WO2014148198A1

WO2014148198A1 - Liquid-crystal display and method for manufacturing liquid-crystal display

Info

Publication number: WO2014148198A1
Application number: PCT/JP2014/054156
Authority: WO
Inventors: 淳子梅澤; 英俊中川; 大樹速井
Original assignee: 堺ディスプレイプロダクト株式会社
Priority date: 2013-03-18
Filing date: 2014-02-21
Publication date: 2014-09-25

Abstract

The provision of a liquid-crystal display and a method for manufacturing a liquid-crystal display wherein a patterned retardation film can be bonded to a liquid-crystal panel with high precision. In this method for manufacturing a liquid-crystal display provided with a liquid-crystal panel comprising a liquid-crystal substance enclosed between a light-transmitting color-filter substrate and a TFT substrate and a patterned retardation film that converts the polarization state of light that has passed through said liquid-crystal panel to two different polarization states, marks are formed on the color-filter substrate at two points that are appropriate distances away, along one edge of the color-filter substrate, from the respective ends of said edge, and using said marks as references, the patterned retardation film is bonded to the liquid-crystal panel.

Description

Liquid crystal display device and method of manufacturing liquid crystal display device

The present invention relates to a liquid crystal display device provided with a pattern retardation film used in passive stereoscopic video display and a method for manufacturing the liquid crystal display device.

As one of the stereoscopic image display methods, a display method using a passive method (polarized glasses method) is known. In this display method, the light emitted from the liquid crystal panel is set to two different polarization states, a polarizing plate that transmits only one polarized light is used for the right eye, and a polarizing plate that transmits only the other polarized light is used for the left eye. By observing the display screen through the configured polarized glasses, the image is recognized as a stereoscopic image.

A pattern retardation film is used in order to change the light emitted from the liquid crystal panel into two different polarization states (see, for example, Patent Document 1). The pattern retardation film includes a pattern retardation layer in which regions having different retardations are regularly arranged. For example, by transmitting linearly polarized light, the linearly polarized light transmitted through each region has two different polarization states. It is configured to convert to circularly polarized light (or elliptically polarized light).

By sticking such a pattern retardation film to a liquid crystal panel, linearly polarized light transmitted through the liquid crystal panel can be converted into two types of circularly polarized light (or elliptically polarized light) having different polarization states. Therefore, the right-eye video and the left-eye video are respectively displayed in one screen, the right-eye video is converted into one polarization state, and the left-eye video is converted into the other polarization state. Thus, the image is recognized as a stereoscopic image when observed through the above-described polarizing glasses.

Japanese Patent No. 4508280 Japanese Patent Laid-Open No. 2007-4111

In the passive stereoscopic image display, one of the two types of retardation regions of the pattern retardation film is made to correspond to the pixel group in the display region for displaying the right-eye image, and the other is used for the left-eye image. Since it is necessary to correspond to the pixel group in the display area to display, the positional accuracy at the time of bonding the pattern phase difference film with respect to a liquid crystal panel was calculated | required.

Conventionally, a technique has been proposed in which a black matrix as a light-shielding layer included in a liquid crystal panel is processed to form a comb-shaped alignment mark indicating the reference of the bonding position, and a polarizing plate is aligned based on such an alignment mark. (For example, refer to Patent Document 2).

However, in order to form the alignment mark described in Patent Document 2, it is necessary to cut out the black matrix on the color filter substrate. Therefore, a gap may be formed in the alignment mark portion. There was concern that light could leak.

The present invention has been made in view of such circumstances, and forms a mark indicating a reference of a bonding position of a pattern retardation film without adding a new process, and by using this mark, a pattern retardation is obtained. An object of the present invention is to provide a liquid crystal display device capable of bonding a film on a color filter substrate with high accuracy and a method for manufacturing the liquid crystal display device.

The liquid crystal display device of the present application includes a liquid crystal panel in which a liquid crystal material is sealed between a light-transmitting color filter substrate and a TFT substrate, and two types of polarization states in which the polarization state of light transmitted through the liquid crystal panel is different. The film for the liquid crystal panel is provided at two locations on the color filter substrate that are separated from each end of the color filter substrate by an appropriate length from both ends of the color filter substrate. A mark for positioning the bonding position is provided.

The liquid crystal display device of the present application is characterized in that the mark is provided at a position separated from the both ends by 10.0 mm or more.

In the liquid crystal display device of the present application, the color filter substrate includes a colored layer that transmits light of a plurality of colors, and a light shielding grid that partitions the colored layer in a lattice pattern, and is made of the same material as the light shielding grid. The mark is formed.

The liquid crystal display device of the present application is characterized in that the mark is formed in a region on the color filter substrate that does not face a wiring pattern provided on a peripheral portion of the TFT substrate.

The liquid crystal display device manufacturing method of the present application includes a liquid crystal panel in which a liquid crystal substance is sealed between a light-transmitting color filter substrate and a TFT substrate, and two types of polarization states of light transmitted through the liquid crystal panel are different. In a manufacturing method of a liquid crystal display device comprising a pattern retardation film for converting to a polarized state of a mark, marks are formed at two positions on the color filter substrate that are separated from each other by an appropriate length from both ends of one side of the color filter substrate. It is characterized by forming.

The manufacturing method of the liquid crystal display device of the present application is characterized in that the mark is formed at a position separated by 10.0 mm or more from the both ends.

The manufacturing method of the liquid crystal display device of the present application is characterized in that the retardation film is bonded to the liquid crystal panel based on the formed mark.

The method of manufacturing a liquid crystal display device according to the present application includes: a color layer that transmits light of a plurality of colors; and a light-shielding lattice that partitions the colored layer in a lattice pattern on a light-transmitting substrate. The mark is formed in the same step as the step of forming a substrate and forming the light-shielding grating on the light-transmitting substrate.

According to the present application, it is possible to form a mark on the color filter substrate that indicates the reference of the bonding position of the pattern retardation film without adding a new process. Since this mark does not exist in the four corner regions of the color filter substrate, even if the sealing material bulges out near the four corners of the substrate when sealing the liquid crystal material between the substrates, the mark is not hidden by the sealing material. The pattern retardation film can be bonded with reference to the marks with certainty.

It is a figure which shows schematic structure of the liquid crystal display device which concerns on this Embodiment. It is sectional drawing of the liquid crystal display device which concerns on this Embodiment. It is a top view which shows an example of an FPR film. It is a longitudinal cross-sectional view which shows an example of an FPR film. It is a schematic diagram which shows an example of the image | video displayed in the case of a three-dimensional video display. It is a schematic diagram which shows an example of the formation position of an alignment mark. It is the elements on larger scale of the neighborhood field of an alignment mark. FIG. 8 is a cross-sectional view taken along line AA shown in FIG. It is a schematic diagram which shows the other shape of an alignment mark. It is a schematic diagram which shows the process of forming an alignment mark on a CF side glass substrate. It is a schematic diagram which shows the other example of the formation position of an alignment mark.

The present invention will be specifically described with reference to the drawings showing the embodiments thereof.
Embodiment 1 FIG.
FIG. 1 is a diagram showing a schematic configuration of a liquid crystal display device according to the present embodiment, and FIG. 2 is a cross-sectional view of the liquid crystal display device according to the present embodiment. The liquid crystal display device according to the present embodiment includes a liquid crystal panel 100, a pattern retardation film (hereinafter referred to as an FPR film 200 (FPR: Film-type Patterned Retarder)) bonded to the liquid crystal panel, and a backlight unit 300. .

The liquid crystal panel 100 includes a TFT side glass substrate 110 (TFT: Thin-Film transistor), a liquid crystal layer 120 formed by sealing a liquid crystal substance, a CF side glass substrate 130 (CF: Color Filter), and the like. On the one side of the TFT side glass substrate 110, a pixel electrode 111 corresponding to each pixel, a TFT 112 connected to the pixel electrode 111, and an alignment film 113 are laminated.
Further, the CF side glass substrate 130 has, on one side thereof, for example, colored layers 11 to 13 (see FIG. 10) that transmit light of colors corresponding to RGB colors, and the colored layers 11 to 13 are arranged in a lattice shape. A color filter 131 including a light shielding grid 15 (see FIG. 10) partitioned by a black matrix as a pattern, a counter electrode 132, and an alignment film 133 are stacked.

A backlight unit 300, a diffusion plate 301, and a polarizing plate 135 are provided on the back side of the liquid crystal panel 100 (the other side of the TFT side glass substrate 110). A polarizing plate 134 is provided on the front side of the liquid crystal panel 100 (the other side of the CF side glass substrate 130).

The backlight unit 300 is, for example, an edge light type backlight having a light source that emits light to the light guide plate from the side and a light guide plate that emits light incident from the side to the LCD module side, or the TFT side It is comprised by the direct type | mold LED backlight provided with several LED arrange | positioned so that the glass substrate 110 may be opposed.

The diffusion plate 301 is disposed between the polarizing plate 135 and the backlight unit 300 and has a function of diffusing light emitted from the backlight unit 300 toward the liquid crystal panel 100.
The polarizing plate 135 is disposed on the surface of the TFT side glass substrate 110, and the polarizing plate 134 is disposed on the surface of the CF side glass substrate 130. The polarizing

plates

134 and 135 are provided so as to transmit linearly polarized light orthogonal to each other.

With such a configuration, the linearly polarized light transmitted through the polarizing plate 135 out of the light emitted from the backlight unit 300 passes through the liquid crystal layer 120 and enters the CF side polarizing plate 134. At this time, the polarization state of the light transmitted through the liquid crystal layer 120 can be changed by a voltage applied to the liquid crystal layer 120. Therefore, a voltage corresponding to the video signal is applied to the pixel electrode 111 and the counter electrode 132, and an electric field is applied to the liquid crystal layer 120, thereby changing the polarization state of the light passing through the liquid crystal layer 120 and passing through the polarizing plate 134. An optical image can be formed by controlling the amount of light to be emitted.

The liquid crystal display device according to the present embodiment includes the FPR film 200 separately from the

polarizing plates

134 and 135 provided on both sides of the liquid crystal panel 100, and enables stereoscopic image display. The FPR film 200 converts linearly polarized light transmitted through the

polarizing plates

134 and 135 into two types of polarized light (for example, circularly polarized light) having different polarization states.

FIG. 3 is a plan view showing an example of the FPR film 200, and FIG. 4 is a longitudinal sectional view thereof. The FPR film 200 includes, for example, a first region 201 and a second region 202 that are different from each other in at least one of an in-plane slow axis and an in-plane retardation, and the first region 201 and the second region 202 are alternately arranged. It has a striped pattern. Each of the first region 201 and the second region 202 has a strip shape extending in parallel to the lateral direction (X-axis direction shown in the drawing). The FPR film 200 converts the linearly polarized light transmitted through the first region 201 into, for example, right circularly polarized light, and converts the linearly polarized light transmitted through the second region 202 into, for example, left circularly polarized light. Creating a state.

The stripe pattern in the FPR film 200 is set according to the position of the pixel provided in the liquid crystal panel 100. Further, the width in the vertical direction (Y-axis direction shown in FIG. 3) of the first region 201 and the width in the vertical direction of the second region 201 can be set according to the dimensions of the pixels of the liquid crystal panel 100. When stereoscopic image display is performed on the liquid crystal display device, as will be described later, a right-eye image for observation with the right eye and a left-eye image for observation with the left eye are displayed in the display area of the liquid crystal panel 100. indicate. By making one of the right-eye video and the left-eye video correspond to the first region 201 of the FPR film 200 and the other to the second region 202 of the FPR film 200, the right-eye video is a right circle. Polarized (or left-circularly polarized) optical characteristics, and the left-eye image has left-circularly polarized (or right-circularly polarized) optical characteristics. As a result, a polarizing plate that transmits only one polarized light is used for the right eye and a polarizing plate that transmits only the other polarized light is used for the left eye. Be recognized.

FIG. 5 is a schematic diagram showing an example of an image displayed during stereoscopic image display. In the present embodiment, when stereoscopic video display is performed on the liquid crystal display device, the right-eye video and the left-eye video are alternately displayed in the display area of the liquid crystal panel 100 line by line. For example, when the liquid crystal panel 100 has a resolution of full HD (that is, 1920 dots × 1080 lines), a right eye image and a left eye image for 1920 dots × 540 lines are prepared, as shown in FIG. The right eye image and the left eye image are alternately displayed line by line.
In FIG. 5, for the sake of simplification, a three-dimensional image including nine lines R1 to R9 for the right eye and nine lines L1 to L9 for the left eye is shown.

In the passive stereoscopic video display system, it is necessary to convert the polarization state of the right-eye video and the left-eye video into different polarization states. Therefore, the FPR for the liquid crystal panel 100 is set so that the positions of the right-eye video and the left-eye video for each line correspond to the positions of the first region 201 and the second region 202 of the FPR film 200. The film 200 is bonded. In this embodiment, one of the features is that an alignment mark 16 (see FIG. 6) for positioning the bonding position of the FPR film 200 to the liquid crystal panel 100 is formed on the CF-side glass substrate 130. By using the position of the alignment mark 16 as a reference, the position of the pixel (more specifically, the pixel group of each line displaying the image for the right eye and the image for the left eye) formed on the CF side glass substrate 130 is set. It becomes possible to make each phase area of FPR film 200 correspond.

FIG. 6 is a schematic diagram showing an example of the position where the alignment mark 16 is formed. The CF side glass substrate 130 is provided with a display area 10 formed by the colored layers 11 to 13 and the light shielding grid 15, and a frame portion 20 formed in the same process as the light shielding grid 15 around the display area 10. Is provided. A seal region 30 where a sealing material 31 (see FIG. 8) for sealing a liquid crystal material is drawn between the CF side glass substrate 130 and the TFT side glass substrate 110 exists on the outer side of the frame portion 20. To do.
In addition, a plurality of TFT side tabs 60 including a wiring pattern connected to the TFT 112 and the like are provided on the peripheral portion on one side of the TFT side glass substrate 110.

The alignment marks 16 are formed at two locations on one side of the substrate on the one surface side of the CF side glass substrate 130. In the example shown in FIG. 6, the alignment marks 16 and 16 are formed at two locations on the upper side and the lower side of the CF side glass substrate 130, respectively. The structure which forms may be sufficient. Moreover, the

alignment mark

16,16 formed in two places of the left side of CF side glass substrate 130, or two places of the right side may be included. Furthermore, the number of alignment marks 16 per side is not limited to two, and may be three or more.

Each alignment mark 16 is preferably formed at a position separated from the four corners of the CF side glass substrate 130 by an appropriate length (for example, 10.0 mm or more) along one side. In the sealing region 30 of the CF side glass substrate 130, the sealing material 31 is drawn when the liquid crystal substance is sealed. However, the drawing speed is reduced in the regions near the four corners of the substrate, so the other regions In many cases, the width of the sealing material 31 is thick and finished. That is, in the region near the four corners of the CF side glass substrate 130, the sealing material 31 may spread outward in the plane, and even if the alignment mark 16 is formed near this region, it is difficult to observe from the outside. There is a possibility. Therefore, in the present embodiment, the alignment marks 16 are formed excluding regions near the four corners of the substrate.

Further, each alignment mark 16 is preferably formed in a region that does not face the TFT side tab 60 provided on the TFT side glass substrate 110. Since the TFT side tab 60 has a wiring pattern connected to the TFT 112 or the like, when such a wiring pattern and the alignment mark 16 face each other in the thickness direction of the liquid crystal panel 100, the alignment mark 16 is recognized from the outside. It is difficult to do.

Further, as shown in FIG. 6, when the alignment marks 16 are formed at two locations on the upper side and the lower side of the CF-side glass substrate 130, respectively, in positions symmetrical with respect to the vertical direction of the substrate, It is preferable to form two alignment marks 16 and 16 on the upper side and two alignment marks 16 and 16 on the lower side.
By forming the alignment marks 16 and 16 at positions symmetrical with respect to the vertical direction of the substrate, even if a reading failure occurs in the two alignment marks 16 and 16 on the upper side (or the lower side), the liquid crystal panel 100 By reversing the upper and lower sides, the other two alignment marks 16 and 16 can be read.

7 is a partially enlarged view of a region near the alignment mark 16, and FIG. 8 is a cross-sectional view taken along the line AA shown in FIG. The alignment mark 16 has a square shape of about 0.2 mm × 0.2 mm. For example, the alignment mark 16 is formed on the CF side glass substrate 130 with the same material as the light shielding grid 15 in the same process as the process for forming the light shielding grid 15 (black matrix). Formed. The camera field of view for reading the alignment mark 16 is an area of about 3.8 mm × 3.8 mm, and it is desirable that there is no similar pattern that causes an error in reading the alignment mark 16 in this area. For this reason, the alignment mark 16 is formed in a region outside the sealing region 30 where the sealing material 31 is formed and in a region not facing the wiring pattern of the TFT side tab 60 in the thickness direction of the liquid crystal panel 100.

In the present embodiment, the alignment mark 16 has a square shape, but is not limited to a square shape. FIG. 9 is a schematic diagram showing another shape of the alignment mark 16. As the shape of the alignment mark 16, in addition to a square, a circle (FIG. 9A), a cross (FIG. 9B), a triangle (FIG. 9C), or the like can be used. Further, the mark may have an appropriate shape as shown in FIGS. 9D to 9F.

FIG. 10 is a schematic diagram showing a process of forming the alignment mark 16 on the CF side glass substrate 130. As described above, the alignment mark 16 can be formed in the same process as the process of forming the light shielding grid 15 on the CF side glass substrate 130. The light shielding grid 15 is formed by a photolithography technique using a black photoresist.

First, after forming a translucent substrate (CF side glass substrate 130) such as a glass substrate (FIG. 10A), a photoresist having a thickness of about 1 μm is applied by applying a black photoresist to one side of the substrate. Layer 130b is formed (FIG. 10B).

Thereafter, the surface of the photoresist layer 130b is exposed using a photomask in which a pattern to be projected is formed of a light-shielding film such as chromium (Cr), and unnecessary portions are removed by development processing (FIG. 10C). By this process, the portion corresponding to the pixel in the display region 10, the photoresist region 130 b applied to the region excluding the seal region and the alignment mark 16 is removed, and the alignment mark 16, the frame portion 20, and the display region 10 in the display region 10 are removed. A light shielding grid 15 is formed.

Next, a photoresist layer 130r having a thickness of about 1 μm is formed on the entire surface of the substrate on which the light shielding grid 15 is formed by applying a photoresist that transmits light of a specific color (for example, red) (FIG. 10D). Then, the photoresist layer 130r is exposed and developed using a photomask for forming a pixel pattern, thereby forming a colored layer 11 (pixel) that transmits light of a specific color with a predetermined pixel pattern. (FIG. 10E). In the same process, the

colored layers

12 and 13 corresponding to other colors (for example, green and blue) are formed on the CF side glass substrate 130 (FIG. 10F).

The FPR film can be bonded to the other surface side of the CF side glass substrate 130 with the position of the alignment mark 16 formed in this way as a reference. A line segment connecting the two alignment marks 16 and 16 formed on the upper side (or the lower side) of the CF side glass substrate 130 is parallel to a horizontal pixel line in the display region 10 (X-axis direction shown in FIG. 3). Become. Therefore, the line segment connecting the two alignment marks 16, 16 is parallel to the first region 201 and the second region 202 (for example, the boundary line between the first region 201 and the second region 202) of the FPR film 200. By positioning and bonding the CF side glass substrate 130 and the FPR film 200, each phase region of the FPR film 200 is made to correspond to the position of the pixel group of each line displaying the right eye image and the left eye image. Can do.

In the present embodiment, the alignment mark 16 is formed using the same material as the light-shielding grating 15, but the colored layers 11 to 13 are formed using the same material as the colored layers 11 to 13. The alignment mark 16 may be formed in the same process as the process. The alignment mark 16 may have any one of a single layer structure using a black matrix, a single layer structure using the colored layers 11 (12, 13), and a stacked structure of the black matrix and the colored layers 11 to 13. Further, when the signal wiring (metal) conventionally formed on the TFT side glass substrate 110 is formed on the CF side glass substrate 130, the alignment mark 16 may be formed using the same material as the signal wiring.

Embodiment 2. FIG.
In the first embodiment, the alignment mark 16 is formed at a position that is symmetric with respect to the vertical direction of the CF side glass substrate 130. However, some pattern on the CF side glass substrate 130 (for example, connected to the counter electrode 132). If the alignment mark 16 cannot be formed symmetrically or vertically symmetrical due to interference with the wiring pattern), the alignment mark 16 may be formed at another position.
In the following description, the same components as those in the first embodiment will be described with the same reference numerals as those in the first embodiment.

FIG. 11 is a schematic diagram showing another example of the position where the alignment mark 16 is formed. As in the first embodiment, the alignment marks 16 are formed at two locations on one side of the substrate on one side of the CF side glass substrate 130. In the example shown in FIG. 11, alignment marks 16 are formed at two locations on the left side and the right side of the CF side glass substrate 130. Although these alignment marks 16 and 16 are not left-right symmetric, they are provided at point-symmetrical positions with respect to the center of the substrate. Therefore, as in the first embodiment, even if a reading failure occurs in the two alignment marks 16 and 16 on the left side (or right side), the other two alignment marks 16 are inverted by turning the liquid crystal panel 180 degrees. , 16 can be continued.

In the first and second embodiments, the alignment mark 16 is formed at a line-symmetrical or point-symmetrical position in the plane of the substrate, but the symmetrical position is not an essential requirement. Two alignment marks 16 may be formed at asymmetric positions on the upper side and the lower side (or the left side and the right side).

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. In addition, the technical features described in each embodiment can be combined with each other.

100 Liquid crystal panel 110 TFT side glass substrate 111 Pixel electrode 112 TFT
DESCRIPTION OF SYMBOLS 113 Alignment film 120 Liquid crystal layer 130 CF side glass substrate 131 Color filter 132 Counter electrode 133 Alignment film 134,135 Polarizing plate 200 FPR film 300 Backlight unit 301 Diffusion plate

Claims

A liquid crystal panel in which a liquid crystal material is sealed between a light-transmitting color filter substrate and a TFT substrate, and a pattern retardation film for converting the polarization state of light transmitted through the liquid crystal panel into two different polarization states In a liquid crystal display device comprising:
A mark for positioning a bonding position of the film with respect to the liquid crystal panel is provided at two positions on the color filter substrate that are spaced apart from each other by an appropriate length from both ends of the one side of the color filter substrate. A liquid crystal display device.
2. The liquid crystal display device according to claim 1, wherein the mark is provided at a position separated by 10.0 mm or more from the both ends.
The color filter substrate includes a colored layer that transmits light of a plurality of colors, and a light-shielding lattice that partitions the colored layer in a lattice pattern,
The liquid crystal display device according to claim 1, wherein the mark is formed of the same material as the light shielding grid.
4. The mark according to claim 1, wherein the mark is formed in a region on the color filter substrate that is not opposed to a wiring pattern provided on a peripheral portion of the TFT substrate. 5. Liquid crystal display device.
A liquid crystal panel in which a liquid crystal material is sealed between a light-transmitting color filter substrate and a TFT substrate, and a pattern retardation film for converting the polarization state of light transmitted through the liquid crystal panel into two different polarization states In a manufacturing method of a liquid crystal display device comprising:
2. A method of manufacturing a liquid crystal display device, comprising: forming marks at two locations on the color filter substrate that are spaced apart from each other by an appropriate length from both ends of the one side of the color filter substrate.
6. The method of manufacturing a liquid crystal display device according to claim 5, wherein the mark is formed at a position separated from the both ends by 10.0 mm or more.
The method for manufacturing a liquid crystal display device according to claim 5, wherein the retardation film is bonded to the liquid crystal panel based on the formed mark.
Forming the color filter substrate by forming a colored layer that transmits light of a plurality of colors and a light-shielding grating that partitions the colored layer in a lattice-like pattern on the light-transmitting substrate;
The liquid crystal display device manufacturing method according to any one of claims 5 to 7, wherein the mark is formed in the same step as the step of forming the light-shielding grating on the light-transmitting substrate. Method.