the liquid crystal layer 250 into the light-shielding state may be applied to the 2 nd electrode 12.

In addition, it may not be desirable to emit light in the vertical direction of the screen. In this case, as shown in fig. 20, the light-shielding barriers 10 facing the side surfaces may be disposed not only in the portions corresponding to the 1 st electrodes 11 but also in the portions corresponding to the 2 nd electrodes 12. Fig. 21 is a cross-sectional view C-C of fig. 20. Fig. 21 is the same as fig. 19 except that the electrode formed on the 1 st substrate 300 is the 2 nd electrode 12. As shown in fig. 21, light passing through the 2 nd electrode 12, which is responsible for emitting light in an oblique direction, passes through the light-shielding grating 10 in the lateral direction and is not emitted in a direction smaller than θ y in fig. 21 in an oblique downward direction and an oblique upward direction. Therefore, light in the obliquely downward direction and the obliquely upward direction can be restricted.

Further, since the light-shielding grating 10 is formed of a black light-shielding film, it has an effect of improving the contrast of a screen, similarly to the black matrix. Therefore, such a configuration shown in fig. 20 can improve the contrast in the case where the screen is viewed from the front.

[ example 3 ]

Embodiment 1 controls the viewing angle characteristics with respect to the oblique direction in the x-axis direction as the lateral direction. In other words, to control the azimuth

The viewing angle characteristic in the direction of 0. On the other hand, it is desirable to address the azimuth

The viewing angle characteristics are controlled for cases other than 0.Fig. 22 is a plan view showing a configuration that can achieve this.

The structure of fig. 22 is different from the structure of fig. 12 in example 1 in that the extending direction of the 1 st electrode 11 and the 2 nd electrode 12 is not the y direction but is shifted from the y direction

That is, at an azimuth angle of

The viewing angle control characteristics explained in embodiment 1 are applied in the direction. At azimuth angle

The contents described in embodiment 1 can be applied as they are, in cases other than 0.

For example, the present invention can be applied to a case where the 1 st electrode 11 and the 2 nd electrode 12 are rotated by 90 degrees and the 1 st electrode 11 and the 2 nd electrode 12 are extended in the x direction. In this case, the viewing angle characteristic in the obliquely upward direction or the obliquely downward direction of the control screen is obtained. As described above, the present invention can set a predetermined viewing angle characteristic in any azimuth direction.

Another feature of fig. 22 is that moire fringes generated between the liquid crystal display panel 1000 and the viewing angle control panel 2000 can be reduced by shifting the extending direction of the 1 st electrode 11 and the 2 nd electrode 12 from the y direction. That is, the 1 st electrode 11 and the 2 nd electrode 12 formed on the 1 st substrate 300 extend in the y direction, which means that the light-shielding barrier 10 formed between the 1 st electrode 11 and the 2 nd electrode 12 also extends in the y direction.

When the light-shielding gate 10 extends in the y direction, interference with the video signal lines 112 formed on the TFT substrate 100 of the liquid crystal display panel 1000, the black matrix formed on the counter substrate 200, or the like occurs, and moire fringes occur. Moire can be significantly improved by simply extending the louver 10 in a direction in which the azimuth angle is rotated by about 5 degrees or more. Therefore, when the viewing angle characteristic in the direction in which the azimuth angle is 0 is to be controlled, moire can be reduced by rotating the extending direction of the 1 st electrode 11, the 2 nd electrode 12, and the louver 10 of the 1 st substrate 300 by about 5 degrees from the y direction, and the image quality can be improved as a whole.

[ example 4 ]

In embodiments 1 to 3, a configuration in which the viewing angle control panel 2000 is disposed on the rear surface of the liquid crystal display panel 1000 is described. However, the present invention is not limited to this configuration, and can be applied to a configuration in which the viewing angle control panel 2000 is disposed on the front surface and the liquid crystal display panel 1000 is disposed on the back surface. Fig. 23 is an exploded perspective view showing the configuration of example 4, in which a liquid crystal display panel 1000 is disposed above a backlight 3000, and a viewing angle control panel 2000 is disposed at the uppermost portion.

Fig. 24 is a sectional view of a liquid crystal display device in embodiment 4. In fig. 24, a liquid crystal display panel 1000 is disposed on a backlight 3000, and a viewing angle control panel 2000 is disposed thereon. Fig. 24 is different from fig. 3 of embodiment 1 only in that the vertical relationship between the liquid crystal display panel 1000 and the viewing angle control panel 2000 is reversed, and the configuration of the liquid crystal display panel 1000 and the configuration of the viewing angle control panel 2000 are the same as those described in embodiment 1. All of the various forms described in embodiment 1 can be applied to the structure of the light-shielding grille 10 in fig. 24.

[ example 5 ]

Examples 1 to 4 describe the case where the present invention is applied to a liquid crystal display device. However, the present invention is not limited to the liquid crystal display device, and can be applied to other flat panel displays such as an organic EL display device. Fig. 25 is an exploded perspective view of an organic EL display device to which the present invention is applied. In fig. 25, a viewing angle control panel 2000 is disposed on an organic EL display panel 4000. The viewing angle control panel 2000 is a liquid crystal panel as described in embodiment 1 and the like.

Fig. 26 is a sectional view of a state where the organic EL display panel 4000 and the viewing angle control panel 2000 are bonded. In fig. 26, a light-emitting layer 20 including an organic EL layer, a switching TFT, a driving TFT, a scanning line, a video signal line, a power supply line, and the like is formed on an element substrate 600. A protective film 21 is formed to cover the light-emitting layer 20. A viewing angle control panel 2000 is attached to the protective film 21 with a transparent adhesive material 500 interposed therebetween. The constitution of the viewing angle control panel 2000 is the same as that explained in fig. 3 of embodiment 1.

Fig. 27 is a plan view of the organic EL display panel 4000. In fig. 27, the scanning line driving circuit 25 is arranged in the lateral direction around the display region 120, the video signal line driving circuit 26 is arranged below the periphery, and the power supply circuit 27 is arranged above the periphery. In fig. 27, the scanning lines 111 extend in the transverse direction (x direction) and are arranged in the longitudinal direction (y direction). The video signal lines 112 and the power lines 114 extend in the longitudinal direction and are arranged in the lateral direction. The pixels 113 are present in a region surrounded by the scanning lines 111 and the video signal lines 112 or a region surrounded by the scanning lines 111 and the power supply lines 114.

Fig. 28 is a plan view of a pixel. In fig. 28, a light emitting region 22 formed by an organic EL layer exists in a pixel surrounded by a scanning line 111 and a video signal line 112. In fig. 28, the TFT, the electrode, the via hole, and the like in the pixel are omitted.

Fig. 29 is a plan view of a pixel in a state where the organic EL display panel 4000 overlaps with the viewing angle control panel 2000. The configuration of fig. 29 is the same as that of fig. 12 in embodiment 1. That is, the 1 st electrode 11 and the 2 nd electrode 12 in the viewing angle control panel 2000 are 5 and 5, respectively, corresponding to the pixel, and the light-shielding barrier 10 is provided for each pair of the 1 st electrode 12 and the 2 nd electrode 12. The configuration and the function of the light-shielding barrier 10 formed on the 2 nd substrate 400 of the viewing angle control panel 2000 are the same as those described in embodiment 1.

[ example 6 ]

The display device according to the present invention is used as a display panel inside a vehicle in many cases. Fig. 30 is a schematic view of the interior of the automobile. In fig. 30, the driver sits in the seat opposite the steering wheel 32. A display 33 that displays various information is disposed in a diagonally downward direction of the driver. A comparatively wide region 31 called an instrument panel is located below the windshield 30. By using this region 31 as the display panel 34, a relatively wide display region can be secured, and thus driving information can be displayed.

However, the driver views the display panel 34 from an oblique direction. Since the display panel 34 is disposed directly below the windshield 30, various problems arise in relation to the windshield.

Fig. 31 is a schematic cross-sectional view showing an example of this problem. In fig. 31, light from the display panel 34 is also emitted toward the windshield 30 and is reflected on the windshield 30. This reflection (region a in fig. 31) may occur as long as an image is displayed on the display panel 34, and may therefore obstruct the field of view of the driver.

Therefore, as shown in fig. 32, if light from the display panel 34 is not emitted in the normal direction of the screen, the screen can be prevented from being reflected on the windshield 30. On the other hand, it is assumed that light directed from the display panel 34 to the eyes of the driver can be secured. Fig. 33 is a sectional view of the viewing angle control panel 2000 for achieving such an effect. The display panel 34 may be a liquid crystal display panel or an organic EL display panel.

The configuration of fig. 33 is basically the same as fig. 7 in embodiment 1, but the configuration of the light-shielding barrier 10 formed on the 2 nd substrate 400 of the viewing angle control panel 2000 is different. In fig. 33, a 1 st electrode 11 and a 2 nd electrode 12 are formed in parallel on a 1 st substrate 300. The 2 nd substrate 400 is disposed so as to sandwich the liquid crystal layer 250. A light-shielding grating 10A for shielding light from the 2 nd electrode 12 in the normal direction of the screen is formed on the 2 nd substrate 400. An overcoat film 14 is formed so as to cover the light-shielding grill 10A, and the light-shielding grill 10 described in example 1 for shielding light in an oblique direction is formed on the overcoat film 14. An overcoat film 14 is formed to cover the light-shielding grating 10 and a common electrode 13 is formed thereon.

In fig. 33, such a voltage V1 that blocks light from the back surface by the liquid crystal layer is applied to the counter electrode 11. Such a voltage V2 that allows light from the back surface to pass through is applied to one electrode 12. Therefore, light in an oblique direction, that is, light in the θ direction shown in fig. 33, which is not blocked by the light-shielding grating 10, passes through. On the other hand, light passing through the 2 nd electrode 12 and traveling in the normal direction of the screen is shielded by the light-shielding grating 10A.

Therefore, the configuration of fig. 33 can pass only light at an angle θ through the screen. If the angle θ is set to the position of the eyes of the driver in fig. 32, the screen of the display panel 34 can be prevented from being reflected on the windshield 30, and the driver can view the image of the display panel 34 as needed without being hindered from the view in the forward direction.

On the other hand, the Display device 34 disposed on the instrument panel 31 may be used as a HUD (Head Up Display). That is, the image of the display panel 34 is projected onto the windshield 30, and information necessary for driving can be recognized without greatly changing the line of sight while driving.

In this case, it is desirable that the image formed on the display panel 34 is mapped only on the HUD and cannot be directly recognized from the display panel 34. Fig. 34 is a schematic sectional view of a HUD using a windshield of an automobile. In fig. 34, the image displayed on the display panel 34 is recognized only from the windshield 30 as the HUD, and cannot be directly visually recognized from the display panel 34.

Fig. 35 is a sectional view of a viewing angle control panel 2000 used in the display device for realizing such a configuration. The sectional configuration of fig. 35 is the same as that of fig. 7 in embodiment 1. However, the configuration of fig. 35 is characterized by the method of applying the voltages of the 1 st electrode 11 and the 2 nd electrode 12 formed on the 1 st substrate 300. In fig. 35, a voltage V2 applied to the 2 nd electrode 12 is applied with such a voltage that light from the back surface is blocked by the liquid crystal layer 250.

On the other hand, the voltage V1 for passing light from the back surface is applied to the 1 st electrode 11. The light passing through the 1 st electrode 11 travels in the normal direction of the screen, and therefore, forms an image on the windshield, and can be used as a HUD. On the other hand, the light in the region corresponding to the electrode 11 cannot be visually recognized from an oblique direction due to the presence of the light-shielding grating 10.

When the display panel is intended to be used as both a HUD and a direct view, the voltage V2 applied to fig. 12 may be a voltage that allows light to pass through the liquid crystal. This is the same way as explained in fig. 7. In addition, when both the voltages applied to the electrodes 11 and 12 are voltages that transmit light, the luminance of the screen used in the HUD can be set to be higher than the luminance for visually confirming the image of the display panel from an oblique direction.

[ example 7 ]

In examples 1 to 6, the viewing angle control panel 2000 used a TN mode liquid crystal panel. Not limited to this, the viewing angle control panel 2000 can also use a liquid crystal panel of the IPS mode. The IPS mode liquid crystal panel is particularly suitable for controlling light emitted in an oblique direction because of its excellent viewing angle characteristics. The operation of the IPS mode is the same as that described in fig. 6.

Fig. 36 is a cross-sectional view of a case where the IPS mode liquid crystal panel is used for the viewing angle control panel 2000. In fig. 36, the configuration of the 2 nd substrate 400 including the light-shielding grating 10 is the same as that described in fig. 7. In the 1 st substrate 300, the common electrode 13 is formed in a planar shape, the capacitor insulating film 116 is formed so as to cover the common electrode 13, and the 1 st electrode 11 and the 2 nd electrode 12 are formed in parallel thereon.

Fig. 37 is a plan view of the 1 st electrode 11, the 2 nd electrode 12, and the light-shielding grating 10 formed on the 1 st substrate 300. Based on the principle of IPS operation, the widths of the 1 st electrode 11 and the 2 nd electrode 12 are smaller than those in fig. 7. However, the roles of the 1 st electrode 11 and the 2 nd electrode 12 as the viewing angle control panel 2000 are the same as those of fig. 7. That is, the on/off control of light passing through each electrode is performed in accordance with the voltage between the 1 st electrode 11 and the common electrode 13 or between the 2 nd electrode 12 and the common electrode 13. The other operations of the viewing angle control panel 2000 are the same as those described in fig. 7 and the like of embodiment 1.

Fig. 38 is a cross-sectional view showing another configuration of the viewing angle control panel 2000 based on the IPS mode. Fig. 38 is different from fig. 36 in that the 1 st electrode 11 and the 2 nd electrode 12 are located below the common electrode 13. A common electrode hole 131 is formed in the common electrode 13, and electric lines of force generated by an electric field between the 1 st electrode 11 or the 2 nd electrode 12 and the common electrode 13 penetrate into the liquid crystal from the hole 131 to rotate liquid crystal molecules and control on/off of light.

Fig. 39 is a plan view of fig. 38. In fig. 39, the 1 st electrode 11 and the 2 nd electrode 12 extend in the y direction with a small interval. The light-shielding barriers 10 extend in the y direction for each pair of electrodes of the 1 st electrode 11 and the 2 nd electrode 12. In addition, the hole 131 formed in the common electrode 13 is extended in the y direction so that the 1 st electrode 11 and the 2 nd electrode 12 overlap.

The 1 st electrode 11 and the 2 nd electrode 12 function in the same manner as in fig. 7 or fig. 36. That is, the on/off control of the light passing through each electrode is performed in accordance with the voltage between the 1 st electrode 11 and the common electrode 13 or between the 2 nd electrode 12 and the common electrode 13. The other operations of the viewing angle control panel 2000 are the same as those described in fig. 7 and the like of embodiment 1.

Claims (20)

1. A viewing angle control panel which sandwiches a liquid crystal between a first substrate and a second substrate, characterized in that,

a transparent first electrode extending in a first direction and a transparent second electrode extending in the first direction are formed in parallel with the first substrate at a first interval therebetween, the first electrode and the second electrode form an electrode pair, and the electrode pair is arranged in a second direction,

a light-shielding grating extending in the first direction is formed on the second substrate,

a transparent common electrode is formed on the second substrate so as to cover the light-shielding gate,

the light-shielding gate is formed at a position corresponding to the electrode pair and a space between the electrode pair in a plan view.

2. The viewing angle control panel of claim 1,

the height of the light-shielding gate is greater than the thickness of the light-shielding gate in the second direction.

3. The viewing angle control panel of claim 1,

a transparent resin is formed between the light-shielding grids.

4. The viewing angle control panel of claim 1,

a transparent resin is formed between the light-shielding gate and the common electrode.

5. The viewing angle control panel of claim 1,

the light-shielding barrier has a predetermined height that allows the light-shielding barrier to shield light having a polar angle larger than a predetermined polar angle from light passing through the first electrode or light passing through the second electrode.

6. The viewing angle control panel of claim 1,

the light-shielding barrier has a predetermined height such that the light-shielding barrier blocks light having a polar angle larger than a predetermined polar angle in accordance with a voltage applied to the first electrode or a voltage applied to the second electrode.

7. The viewing angle control panel of claim 1,

the light-shielding grids are formed in a stacked manner.

8. The viewing angle control panel of claim 1,

the light-shielding grids are of a laminated structure comprising a first light-shielding grid and a second light-shielding grid,

a transparent resin is formed between the first louver and the first louver, and the transparent resin is formed between the second louver and the second louver in a plan view,

the transparent resin is formed between the first light-shielding grille and the second light-shielding grille in a cross-sectional view.

9. The viewing angle control panel of claim 8,

the width of the light-shielding grids in the second direction is larger than the thickness of the transparent resin between the first light-shielding grids and the second light-shielding grids.

10. A viewing angle control panel which sandwiches a liquid crystal between a first substrate and a second substrate, characterized in that,

a transparent common electrode is formed in a planar shape on the first substrate,

a light-shielding grating extending along a first direction is formed on the second substrate,

a transparent first electrode extending in the first direction and a transparent second electrode extending in the first direction are formed in parallel with a first space on the second substrate to cover the light-shielding grating,

the first electrode and the second electrode constitute an electrode pair, the electrode pair being arranged in a second direction,

the light-shielding gate is formed at a position corresponding to the electrode pair and a space between the electrode pair in a plan view.

11. A viewing angle control panel which sandwiches a liquid crystal between a first substrate and a second substrate, characterized in that,

a transparent common electrode is formed in a planar shape on the first substrate,

a first insulating film is formed so as to cover the common electrode,

a transparent first electrode extending in a first direction and a transparent second electrode extending in the first direction are formed in parallel with a second gap therebetween on the first insulating film, the first electrode and the second electrode form an electrode pair, and the electrode pair is arranged in a second direction,

a light-shielding grating extending in the first direction is formed on the second substrate,

the light-shielding gate is formed at a position corresponding to the electrode pair and a space between the electrode pair in a plan view.

12. The viewing angle control panel of claim 11,

the light-shielding barrier has a predetermined height such that the light-shielding barrier blocks light having a polar angle larger than a predetermined polar angle in accordance with a voltage applied to the first electrode or a voltage applied to the second electrode.

13. A viewing angle control panel which sandwiches a liquid crystal between a first substrate and a second substrate, characterized in that,

transparent first electrodes extending in a first direction and transparent second electrodes extending in the first direction are formed in parallel with each other at first intervals on the first substrate, the first electrodes and the second electrodes form electrode pairs, the electrode pairs are arranged in a second direction,

a first insulating film is formed so as to cover the electrode pair,

a transparent common electrode is formed to cover the first insulating film,

a strip-shaped hole extending in the first direction is formed in the common electrode at a position overlapping with the first electrode and the second electrode,

a light-shielding grating extending in the first direction is formed on the second substrate,

the light-shielding gate is formed at a position corresponding to the electrode pair and a space between the electrode pair in a plan view.

14. The viewing angle control panel of claim 13,

the light-shielding barrier has a predetermined height such that the light-shielding barrier blocks light having a polar angle larger than a predetermined polar angle in accordance with a voltage applied to the first electrode or a voltage applied to the second electrode.

15. A display device having a display panel and a viewing angle control panel, the display device being characterized in that,

the viewing angle control panel according to any one of claims 1 to 14,

the viewing angle control panel is disposed on a front surface of the display panel.

16. The display device according to claim 15,

the display panel is a liquid crystal display panel.

17. The display device according to claim 15,

the display panel is an organic EL display panel.

18. A display device having a display panel, a viewing angle control panel, and a backlight, the display device being characterized in that,

the viewing angle control panel according to any one of claims 1 to 14,

the viewing angle control panel is disposed on a front surface of the display panel.

19. A display device having a display panel, a viewing angle control panel, and a backlight, the display device being characterized in that,

the viewing angle control panel according to any one of claims 1 to 14,

the viewing angle control panel is disposed on a rear surface of the display panel.

20. The display device according to claim 18 or 19,

the display panel is an IPS mode liquid crystal display panel, and the viewing angle control panel is a TN mode liquid crystal panel.

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