JP2000221462A - Production of electro-optic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To embody a process for producing an electro-optic device capable of improving a display grade by eliminating the offset in the alignment direction of an electro-optic material. SOLUTION: In the process for producing the electro-optic panel 1, a rubbing treatment is executed after the position and direction of an active matrix substrate 30 are aligned on the basis of alignment marks 38A, 38B, 38C and 38D for assembly formed on the active matrix substrate 30. After the active matrix substrate 30 and a counter substrate are bonded to each other on the basis of the alignment marks 38A, 38B, 38C and 38D for assembly, the polarizing plate is bonded on the basis of the alignment marks 38A, 38B, 38C and 38D for assembly or the alignment marks for positioning the polarizing plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electro-optical device having an electro-optical panel in which an electro-optical material is held between a pair of substrates. More specifically, the present invention relates to a technique for manufacturing an electro-optical device that performs display using polarized light.

[0002]

2. Description of the Related Art As a display device (electro-optical device) equipped with an electro-optical panel using an electro-optical material such as a liquid crystal, there are an active matrix drive type and a passive matrix drive type. An electro-optical panel used as a light valve in a display device employs an active matrix driving system.

In an electro-optical panel of this type, as schematically shown in FIG. 4, an active matrix substrate on which a pixel electrode 8, an alignment film 46, a pixel switching thin film transistor (hereinafter referred to as TFT) 10 and the like are formed. 3
0, a counter substrate 20 on which a counter electrode 32 and an alignment film 47 are formed, and a liquid crystal 39 sealed and sandwiched as an electro-optical material between these substrates. The active matrix substrate 30 and the opposing substrate 20 are bonded to each other with a predetermined gap by a sealing material 52 containing a gap material, and a liquid crystal 39 is sealed in the gap.

Here, the alignment films 46 and 47 are formed by performing a rubbing process in a predetermined direction on an organic thin film such as a polyimide film, and are formed between the active matrix substrate 30 and the counter substrate 20. When the liquid crystal 39 is sealed, the alignment state of the liquid crystal 39 is defined.

In such a rubbing process, the rubbing direction (direction indicated by arrow A) with respect to the active matrix substrate 30 is usually as shown in FIG.
And the rubbing direction (direction indicated by arrow B) with respect to the opposing substrate 20 are set to be at a right angle. For this reason,
In a state where no electric field is applied, the liquid crystal 39 receives an alignment regulating force from the alignment films 46 and 47 near the surfaces of the active matrix substrate 30 and the counter substrate 20, and twists and aligns at an angle of 90 ° between the substrates (TN). mode). Such a twisted orientation is released by applying an electric field between the active matrix substrate 30 and the counter substrate 20, as shown in FIG. Therefore,
The alignment state of the liquid crystal 39 can be controlled depending on whether or not an external electric field is applied. Therefore, in the case of the transmissive electro-optical panel 1, light L from a light source (not shown)
After being adjusted to predetermined linearly polarized light by the incident side polarizing plate 12, the light enters the liquid crystal 39 layer from the counter substrate 20 side,
As shown in FIG. 10A, in a pixel to which no electric field is applied, the transmission polarization axis is twisted and emitted from the active matrix substrate 30. On the other hand, as shown in FIG. 10B, an electric field is applied. In the pixel, the transmitted polarization axis is emitted from the active matrix substrate 30 without being twisted. Therefore, as shown in FIGS. 10A and 10B,
If the output side polarizing plate 11 is arranged so that the incident side polarizing plate 12 and the transmission polarization axis are orthogonal (normally white), the light passes through the polarizing member 11 arranged on the output side of the electro-optical panel 1. This is only the linearly polarized light whose transmission polarization axis is twisted by the liquid crystal 39. On the other hand, if the output-side polarizing plate 11 is arranged so that the transmission-side polarization axis is parallel to the incident-side polarizing plate 12 (normally black), the output-side polarizing plate 11 is disposed on the output side of the electro-optical panel 1. Only linearly polarized light whose transmission polarization axis is not twisted by the liquid crystal 39 passes through the polarizing member 11. Therefore, predetermined information can be displayed by controlling these polarization states for each pixel. Further, if an enlarged projection optical system is arranged on the emission side of the electro-optical panel 1, an image formed by the electro-optical panel 1 can be enlarged and projected on a projection surface such as a screen.

As described above, in the electro-optical panel 1, since display is performed using polarized light, the polarizing plate 12 on the incident side, the rubbing direction with respect to the counter substrate 20, the rubbing direction with respect to the active matrix substrate 30, and the polarizing plate on the emission side are used. It is necessary to adjust each direction of 11 in accordance with predetermined conditions.

Therefore, conventionally, small polarizing plates 11 and 12 that can be attached to the electro-optical panel 1 from a large polarizing plate.
When the electro-optical panel 1 is divided into rectangular sections, the polarizers 11 and 12 are also cut out into rectangles, and the polarizers 11 and 12 are divided into rectangular sections based on the sides and corners.
After adjusting the direction above, it is pasted with adhesive. Further, when performing the rubbing process, the active matrix substrate 30 and the counter substrate 20 are each rectangular, so that the rubbing direction is set based on the sides and the like.

[0008]

However, in a display device using the electro-optical panel 1, an improvement in display quality is strongly demanded. For example, when an attempt is made to achieve a high definition display, a pixel switching device is required. Size restrictions on devices such as TFTs increase, and device characteristics cannot be maintained. Further, in the projection type display device, the output from the light source tends to be increased in order to perform display with higher brightness, but the contrast ratio is reduced accordingly. In order to improve the contrast ratio, improvement of device characteristics, improvement of bonding accuracy between substrates, and improvement of cell thickness accuracy have been studied, but at present it has not yet been achieved to a sufficient level. .

Accordingly, an object of the present invention is to provide a method of manufacturing an electro-optical device capable of improving display quality by eliminating a shift in the orientation direction of an electro-optical material, which has not been noticed hitherto. It is in.

[0010]

According to the present invention, there is provided a thin film formed on a pair of substrates for sandwiching an electro-optical material by subjecting the thin film to a rubbing process in a predetermined direction. A rubbing process using an alignment film, a substrate bonding process of bonding the pair of substrates having been subjected to the rubbing process so that the alignment films face each other via a predetermined gap, and a substrate bonding process. And a filling step of filling an electro-optical substance between a pair of substrates bonded together in the electro-optical device, in the rubbing step, the substrate is subjected to a predetermined process based on a mark previously attached to the substrate. A rubbing process is performed after the orientation is adjusted.

In the present invention, the rubbing process is performed by aligning the orientation of the substrate with reference to a mark previously attached to the substrate. Even if the side of the substrate is inclined when the substrate is cut out, the substrate can be arranged in an accurate direction when performing the rubbing process. Therefore, since the rubbing treatment can be performed in a predetermined direction, the transmission polarization axis of the polarizing plate can be adjusted to the orientation direction of the electro-optical material only by appropriately attaching the polarizing plate later. Therefore, according to the present invention, high-quality display can be performed in an electro-optical device such as a projection display device.

In the present invention, in the substrate bonding step, the pair of substrates is bonded in a predetermined direction based on the mark, and then the pair of substrates is bonded. . In this embodiment, the rubbing direction is set based on the mark for assembly, that is, after the pair of substrates are aligned in a predetermined direction based on the mark, and then the rubbing direction is set based on the mark. Deviation can be suppressed.

In the present invention, the method further comprises the step of attaching a polarizing plate to at least one substrate surface of the pair of substrates. In the step of attaching the polarizing plate, the pair of substrates is fixed to a predetermined position based on the mark. After the orientation, the polarizing plate may be attached to the substrate. In this embodiment, since the rubbing direction is set based on the mark, no deviation occurs between the transmission polarization axis of the polarizing plate and the rubbing direction when the polarizing plates are bonded.

According to another aspect of the present invention, a rubbing process in a predetermined direction is performed on a thin film formed on a surface of a pair of substrates for sandwiching an electro-optical material to make the thin film an alignment film. A substrate bonding step of bonding the pair of substrates having been subjected to the rubbing treatment step such that the alignment films face each other with a predetermined gap therebetween, and between the pair of substrates bonded in the substrate bonding step. Forming a first mark for assembling on the substrate and a second mark for attaching a polarizing plate to the substrate at the same time at a predetermined interval. In the rubbing process, the rubbing process is performed after the substrate is oriented in a predetermined direction based on at least one of the first and second marks. And butterflies.

According to this structure of the present invention, since the first mark and the second mark are formed simultaneously from the same material, there is no displacement or inclination between the two marks. In addition, rubbing can be performed with high accuracy even if rubbing is performed using either mark as a reference, and the rubbing direction, the bonding between the substrates, and the bonding of the polarizing plate to the substrate can be performed with high accuracy. In another embodiment of the present invention, a rubbing process in a predetermined direction is performed on a thin film formed on a surface of a pair of substrates for sandwiching an electro-optical material to make the thin film an alignment film; A substrate bonding step of bonding the pair of substrates having been subjected to the processing step so that the alignment films face each other with a predetermined gap therebetween, and an electro-optical material between the pair of substrates bonded in the substrate bonding step. And a filling step of filling the substrate with a rubbing mark indicating a direction in which the rubbing process has been performed in the rubbing step in conjunction with the rubbing operation.

In the present invention, a rubbing mark indicating the direction in which the rubbing process was performed in the rubbing process is added to the substrate in conjunction with the rubbing process. An inspection or the like can be performed to determine whether or not the operation has been performed normally. Also,
The rubbing mark indicates the actual rubbing direction.Therefore, if the rubbing mark is used as a reference for positioning the substrates and determining the position and orientation of the polarizing plate, even if the rubbing direction is misaligned, The electro-optical device can be configured based on the rubbing direction. That is,
The deviation in the rubbing direction can be corrected. Therefore,
According to the present invention, in the present invention capable of performing high-quality display in an electro-optical device such as a projection display device, in the substrate bonding step, the substrates are oriented in a predetermined direction based on the rubbing mark. After the bonding, the substrates are preferably bonded to each other. In the present embodiment, since the substrates are bonded based on the rubbing marks, the substrates are bonded in the rubbing direction actually performed. Therefore, there is no deviation between the bonded substrate and the rubbing direction.

It is preferable that the polarizing plate is aligned with at least one of the pair of substrates based on the rubbing mark, and then the substrate and the polarizing plate are bonded. In the present embodiment, since the direction and position of the polarizing plate are adjusted based on the rubbing mark, the polarizing plate is attached to the substrate in accordance with the rubbing direction actually performed. Therefore, there is no deviation between the transmission polarization axis of the attached polarizing plate and the rubbing direction.

According to the method for manufacturing an electro-optical device, a light source, a condensing optical system for guiding light emitted from the light source to the electro-optical panel, and a light It is suitable for manufacturing a projection display device in which an enlarged projection optical system for enlarging and projecting the generated light is arranged.

[0019]

Embodiments of the present invention will be described with reference to the drawings.

[Structure of Main Parts of Projection Display Device] FIG.
FIG. 2 is an overall configuration diagram of a projection display device (electro-optical device) showing an example of use of the electro-optical panel of the embodiment.

In FIG. 1, an optical unit 2010 is mounted in a housing of the projection display device 2001, and a light source lamp 2011 is installed in the optical unit 2010.
(Light source), integrator lenses 2012 and 2014 formed of an aggregate of minute lenses, and a polarization separation film and λ
An illumination optical system 2015 including a polarization conversion element 2016 formed of an aggregate with a 波長 wavelength plate;
A color separation optical system 2020 that separates a white light beam emitted from 15 into red, green, and blue color light beams R, G, and B, and three liquid crystal light valves 2030R and 2030G as light valves that modulate each color light beam. , 2030B, a prism unit 2042 composed of a dichroic prism as a color synthesizing optical system for re-synthesizing the modulated color light beam, and a projection lens unit 2050 (projection optical system) for enlarging and projecting the synthesized light beam on a screen. It is configured.
As the light source lamp 2011, a halogen lamp, a metal halide lamp, a xenon lamp, or the like can be used. In the optical unit 2010, the polarization conversion element 20
P-polarized light and S separated by each prism body at 16
Since this corresponds to a configuration in which a λ / 2 plate is arranged at the emission position of P-polarized light, the light beam can be aligned with S-polarized light.

The illumination optical system 2015 includes a reflection mirror 201.
7, the central optical axis of the illumination optical system 2015 is bent at a right angle toward the front of the apparatus. The color separation optical system 2020 includes a red-green reflection dichroic mirror 2022, a green reflection dichroic mirror 2024,
A reflection mirror 2026 is provided. Light source lamp 2
The white light beam emitted from the illumination optical system 201
After passing through No. 5, first, a red-green reflecting dichroic mirror 202
At 2, the red light flux R and the green light flux G contained therein are reflected at a right angle and directed toward the green reflection dichroic mirror 2024. The blue light flux B passes through the red-green reflecting dichroic mirror 2022, is reflected at a right angle by the rear reflecting mirror 2026, and is emitted from the emission part of the blue light flux toward the prism unit 2042. The red and green light fluxes R and G reflected by the red-green reflective dichroic mirror 2022 are combined with the green reflective dichroic mirror 2.
At 024, only the green luminous flux G is reflected at a right angle,
The green light flux is emitted from the emission unit to the prism unit 2042 side. On the other hand, the red light flux R that has passed through the green reflection dichroic mirror 2024 is emitted from the emission part of the red light flux to the light guide system 2044 side. Color separation optical system 2
Condensing lenses 2027R, 2027G, and 2027B are arranged on the emission side of each color light beam at 020, respectively. Therefore, each color light beam emitted from each emission unit is
These condenser lenses 2027R, 2027G, 2027
B and each liquid crystal light valve 2030R, 2030
G, 2030B (electro-optical panel 1). As described above, in the present embodiment, the illumination optical system 2015, the color separation optical system 2020, and the condenser lenses 2027R and 2027
G, 2027B and the light guide system 2044 constitute a light condensing optical system that condenses light emitted from the light source lamp 2011 and guides the light to each of the liquid crystal light valves 2030R, 2030G, and 2030B.

The light beams R, G, and B of the respective colors thus condensed
Among them, the blue and green luminous fluxes B and G enter the liquid crystal light valves 2030B and 2030G and are modulated, and image information (video information) corresponding to each color light is added. That is, these light valves are switching-controlled by drive means (not shown) in accordance with the image information, whereby the modulation of each color light passing therethrough is performed. As such a driving means, a known means can be used as it is.

On the other hand, the red light flux R is guided to the liquid crystal light valve 2030R via the light guide system 2044, where it is similarly modulated according to image information. In addition,
As the light guide system 2044, the incident side lens 2045, the incident side reflection mirror 2046, and the exit side reflection mirror 2047
And an intermediate lens 2048 disposed therebetween.

Next, each liquid crystal light valve 2030R,
Each color light flux modulated through 030G and 2030B is
The light enters the prism unit 2042 and is recombined. The recombined color image is enlarged and projected on a screen (projection surface) at a predetermined position via the projection lens unit 2050.

[Overall Configuration of Electro-Optical Panel] FIGS. 2 and 3 show the configuration of the electro-optical panel 1 used as each of the liquid crystal light valves 2030R, 2030G, and 2030B in the projection display device 2001 thus configured. I will explain.

FIGS. 2 and 3 are a plan view of the electro-optical panel according to the present embodiment as viewed from the counter substrate side and a cross-sectional view of the electro-optical panel taken along line HH 'in FIG. .

2 and 3, the electro-optical panel 1 has an active matrix substrate 30 on which pixel electrodes 8 are formed in a matrix, an opposing substrate 20 on which opposing electrodes 32 are formed, and an electrical connection between these substrates. A liquid crystal 39 sealed and held as an optical substance is roughly constituted. The active matrix substrate 30 and the counter substrate 20 are bonded to each other via a predetermined gap by a sealing material 52 containing a gap material formed along the outer peripheral edge of the counter substrate 20. The active matrix substrate 30
A liquid crystal enclosing region 40 is defined between the substrate and the counter substrate 20 by a sealing material 52 containing a gap material, and a liquid crystal 39 is sealed in the liquid crystal enclosing region 40. As the sealing material 52, an epoxy resin, various ultraviolet curable resins, or the like can be used.

The opposing substrate 20 is smaller than the active matrix substrate 30, and the peripheral portion of the active matrix substrate 30 is bonded so as to protrude from the outer peripheral edge of the opposing substrate 20. Therefore, the active matrix substrate 30
Drive circuits (scanning line drive circuit 70 and data line drive circuit 6)
0) and the input / output terminals 45 are exposed from the counter substrate 20. Here, since the sealing material 52 is partially interrupted, the liquid crystal injection port 241 is formed by the interrupted portion. For this reason, after the opposing substrate 20 and the active matrix substrate 30 are bonded to each other, if the inner region of the sealing material 52 is set in a reduced pressure state, the liquid crystal 39 can be injected under reduced pressure from the liquid crystal injection port 241, and The liquid crystal injection port 241 may be closed with the sealant 242. The counter substrate 20 has a screen display area 7 inside the sealing material 52.
A light-shielding film 55 for cutting off is also formed. In each of the corners of the opposing substrate 20, a vertical conducting material 56 for establishing electric conduction between the active matrix substrate 30 and the opposing substrate 20 is formed.

The light incident side surface or the light exit side of the opposing substrate 20 and the active matrix substrate 30 is
The type of the liquid crystal 39 to be used, that is, an operation mode such as a TN (twisted nematic) mode, an STN (super TN) mode, a D-STN (double-STN) mode, and a normally white mode / normally black mode. Thus, a retardation film, a polarizing member, and the like are arranged in a predetermined direction.

Here, the electro-optical panel 1 of the present embodiment is used in the projection display device (liquid crystal projector) described with reference to FIG. In this projection type display device, light from a light source (not shown) is adjusted to predetermined linearly polarized light by a polarizing plate (not shown) on the incident side, and then enters the counter substrate 20. Therefore, in the example shown in FIG. 3, the outer surface 301 of the active matrix substrate 30 out of the opposing substrate 20 and the active matrix substrate 30.
The sheet-like polarizing member 11 made of plastic is adhered only to the (outgoing side) with the translucent adhesive 211.

In the projection display device described with reference to FIG. 1 among the display devices using the electro-optical panel 1, three electro-optical panels 1 are used as RGB light valves, respectively. Each of the electro-optical panels 1 includes:
The light of each color separated via the dichroic mirror for RGB color separation is respectively incident as projection light. Therefore, no color filter or the like is formed on the electro-optical panel 1 of the present embodiment. However, in addition to the projection type liquid crystal display, a color electro-optical panel such as a color liquid crystal television is formed by forming an RGB color filter together with a protective film in a region facing each pixel electrode 8 on the counter substrate 20. Can be. Furthermore, a dichroic filter that creates RGB colors by utilizing the interference effect of light may be formed by laminating a number of interference layers having different refractive indexes on the counter substrate 20. According to the counter substrate with the dichroic filter, a brighter color display can be performed.

[Structure of Each Substrate] FIG. 4 is a cross-sectional view schematically showing a structure for bonding an active matrix substrate and a counter substrate used in the electro-optical panel according to the present embodiment.

In FIG. 4, the electro-optical panel 1 of the present embodiment is shown.
Has a basic structure similar to that used conventionally, and a detailed description thereof will be omitted. However, a scanning line (not shown) is provided on the surface of the active matrix substrate 30. ) And a pixel switching TFT 10 connected to a data line (not shown);
And a transparent pixel electrode 8 connected to the pixel are formed in a matrix. Also, on the surface of the pixel electrode 8,
An alignment film 46 formed by rubbing the polyimide film is formed.

On the other hand, on the surface of the counter substrate 20, a black matrix made of a metal material such as chromium or resin black or a black mask is formed on a region corresponding to a boundary region between pixels of the active matrix substrate 30. Light-shielding film 6 and image display area 7
A light-shielding film 55 that cuts off is formed, and a transparent counter electrode 32 is formed so as to cover these light-shielding films 6 and 55. On the surface of the counter electrode 32, an alignment film 47 formed by rubbing a polyimide film is formed.

[Method of Manufacturing Electro-Optical Panel 1] A method of manufacturing the electro-optical panel 1 thus configured will be described.

(Semiconductor Process) First, an active matrix substrate 30 and a counter substrate 20 are formed using a well-known semiconductor process, as shown in FIG. Also,
As the polarizing plate 11 to be attached to the active matrix substrate 30, a large-sized polarizing plate cut out to a predetermined size is used, so this large-sized polarizing plate is prepared.

(Rubbing Step) Next, as shown in FIG. 5A, the active matrix substrate 30 is arranged on the stage 601 of the rubbing device. Here, at the four corners of the active matrix substrate 30, alignment marks 38A, 38B, 38C, 38D for assembling for aligning the substrates when bonding the active matrix substrate 30 and the counter substrate 20 are formed. Therefore, for example, the two alignment marks 38 for assembly formed on the side of the side on which the rubbing process is started.
B and 38C are observed by a camera or the like, and the position and orientation of the active matrix substrate 30 are adjusted with reference to these alignment marks 38B and 38C. Here, alignment marks 38B and 38C for assembly are used.
Is composed of a thin film formed in a process of forming a TFT or the like on the active matrix substrate 30 using a semiconductor process, and is formed at a position having high positional accuracy for each pixel.

After arranging the active matrix substrate 30 at a predetermined position and orientation in this manner, a predetermined direction (in the example shown here, a direction perpendicular to the straight line L1 connecting the alignment marks 38B and 38C for assembly). The rubbing treatment is performed on the active matrix substrate 30 by moving the roller around which the rubbing cloth 602 is wound.

Here, a pair of markers 603 are formed which move integrally with the rubbing cloth 602 at a position which forms a predetermined positional relationship with the rubbing cloth 602, and these markers 603 are linked with the rubbing processing. As shown in FIG. 5B, rubbing marks 380A, 380A, 3B, 3C, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D
80B, 380C, and 380D are put, for example, near the alignment marks 38A, 38B, 38C, and 38D for assembly.

After the rubbing process is completed in this way, for example, a straight line L2 (or rubbing marks 380B, 380B) connecting the rubbing marks 380A, 380B is obtained.
It is inspected whether a straight line L2 connecting C and a straight line L1 connecting the alignment marks 38B and 38C for assembly are at right angles. Here, the rubbing marks 380A, 380
A straight line L2 connecting B and a ligament mark 3 for assembly
If the straight line L1 connecting 8B and 38C is at a right angle, it can be determined that the rubbing process has been performed in the correct direction.

On the other hand, a rubbing process is also performed on the opposing substrate 20, but the rubbing method is the same as that for the active matrix substrate 30, and a description thereof will be omitted.
However, as described with reference to FIG. 10, the liquid crystal is turned 90 ° between the active matrix substrate 30 and the opposing substrate 20.
The rubbing direction with respect to these substrates is set in a direction orthogonal to the torsional orientation.

As described above, in this embodiment, the orientation of the active matrix substrate 30 is adjusted with reference to the alignment marks 38B and 38C for assembly previously attached to the active matrix substrate 30, and the alignment marks 38B and 38C for assembly are used. Since the rubbing direction is adjusted based on the rubbing direction, the rubbing process can be performed in a predetermined direction. Therefore, from the large substrate to the active matrix substrate 3
Even when the substrate side is inclined when 0 is cut out, the rubbing process can be performed on the active matrix substrate 30 in the direction corresponding to the arrangement direction of the pixels actually formed.

Also, an alignment mark 3 for assembly
Since the rubbing direction is adjusted based on 8B and 38C, when the active matrix substrate 30 and the counter substrate 20 are bonded later, the bonded direction matches the rubbing direction.

Further, the rubbing marks 380A, 380
B, 380C and 380D indicate the actual rubbing direction since they are added in conjunction with the rubbing process. Therefore, it is possible to determine whether or not the rubbing process has been performed in an accurate direction only by checking the positions where the rubbing marks 380A, 380B, 380C, and 380D are added. After completion, defective products and defects due to the deviation of the rubbing direction do not occur.

(Another Rubbing Step) Here, FIG.
As shown in the figure, the active matrix substrate 30 has alignment marks 39A, 39B, 39C, 39 for aligning the polarizing plate, which indicate the position of the polarizing plate 11 to be attached thereto.
D may be formed. In such a case,
For example, alignment marks 39B and 3 for positioning the polarizing plate formed on the side of the side where the rubbing process is started.
The rubbing direction may be adjusted based on 9C. That is, the alignment mark 39 for polarizing plate alignment
B and 39C are observed with a camera or the like, and the position and orientation of the active matrix substrate 30 are adjusted with reference to these alignment marks 39B and 39C. Here, alignment marks 39B for polarizing plate alignment,
39C also includes a thin film formed in a process of forming a TFT or the like on the active matrix substrate 30 using a semiconductor process, and is formed at a position having high positional accuracy for each pixel.

After arranging the active matrix substrate 30 in a predetermined position and orientation in this manner, in a predetermined direction (in the example shown here, a straight line L11 connecting the alignment marks 39B and 39C for aligning the polarizing plate). The roller around which the rubbing cloth 602 is wound is moved in the direction (perpendicular direction) to perform rubbing on the active matrix substrate 30.

Also in this case, the direction in which the rubbing process is actually performed on the active matrix substrate 30 (the rubbing direction) is performed by the pair of markers 603 in conjunction with the rubbing process, as shown in FIG. Rubbing mark 380A, 380 indicating the direction in which cloth 602 actually moved)
B, 380C, 380D, for example, alignment marks 39A, 39B, 39C, 39 for polarizing plate alignment.
It will be attached to D.

After the rubbing process is completed in this manner, for example, a straight line L2 (or rubbing marks 380D, 380B) connecting the rubbing marks 380A, 380B is obtained.
It is checked whether a straight line L2 connecting C and a straight line L11 connecting alignment marks 39B and 39C for aligning the polarizing plate are at right angles. Here, the rubbing mark 380
If the straight line L2 connecting A and 380B and the straight line L11 connecting the alignment marks 39B and 39C for aligning the polarizing plate are at right angles, it can be determined that the rubbing process has been performed in the correct direction. .

As described above, in the present embodiment, the rubbing process is performed after the orientation of the active matrix substrate 30 is adjusted with reference to the alignment marks 39B and 39C for aligning the polarizing plate previously attached to the active matrix substrate 30. Therefore, the rubbing process can be performed in a predetermined direction. Therefore, even if the active matrix substrate 30 is cut out from the large-sized substrate, even if the substrate side is cut out in an inclined state, the active matrix substrate 30 is cut in the direction corresponding to the arrangement direction of the pixels actually formed on the active matrix substrate 30. A rubbing process can be performed.

Since the rubbing direction is adjusted based on the alignment marks 39B and 39C for aligning the polarizing plate, when the polarizing plate 11 is pasted on the electro-optical panel 1, the direction of the polarizing plate 11 and the rubbing direction are changed. Matches.

Further, rubbing marks 380A, 380
B, 380C and 380D indicate the actual rubbing direction since they are added in conjunction with the rubbing process. Therefore, the rubbing marks 380A, 380B, 380C, 380
It is possible to determine whether or not the rubbing process has been performed in an accurate direction only by confirming the position where D is added, and therefore, it is caused by the deviation of the rubbing direction after the electro-optical panel 1 is completed. No defective products or defects occur.

(Substrate Bonding Step) The active matrix substrate 30 and the opposing substrate 20 that have been subjected to the rubbing step in this manner are bonded together with a predetermined gap by a sealing material 52 as shown in FIG. At this time, the active matrix substrate 30 and the opposing substrate 20 are positioned at predetermined positions using the alignment marks 38A, 38B, 38C, and 38D for assembly formed on the active matrix substrate 30 and the opposing substrate 20, respectively.
In addition, it is set in a predetermined direction.

When the substrates are aligned using the alignment marks 38A, 38B, 38C, and 38D for assembly as a mark in this manner, the alignment is performed based on the outer shapes of the active matrix substrate 30 and the counter substrate 20. As compared with the method, the active matrix substrate 30 and the counter substrate 20 can be bonded with high accuracy.

In the rubbing step, the rubbing direction is adjusted based on the alignment marks 38B and 38C for assembly, so that the active matrix substrate 30 and the opposing substrate 20 can be bonded together in the rubbing direction. Therefore, when the liquid crystal is sealed between these substrates (filling step), the liquid crystal can be oriented in a predetermined twist as described with reference to FIGS. 10A and 10B.

(Another Substrate Bonding Step) Also, alignment marks 38A, 38B, 38C, 3
Instead of 8D, the active matrix substrate 30 and the opposing substrate 20 may be aligned and bonded based on the rubbing marks 380A, 380B, 380C, 380D provided as shown in FIG. 5B. When the substrates are bonded in this way, even if the rubbing direction actually performed is shifted, the substrates are bonded based on the direction in which the rubbing process was actually performed, so that the rubbing direction is shifted between the substrates. There is no. Therefore, when the liquid crystal is sealed between these substrates (filling step), FIG.
As described with reference to (B), the liquid crystal can be oriented in a predetermined twist.

(Polarizing Plate Splitting Step) Next, a polarizing plate 11 (see FIG. 4) to be attached to the active matrix substrate 30 is prepared. First, as shown in FIG. 7A, a large polarizing plate 111 capable of taking many polarizing plates 11 is arranged on a stage (not shown) of a cutting device. In addition, above the large polarizing plate 111, a reference polarizing plate 112 having a known direction of the transmission polarization axis is placed above the large polarizing plate 111.
11 is arranged in parallel. Here, the direction of the reference polarizing plate 112 is adjusted so that the transmission polarization axis thereof is aligned with the direction of the punching die of the cutting device.

Next, light is irradiated from a position below the large polarizing plate 111, and the large polarizing plate 111 and the reference polarizing plate 11 are illuminated.
Observe the intensity of light passing through 2. Here, FIG.
As shown in (A), if the transmission polarization axis of the large polarizing plate 111 and the transmission polarization axis of the reference polarizing plate 112 are in the same direction, the light passes through the large polarizing plate 111 and the reference polarizing plate 112. The intensity of the coming light is maximum. On the other hand, the direction of the transmission polarization axis of the large polarizing plate 111 is changed to the reference polarizing plate 11.
2, the large polarizing plate 111 and the reference polarizing plate 11
The intensity of the light passing through 2 decreases.

That is, as shown in FIG. 7B, when the transmission polarization axis of the large polarizing plate 111 is shifted by about 45 ° with respect to the transmission polarization axis of the reference polarizing plate 112, the large polarizing plate 111 In addition, the intensity of light transmitted through the reference polarizing plate 112 is reduced, and the transmission polarization axis of the large polarizing plate 111 is shifted with respect to the transmission polarization axis of the reference polarizing plate 112, as shown in FIG. In a state of being shifted by about 90 °, the intensity of light transmitted through the large polarizing plate 111 and the reference polarizing plate 112 is minimized.

Therefore, while monitoring the intensity of light transmitted through the large polarizing plate 111 and the reference polarizing plate 112, the direction of the large polarizing plate 111 on the stage is changed, and the large polarizing plate 111 and the reference polarizing plate 112 are changed. If the intensity of the light transmitted through the polarizing plate 112 is maximized, FIG.
As shown in (B), regardless of which direction the large polarizing plate 111 faces in shape, the large polarizing plate 111
Are oriented in a predetermined direction (the direction of the transmission polarization axis of the reference polarizer 112). Therefore, after adjusting the orientation of the large polarizing plate 111 in this way, FIG.
(B), if the large polarizing plate 111 is cut along the solid line L30, the polarizing plate 11 is cut out based on the direction of the actual transmission polarization axis of the large polarizing plate 111. It is oriented in a predetermined direction such that the transmission polarization axis is always parallel or perpendicular to that side.

(Polarizing Plate Attaching Step) The polarizing plate 11 cut out in this manner is oriented in a predetermined direction such that the transmission polarization axis is always parallel or perpendicular to its side. ) And (B), the polarizing plate 1 is provided on the active matrix substrate 30 (the electro-optical panel 1).
When attaching 1, as shown in FIG. 9, the sides and corners of the polarizing plate 11 are aligned with the alignment marks 38 A, 38 B, 3
8C, 38D (see FIG. 5), and then glue.

As described above, the polarizing plate 1 is set based on the alignment marks 38A, 38B, 38C, 38D for assembly.
When the polarizing plate 11 is attached, the position and the orientation of the polarizing plate 11 are different from those of the method of aligning the polarizing plate 11 based on the outer shape such as the side or corner of the active matrix substrate 30. Is not affected by the accuracy of Therefore, the position and orientation of the polarizing plate 11 with respect to the active matrix substrate 30 (electro-optical panel 1) can be adjusted with high accuracy.

Further, in the present embodiment, as described with reference to FIG.
Since the rubbing direction is adjusted with reference to B and 38C, the direction of the transmission polarization axis of the polarizing plate 11 can be adjusted to the rubbing direction to the active matrix substrate 30.

(Another Polarizing Plate Sticking Step) FIG.
When attaching the polarizing plate 11 to the active matrix substrate 30 (electro-optical panel 1) described with reference to (A) and (B), as shown in FIG. Alignment marks 39A, 39B, 39 for positioning the polarizing plate formed on the matrix substrate 30
C, 39D (see FIG. 6), and then glue.

As described above, when the polarizing plate 11 is stuck on the basis of the alignment marks 39A, 39B, 39C and 39D for aligning the polarizing plate, the active matrix substrate 3
Polarizing plate 1 based on the external shape such as the side or corner of 0
Compared with the method of aligning 1, the position and the orientation of the polarizing plate 11 are not affected by the accuracy of the outer shape of the active matrix substrate 30. Therefore, the position and orientation of the polarizing plate 11 with respect to the active matrix substrate 30 (electro-optical panel 1) can be adjusted with high accuracy.

In the present embodiment, as described with reference to FIG. 6A, the lambing direction is adjusted with reference to the alignment marks 39B and 39C for aligning the polarizing plate. The direction of the axis can be matched with the rubbing direction to the active matrix substrate 30.

(Still Another Polarizing Plate Adhering Step)
(B) or the active matrix substrate 30 (electro-optical panel 1) described with reference to FIG.
As shown in FIG. 9, when affixing is performed, instead of alignment marks 38A, 38B, 38C, and 38D for assembly (see FIG. 5) and alignment marks 39A, 39B, 39C, and 39D for aligning the polarizing plate, as shown in FIG. When the polarizing plate 11 is attached based on the rubbing marks 380A, 380B, 380C, and 380D that are provided in conjunction with the rubbing process in the rubbing process, the active matrix substrate 3
Polarizing plate 1 based on the external shape such as the side or corner of 0
Compared with the method of aligning 1, the position and the orientation of the polarizing plate 11 are not affected by the accuracy of the outer shape of the active matrix substrate 30. Therefore, the position and orientation of the polarizing plate 11 with respect to the active matrix substrate 30 (electro-optical panel 1) can be adjusted with high accuracy.

In this embodiment, since the direction and position of the polarizing plate 11 are determined in accordance with the rubbing direction actually performed, the orientation matching the direction of the rubbing process actually performed on the active matrix substrate 30 is performed. The substrates can be bonded together.

When aligning the orientation of the polarizing plate 11 with the electro-optical panel 1, the rubbing marks 380 A, 380 A, 3 B
When the sides and angles of the polarizing plate 11 are aligned with 80B, 380C and 380D (see FIG. 8), the direction of the transmission polarization axis of the polarizing plate 11 in the rubbing direction (orientation direction of the electro-optical material) can be adjusted with high accuracy. Can be matched.

Further, the alignment mark for assembling and the alignment mark for attaching the polarizing plate are simultaneously formed at a predetermined interval from the same material, and in the rubbing process, the alignment mark for assembling and the polarizing plate are attached. After aligning the substrate in a predetermined direction with reference to at least one of the alignment marks, a rubbing process may be performed. According to this configuration, since the alignment mark for assembling and the alignment mark for attaching the polarizing plate are formed simultaneously with the same material, there is no displacement or inclination between the two marks. In addition, rubbing can be performed with high accuracy even if rubbing is performed using either mark as a reference, and the rubbing direction, the bonding between the substrates, and the bonding of the polarizing plate to the substrate can be performed with high accuracy.

[0071]

As described above, in the electro-optical device and the method of manufacturing the same according to the present invention, since the transmission polarization axis of the polarizing plate is oriented in a predetermined direction on the electro-optical panel, the contrast ratio can be improved. In addition, the display quality can be improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a projection display device (electro-optical device) showing an example of use of an electro-optical panel.

FIG. 2 is a plan view of the electro-optical panel viewed from a counter substrate side.

FIG. 3 is a cross-sectional view of the electro-optical panel taken along line HH ′ in FIG.

FIG. 4 is an enlarged cross-sectional view of the electro-optical panel, illustrating a bonding structure of an active matrix substrate and a counter substrate used in the electro-optical panel to which the present invention is applied.

FIGS. 5A and 5B are explanatory views showing a rubbing step for a substrate in a method of manufacturing an electro-optical device to which the present invention is applied.

FIGS. 6A and 6B are explanatory views showing another rubbing step for a substrate in a method of manufacturing an electro-optical device to which the present invention is applied.

FIGS. 7A to 7C are diagrams for explaining a method of manufacturing an electro-optical device to which the present invention is applied, in which a polarizing plate is arranged in a predetermined direction in a polarizing plate dividing step of dividing a large polarizing plate. FIG. 4 is an explanatory diagram showing the method.

8 (A) and 8 (B) are explanatory views showing how a large polarizing plate oriented in the manner shown in FIG. 7 is divided.

FIG. 9 is an explanatory diagram showing a polarizing plate attaching step of attaching a polarizing plate to an electro-optical panel in a method of manufacturing an electro-optical device to which the present invention is applied.

FIGS. 10A and 10B are explanatory diagrams showing the configuration and operation of an electro-optical panel in a normally white mode.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 electro-optical panel 6 light-shielding film on counter substrate side 7 screen display area 8 pixel electrode 10 TFT for pixel switching 11, 12 polarizing member 20 counter substrate 30 active matrix substrate 32 counter electrode 38 A, 38 B, 38 C, 38 D Assembly alignment Mark 39A, 39B, 39C, 39D Alignment mark for polarizing plate alignment 39 Liquid crystal (electro-optical material) 46, 47 Alignment film 380A, 380B, 380C, 380D Rubbing mark 2001 Projection display device (electro-optical device) 2011 Light source lamp (light source)

Continued on the front page F term (reference) 2H088 EA14 EA15 FA03 FA10 FA16 HA03 HA08 HA13 HA14 HA17 HA18 HA21 HA24 HA28 JA05 JA13 KA17 MA02 MA18 2H090 HB08Y HD14 KA05 KA08 LA03 LA04 LA08 LA09 LA12 LA15 LA16 LA20 MB01

Claims (9)

[Claims] A rubbing process in which a thin film formed on the surface of a pair of substrates for sandwiching an electro-optical material is rubbed in a predetermined direction to make the thin film an alignment film; A substrate bonding step of bonding the pair of substrates so that the alignment films face each other with a predetermined gap therebetween, and filling an electro-optical material between the pair of substrates bonded in the substrate bonding step. A method of manufacturing an electro-optical device having a filling step, wherein in the rubbing step, the substrate is aligned in a predetermined direction based on a mark previously attached to the substrate, and then a rubbing process is performed. A method for manufacturing an electro-optical device. 2. The electro-optical device according to claim 1, wherein in the substrate bonding step, the pair of substrates is bonded in a predetermined direction based on the mark, and then the pair of substrates is bonded. Manufacturing method. 3. The method according to claim 1, further comprising the step of attaching a polarizing plate to at least one substrate surface of the pair of substrates, wherein the attaching the polarizing plate is performed based on the mark. A method of manufacturing an electro-optical device, comprising: aligning the substrate in a predetermined direction; and bonding the polarizing plate to the substrate. 4. A rubbing process in which a rubbing process in a predetermined direction is performed on a thin film formed on a surface of a pair of substrates for sandwiching an electro-optical material to make the thin film an alignment film; A substrate bonding step of bonding the pair of substrates so that the alignment films face each other with a predetermined gap therebetween, wherein the electro-optical material is applied between the pair of substrates bonded in the substrate bonding step. A method for manufacturing an electro-optical device having a filling step of filling a first mark for assembling on the substrate and a second mark for attaching a polarizing plate to the substrate.
In the step of simultaneously forming marks with the same material at predetermined intervals, and in the rubbing step, the first and second marks are formed.
A method for manufacturing an electro-optical device, comprising: performing a rubbing process after aligning a substrate in a predetermined direction with reference to at least one of the marks. 5. A rubbing process in which a rubbing process in a predetermined direction is performed on a thin film formed on a surface of a pair of substrates for sandwiching an electro-optical material to make the thin film an alignment film; A substrate bonding step of bonding the pair of substrates so that the alignment films face each other with a predetermined gap therebetween, and filling an electro-optical material between the pair of substrates bonded in the substrate bonding step. A method of manufacturing an electro-optical device, comprising: filling a rubbing mark indicating a rubbing direction on the substrate in conjunction with the rubbing operation in the rubbing step. Method. 6. The method for manufacturing an electro-optical device according to claim 5, wherein an inspection is performed as to whether or not rubbing processing has been normally performed using the rubbing mark. 7. The method for manufacturing an electro-optical device according to claim 5, wherein in the substrate bonding step, the pair of substrates are bonded to each other with the rubbing mark as a reference. 8. The method according to claim 5, further comprising: attaching a polarizing plate to at least one of the pair of substrates, wherein the attaching the polarizing plate includes: A method of manufacturing an electro-optical device, comprising: after positioning a polarizing plate with respect to at least one of the pair of substrates based on the rubbing mark, bonding the substrate and the polarizing plate. 9. The method according to claim 1, wherein
A light source, a condensing optical system for guiding light emitted from the light source to the electro-optical panel, and an enlarged projection optical system for enlarging and projecting light modulated by the electro-optical panel are arranged on the optical axis of the device. A method for manufacturing an electro-optical device.