JP2012123144A - Liquid crystal device, method for manufacturing liquid crystal device, and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal device in which uneven distribution of ionic impurities in a liquid crystal is suppressed and excellent display quality can be obtained, a method for manufacturing the liquid crystal device, and an electronic equipment having the liquid crystal device.SOLUTION: The liquid crystal device includes a liquid crystal layer having negative dielectric anisotropy held between a pair of substrates, and a display region E1 including a plurality of pixels. The liquid crystal device also includes: a first alignment layer formed on each of sides facing the liquid crystal layer of the pair of substrates in the display region E1, and subjected to substantially vertical alignment treatment in a first orientation direction θa; and a second alignment layer formed on each of the sides facing the liquid crystal layer of the pair of substrates in at least a part of a peripheral region E2 enclosing the display region E1, and subjected to a substantially vertical alignment treatment in a second orientation direction θd intersecting with the first orientation direction θa.

Description

  The present invention relates to a liquid crystal device, a method for manufacturing a liquid crystal device, and an electronic apparatus.

  A liquid crystal device generally has a structure in which liquid crystal is injected and sealed between a pair of substrates subjected to an alignment treatment. In the manufacturing process of such a liquid crystal device, it is known that, for example, when ionic impurities are mixed during liquid crystal injection or are eluted from a sealing material surrounding the liquid crystal layer, they diffuse and aggregate in the display area, resulting in deterioration of display characteristics. ing.

  For the purpose of suppressing degradation of display characteristics caused by such ionic impurities, for example, Patent Document 1 discloses that, out of a pair of substrates, one substrate is a pixel electrode formed in the pixel region, and the pixel region. A peripheral electrode formed in the peripheral region, and the other substrate includes a pixel electrode portion formed in the pixel region and a peripheral electrode formed in the peripheral region, and at least one peripheral electrode is adjacent There is disclosed a liquid crystal display device that includes a plurality of electrodes and that has different drive voltage values applied between adjacent electrodes of the peripheral electrode.

  According to the liquid crystal display device of Patent Document 1, by changing the potential between adjacent electrodes of the peripheral electrode, a lateral electric field is generated between the electrodes, in addition to the flow caused by minute fluctuations of the liquid crystal, The ionic impurities in the pixel region can be moved to the outside of the pixel region, and display defects such as image sticking caused by the ionic impurities can be prevented.

Further, Patent Document 2 discloses a liquid crystal display in which the minimum voltage applied to the liquid crystal layer is 1.2 V or more in order to display an image on a display unit including a plurality of display pixels arranged in a matrix. An apparatus is disclosed.
According to the liquid crystal display device of Patent Document 2, it is possible to prevent image sticking from occurring in the vicinity of the boundary between the portion where the flow of ionic impurities is present and the portion where it does not exist by defining the minimum voltage. Yes. That is, the retention of ionic impurities in the liquid crystal can be prevented.

JP 2008-58497 A JP 2010-113148 A

  The liquid crystal display device of Patent Document 1 or Patent Document 2 described above requires electronic components such as a dedicated drive IC corresponding to the electro-optical characteristics of the liquid crystal used, and requires adjustment of the drive voltage (drive waveform). There is a problem that the manufacturing cost may increase and the productivity may decrease.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A liquid crystal device according to this application example is a liquid crystal device having a liquid crystal layer having negative dielectric anisotropy sandwiched between a pair of substrates and a display region including a plurality of pixels. A first alignment film provided on each side of the pair of substrates facing the liquid crystal layer in the region and subjected to a substantially vertical alignment process in a first azimuth angle direction; and at least a peripheral region surrounding the display region A second alignment film provided on each side of the pair of substrates facing the liquid crystal layer and subjected to a substantially vertical alignment process in a second azimuth angle direction intersecting the first azimuth angle direction; It is characterized by providing.

  According to this configuration, the ionic impurities contained in the liquid crystal move along the first azimuth direction in the display region, but move in the second azimuth direction intersecting the first azimuth direction in the peripheral region. Therefore, it can suppress that an ionic impurity is unevenly distributed in a 1st azimuth angle direction. Therefore, it is possible to provide a liquid crystal device in which display defects such as image sticking due to uneven distribution of ionic impurities are reduced.

Application Example 2 In the liquid crystal device according to the application example, the first alignment film is an inorganic alignment film in which a column is inclined in the first azimuth angle direction, and the second alignment film is the second azimuth angle direction. It is an inorganic alignment film in which the column is inclined.
According to this, since the inorganic alignment film is more likely to cause display defects due to uneven distribution of ionic impurities than the organic alignment film, it is particularly effective to be applied to a liquid crystal device including the inorganic alignment film.

Application Example 3 In the liquid crystal device according to the application example, the display area may be a quadrangle when seen in a plan view, and the first azimuth angle direction may be a direction that obliquely intersects a side portion of the display area. Good.
According to this, the ionic impurities in the liquid crystal move toward the corner portion in the first azimuth angle direction in the display region, but thereafter, the second azimuth intersecting the first azimuth angle direction in the peripheral region of the corner portion. Move in the angular direction. That is, it is possible to reduce uneven distribution of ionic impurities at the corners in the first azimuth angle direction of the display region.

Application Example 4 In the liquid crystal device according to the application example described above, the first azimuth angle direction intersects the side of the display area at an angle of approximately 45 degrees, and the second azimuth angle direction corresponds to the display area. It is preferable that the first azimuth angle direction intersects at an angle that is not parallel to the side of the first azimuth.
When the second azimuth angle direction is parallel to the side of the display area, the ionic impurities that have moved to the peripheral area tend to concentrate on the corner of the peripheral area. There is a risk of reaching the corners. According to this, since the second azimuth angle direction intersects the first azimuth angle direction at an angle that is not parallel to the side portion of the display area, the ionic impurities are in the first azimuth direction of the display area. The uneven distribution at the corners can be further reduced.

Application Example 5 In the liquid crystal device according to the application example, the second alignment film is provided in a portion of the peripheral region along a corner of the display region in the first azimuth direction, and the display region The first alignment film is provided in a portion of the peripheral region along the other corner.
According to this, uneven distribution of ionic impurities at each corner of the display region can be further reduced.

Application Example 6 In the liquid crystal device according to the application example described above, drivable dummy pixels are provided in the peripheral region.
According to this, the flow of the first azimuth direction is caused by the change in the orientation of the liquid crystal molecules in the first azimuth direction as the pixel is electrically driven, and the ionic impurities in the liquid crystal follow the flow. Move. Therefore, by providing dummy pixels that can be driven in the peripheral region, ionic impurities carried to the peripheral region can be positively moved in the second azimuth direction. That is, uneven distribution of ionic impurities can be more efficiently suppressed.

  Application Example 7 A method for manufacturing a liquid crystal device according to this application example includes a liquid crystal layer having negative dielectric anisotropy sandwiched between a pair of substrates and a display region including a plurality of pixels. In each of the pair of substrates, a first alignment film forming step of forming a first alignment film in which a substantially vertical alignment process is performed on the display region in a first azimuth angle direction, and a periphery surrounding the display region And a second alignment film forming step of forming a second alignment film in which at least a part of the region is subjected to the substantially vertical alignment treatment in a second azimuth angle direction intersecting the first azimuth angle direction. And

  According to this method, although the first alignment film in the display region and the second alignment film in the peripheral region are both subjected to the substantially vertical alignment treatment, the azimuth angle direction is different, so that the ions contained in the liquid crystal Although the ionic impurities move along the first azimuth direction in the display region, they move in the second azimuth direction intersecting the first azimuth direction in the peripheral region. Therefore, uneven distribution of ionic impurities in the first azimuth angle direction is suppressed, and a liquid crystal device in which display defects such as image sticking due to uneven distribution of ionic impurities is reduced can be manufactured.

Application Example 8 In the method of manufacturing a liquid crystal device according to the application example, in the first alignment film forming step, the inorganic first alignment film in which a column is inclined in the first azimuth angle direction is formed, and the second alignment film is formed. In the alignment film forming step, the inorganic second alignment film having a column inclined in the second azimuth angle direction is formed.
According to this method, the inorganic alignment film is more likely to cause a display defect due to uneven distribution of ionic impurities than the organic alignment film, and is therefore applied to a method of manufacturing a liquid crystal device including an inorganic alignment film forming step. This is particularly effective.

Application Example 9 In the method for manufacturing a liquid crystal device according to the application example described above, it is preferable that the first alignment film formation step is performed after the second alignment film formation step.
According to this method, compared with the case where the second alignment film is formed after the first alignment film is formed in the display region, the problem that the second alignment film wraps around the display region later is prevented. A stable orientation state in the display area can be ensured.

Application Example 10 An electronic apparatus according to this application example includes the liquid crystal device according to the application example described above.
According to this configuration, display defects due to uneven distribution of ionic impurities are reduced, and an electronic device having excellent display quality can be provided.

(A) is a schematic plan view which shows the structure of a liquid crystal device, (b) is a schematic sectional drawing cut | disconnected by the H-H 'line | wire of (a). FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device. (A) is a schematic sectional drawing which shows the formation state of the inorganic alignment film in a liquid crystal device, and the orientation state of a liquid crystal molecule, (b) is the schematic which shows the behavior of a liquid crystal molecule. (A) is a schematic plan view which shows the relationship between a display area and a peripheral area, (b) is a principal part enlarged plan view which shows an example of arrangement | positioning of the dummy pixel in a peripheral area. The schematic plan view which shows the relationship between the azimuth angle direction and display nonuniformity in a substantially vertical alignment process. 6 is a flowchart showing a method for manufacturing a liquid crystal device. The schematic plan view which shows the azimuth angle direction in a substantially vertical alignment process. Schematic which shows the structure of the projection type display apparatus as an electronic device. The schematic plan view which shows the method of the substantially vertical alignment process of a modification.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that the drawings to be used are appropriately enlarged or reduced so that the part to be described can be recognized.

  In the following embodiments, when “on the substrate” is described, the substrate is disposed so as to be in contact with the substrate, or is disposed on the substrate via another component, or the substrate. It is assumed that a part is arranged so as to be in contact with the upper part and a part is arranged via another component.

  In the present embodiment, an active matrix liquid crystal device including a thin film transistor (TFT) as a pixel switching element will be described as an example. This liquid crystal device can be suitably used as, for example, a light modulation element (liquid crystal light valve) of a projection type display device (liquid crystal projector) described later.

<Liquid crystal device>
First, the liquid crystal device of this embodiment will be described with reference to FIGS. 1A is a schematic plan view showing the configuration of the liquid crystal device, FIG. 1B is a schematic cross-sectional view taken along line HH ′ of FIG. 1A, and FIG. 2 is an electrical configuration of the liquid crystal device. FIG.

  As shown in FIGS. 1A and 1B, a liquid crystal device 100 according to the present embodiment includes an element substrate 10 and a counter substrate 20 that are disposed to face each other, and a liquid crystal layer 50 that is sandwiched between the pair of substrates. . As the element substrate 10 and the counter substrate 20, a transparent glass substrate such as quartz is used.

  The element substrate 10 is slightly larger than the counter substrate 20, and both substrates are bonded via a sealing material 40 arranged in a frame shape, and liquid crystal is sealed in the gap to form a liquid crystal layer 50. For the sealing material 40, for example, an adhesive such as a thermosetting or ultraviolet curable epoxy resin is employed. A spacer (not shown) is mixed in the sealing material 40 to keep the distance between the pair of substrates constant.

  A light shielding film 21 is similarly provided in a frame shape inside the sealing material 40 arranged in a frame shape. The light shielding film 21 is made of, for example, a light shielding metal or metal oxide, and the inside of the light shielding film 21 is a pixel region E having a plurality of pixels P. Although not shown in FIG. 1, the pixel region E is also provided with a light-shielding portion that divides a plurality of pixels P in a plane.

A data line driving circuit 101 is provided between the element substrate 10 and the sealing material 40 along one side. Further, an inspection circuit 103 is provided inside the sealing material 40 along the other one side facing the one side. Further, a scanning line driving circuit 102 is provided inside the sealing material 40 along the other two sides orthogonal to the one side and facing each other. A plurality of wirings 105 that connect the two scanning line driving circuits 102 are provided inside the sealing material 40 on the other side facing the one side. Wirings connected to the data line driving circuit 101 and the scanning line driving circuit 102 are connected to a plurality of external connection terminals 104 arranged along the one side.
Hereinafter, the direction along the one side will be referred to as the X direction, and the direction along the other two sides orthogonal to the one side and facing each other will be described as the Y direction.

As shown in FIG. 1B, on the surface of the element substrate 10 on the liquid crystal layer 50 side, a light-transmitting pixel electrode 15 provided for each pixel P and a thin film transistor (TFT; Thin Film) as a switching element. Transistor) 30, signal wiring, and an alignment film 18 covering these are formed.
Further, a light shielding structure is employed that prevents light from entering the semiconductor layer in the TFT 30 and causing a light leakage current to flow, resulting in an inappropriate switching operation.

  On the surface of the counter substrate 20 on the liquid crystal layer 50 side, a light shielding film 21, an interlayer film layer 22 formed so as to cover the light shielding film 21, and a common electrode 23 provided so as to cover the interlayer film layer 22 are shared. An alignment film 24 covering the electrode 23 is provided.

  As shown in FIG. 1A, the light shielding film 21 is provided in a frame shape at a position where the data line driving circuit 101, the scanning line driving circuit 102, and the inspection circuit 103 overlap in plan view. Thus, the light incident from the counter substrate 20 side is shielded, and the malfunction of the peripheral circuits including these drive circuits due to the light is prevented. Further, unnecessary stray light is shielded from entering the pixel region E to ensure high contrast in the display of the pixel region E.

  The interlayer film layer 22 is made of an inorganic material such as silicon oxide, for example, and is provided so as to cover the light shielding film 21 with light transmittance. Examples of a method for forming such an interlayer film layer 22 include a method of forming a film using a plasma CVD method or the like.

  The common electrode 23 is made of, for example, a transparent conductive film such as ITO, and covers the interlayer film layer 22 and, as shown in FIG. 1A, the element substrate 10 side by the vertical conduction parts 106 provided at the four corners of the counter substrate 20. It is electrically connected to the wiring.

  The alignment film 18 covering the pixel electrode 15 and the alignment film 24 covering the common electrode 23 are selected based on the optical design of the liquid crystal device 100. In the present embodiment, the liquid crystal molecules having negative dielectric anisotropy are applied so as to be substantially vertically aligned with a pretilt angle with respect to the alignment film surface, such as SiOx (silicon oxide). An inorganic alignment film formed by using a physical vapor deposition method is used. Examples of the physical vapor deposition method include a vacuum vapor deposition method and a vacuum sputtering method in which an inorganic material is vaporized in a vacuum and reaches a film-forming object to form a film. The method for forming the inorganic alignment film and the detailed alignment state of the liquid crystal molecules will be described later.

  In the present embodiment, the pixel area E includes a display area where effective display is performed and a peripheral area surrounding the display area. Furthermore, the azimuth angle direction of the substantially vertical alignment process is different between the display area and the peripheral area. A method of forming such alignment films 18 and 24 will be described later.

As shown in FIG. 2, the liquid crystal device 100 is disposed so as to be parallel to the plurality of scanning lines 3 a and the plurality of data lines 6 a as signal lines that are insulated and orthogonal to each other at least in the pixel region E along the data lines 6 a. Capacitance line 3b.
The direction in which the scanning line 3a extends is the X direction, and the direction in which the data line 6a extends is the Y direction.

  A pixel electrode 15, a TFT 30, and a storage capacitor 16 are provided in a region divided by the scanning line 3a, the data line 6a, the capacitor line 3b, and these signal lines, and these constitute a pixel circuit of the pixel P. is doing.

The scanning line 3 a is electrically connected to the gate of the TFT 30, and the data line 6 a is electrically connected to the source of the TFT 30. The pixel electrode 15 is electrically connected to the drain of the TFT 30.
The data line 6a is connected to the data line driving circuit 101 (see FIG. 1), and supplies image signals D1, D2,..., Dn supplied from the data line driving circuit 101 to the pixels P. The scanning line 3a is connected to a scanning line driving circuit 102 (see FIG. 1), and supplies scanning signals SC1, SC2,..., SCm supplied from the scanning line driving circuit 102 to each pixel P. The image signals D1 to Dn supplied from the data line driving circuit 101 to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 6a for each group. Good. The scanning line driving circuit 102 supplies the scanning signals SC1 to SCm to the scanning line 3a in a pulse-sequential manner at a predetermined timing.

In the liquid crystal device 100, the TFT 30 that is a switching element is turned on for a certain period by the input of the scanning signals SC1 to SCm, so that the image signals D1 to Dn supplied from the data line 6a are supplied to the pixel electrode 15 at a predetermined timing. It is the structure written in. The predetermined level of image signals D1 to Dn written to the liquid crystal layer 50 via the pixel electrode 15 is held for a certain period between the pixel electrode 15 and the common electrode 23 arranged to face each other via the liquid crystal layer 50. The
In order to prevent the held image signals D1 to Dn from leaking, the holding capacitor 16 is connected in parallel with the liquid crystal capacitor formed between the pixel electrode 15 and the common electrode 23. The storage capacitor 16 is provided between the drain of the TFT 30 and the capacitor line 3b. The capacitor line 3b is connected to a fixed potential. The fixed potential is, for example, a common potential (LCCOM) applied to GND or the common electrode 23.

  Note that a data line 6a is connected to the inspection circuit 103 shown in FIG. 1A, and an operation defect or the like of the liquid crystal device 100 is confirmed by detecting the image signal in the manufacturing process of the liquid crystal device 100. Although it can be configured, it is omitted in the equivalent circuit of FIG. The inspection circuit 103 includes a sampling circuit that samples the image signal and supplies it to the data line 6a, and a precharge circuit that supplies a precharge signal of a predetermined voltage level to the data line 6a prior to the image signal. Also good.

  Such a liquid crystal device 100 is a transmission type, and adopts an optical design of a normally white mode in which the pixel P is brightly displayed when not driven and a normally black mode in which the pixel P is darkly displayed when not driven. Polarizing elements are arranged and used according to the optical design on the light incident side and the light exit side, respectively.

Next, the alignment state of the liquid crystal molecules in the liquid crystal device 100 will be described with reference to FIG. FIG. 3A is a schematic sectional view showing the formation state of the inorganic alignment film and the alignment state of the liquid crystal molecules in the liquid crystal device, and FIG. 3B is a schematic view showing the behavior of the liquid crystal molecules.
As shown in FIG. 3A, the orientation obtained by obliquely depositing silicon oxide on the surfaces of the pixel electrode 15 and the common electrode 23 in the liquid crystal device 100 by vacuum vapor deposition which is an example of physical vapor deposition. A film 18 and an alignment film 24 are formed. Specifically, the angle θb of the vapor deposition direction with respect to the substrate surface facing the liquid crystal layer 50 is approximately 45 °. By such oblique vapor deposition, silicon oxide crystals grow in a columnar shape on the substrate surface in the vapor deposition direction. These columnar crystals are called columns 18a and 24a. The alignment films 18 and 24 are aggregates of such columns 18a and 24a. Further, the angle θc in the growth direction of the columns 18a and 24a with respect to the substrate surface does not necessarily coincide with the angle θb in the vapor deposition direction, and in this case, is approximately 70 °.

  The pretilt angle θp of the liquid crystal molecules LC that are substantially vertically aligned on the surfaces of the alignment films 18 and 24 is about 85 °. Further, the pretilt direction of the liquid crystal molecules LC viewed from the normal direction of the substrate surface, that is, the azimuth angle direction, is the same as the planar deposition direction of the oblique deposition in the alignment films 18 and 24. The azimuth angle direction of the substantially vertical alignment process is appropriately set based on the optical design conditions of the liquid crystal device 100.

  A device including the element substrate 10 and the counter substrate 20 arranged to face each other and the liquid crystal layer 50 sandwiched between the pair of substrates is referred to as a liquid crystal panel 110. The liquid crystal device 100 is used with polarizing elements 41 and 42 disposed on the light incident side and the light exit side of the liquid crystal panel 110, respectively. Further, the polarizing elements 41 and 42 are such that one transmission axis or absorption axis of the polarizing elements 41 and 42 is parallel to the X direction or the Y direction, and the transmission axes or absorption axes thereof are orthogonal to each other. In this manner, the liquid crystal panel 110 is disposed.

  In the present embodiment, a substantially vertical alignment process is performed in the display region so that the azimuth angle of the pretilt of the liquid crystal molecules LC intersects with the transmission axis or absorption axis of the polarizing elements 41 and 42 at 45 °. Therefore, as shown in FIG. 3B, when the liquid crystal layer 50 is driven by applying a driving voltage between the pixel electrode 15 and the common electrode 23, the liquid crystal molecules LC are tilted in the azimuth direction of the pretilt. An optical arrangement is obtained to obtain transmittance. When driving (ON / OFF) of the liquid crystal layer 50 is repeated, the liquid crystal molecules LC repeatedly behave in the direction of the pretilt azimuth or return to the initial alignment state. Such a substantially vertical alignment treatment in which the behavior of the liquid crystal molecules LC occurs is referred to as a uniaxial substantially vertical alignment treatment.

  In addition, the incident direction of the light with respect to the liquid crystal panel 110 is not limited to entering from the element substrate 10 side, as shown to Fig.3 (a). In addition, an optical compensation element such as a phase difference plate may be provided on the light incident side or the light emitting side.

  FIG. 4A is a schematic plan view showing the relationship between the display area and the peripheral area, and FIG. 4B is an enlarged plan view of a main part showing an example of the arrangement of dummy pixels in the peripheral area.

  As shown in FIG. 4A, the pixel area E in the liquid crystal device 100 includes a display area E1 where effective display is performed and a peripheral area E2 surrounding the display area E1.

  As shown in FIG. 4B, pixels P1 are arranged in a matrix in the display area E1. In the peripheral area E2, three columns of a plurality of dummy pixels P2 are arranged in the X direction so as to surround the display area E1, and three rows of a plurality of dummy pixels P2 are arranged in the Y direction. Both the pixel P1 and the dummy pixel P2 have the electrical configuration of the pixel P described above, and can be driven by a signal given thereto. Note that the number of dummy pixels P2 arranged in the peripheral region E2 is not limited to this.

  FIG. 5 is a schematic plan view showing the relationship between the azimuth angle direction and display unevenness in the substantially vertical alignment process. As shown in FIG. 5, in the display area E1, an azimuth angle θa that makes the azimuth angle direction of the uniaxial substantially vertical alignment process the Y direction is set to 45 °. Specifically, an arrow direction indicated by a broken line is a direction of oblique deposition with respect to the element substrate 10 and is a direction from the upper right to the lower left. On the other hand, the arrow direction indicated by the solid line is the direction of oblique vapor deposition with respect to the counter substrate 20 disposed to face the element substrate 10, and is the direction from the lower left to the upper right (see FIG. 3). Such an azimuth angle direction in the display area E1 may be referred to as a first azimuth angle direction θa using the azimuth angle θa as it is.

According to the first azimuth angle direction θa, the liquid crystal layer 50, that is, the pixel P1 (see FIG. 4B) described above is driven, so that the liquid crystal molecules LC aligned substantially perpendicular to the substrate surface are first. The behavior swung in the azimuth angle direction θa is shown. As a result, the behavior of the liquid crystal molecules LC toward the first azimuth angle direction θa, that is, the flow (flow) occurs, and the ionic impurities contained in the liquid crystal move in the liquid crystal along this flow (flow). It is carried to the corner of the display area E1 located in the first azimuth angle direction θa and uneven distribution of ionic impurities occurs. Then, as shown in FIG. 5, display unevenness such as image sticking and brightness unevenness due to uneven distribution of ionic impurities occurs at the corners of the display region E1.
Note that the first azimuth angle direction θa of 45 ° may be 45 ° to the right as well as 45 ° to the right as shown in FIG. 5. In this case, the upper left and lower right of the display area E1 in FIG. Display unevenness occurs at the corners.

  In the present embodiment, by changing the azimuth angle direction of the substantially vertical alignment process between the display area E1 and the peripheral area E2, the ionic impurities carried to the corner of the display area E1 are changed in the first azimuth angle direction in the peripheral area E2. It is moved in a direction different from θa. Thereby, uneven distribution of ionic impurities at the corners of the display region E1 is suppressed, and display unevenness is reduced. A more specific method of the substantially vertical alignment treatment will be described in the following liquid crystal device manufacturing method.

<Method for manufacturing liquid crystal device>
Next, a method for manufacturing the liquid crystal device 100 of the present embodiment will be described with reference to FIGS. FIG. 6 is a flowchart showing a method for manufacturing a liquid crystal device, and FIG. 7 is a schematic plan view showing an azimuth direction in a substantially vertical alignment process.

  As shown in FIG. 6, the manufacturing method of the liquid crystal device 100 of the present embodiment includes a pixel forming process (step S1), a second alignment film forming process (step S2), and a manufacturing process on the element substrate 10 side. A first alignment film forming step (step S3). In addition, a counter electrode forming process (step S4), a second alignment film forming process (step S5), and a first alignment film forming process (step S6), which show manufacturing processes on the counter substrate 20 side, are provided. Then, a liquid crystal injection / sealing step (step S7) for injecting and sealing liquid crystal between the element substrate 10 and the counter substrate 20 each having an alignment film formed thereon is provided.

  First, in the pixel formation process of step S1, the pixel electrode 15, the TFT 30, and the storage capacitor 16 are arranged in a region partitioned by the scanning line 3a, the data line 6a, the capacitor line 3b, and these signal lines on the element substrate 10. And form. As a method for forming such a pixel circuit, a known method can be employed. Further, such a pixel circuit is formed so as to function as the pixel P1 in the display area E1 and to function as the dummy pixel P2 in the peripheral area E2. That is, the pixel forming process includes a process of forming the dummy pixel P2. Then, the process proceeds to step S2.

  In the second alignment film forming step in step S2, as shown in FIG. 7, a substantially vertical alignment process in the second azimuth angle direction θd is performed on the peripheral region E2 of the element substrate 10. Specifically, silicon oxide is obliquely deposited from the second azimuth angle direction θd intersecting the first azimuth angle direction θa to the peripheral area E2 in a state where the display area E1 of the element substrate 10 is shielded by, for example, a mask. . More specifically, when the substantially vertical alignment processing surface of the element substrate 10 is turned upward, oblique deposition is performed from a 45 ° direction from the lower right to the upper left or a 45 ° direction from the upper left to the lower right in the drawing. . That is, the first azimuth angle direction θa and the second azimuth angle direction θd are orthogonal to each other. As a result, a second alignment film (inorganic alignment film) subjected to the substantially vertical alignment process in the second azimuth angle direction θd is formed in the peripheral region E2 of the element substrate 10. Then, the process proceeds to step S3.

  In the first alignment film forming step of step S3, as shown in FIG. 7, a substantially vertical alignment process in the first azimuth angle direction θa is performed on the display region E1 of the element substrate 10. Specifically, silicon oxide is obliquely evaporated from the first azimuth angle direction θa to the display region E1 in a state where the peripheral region E2 of the element substrate 10 is shielded by, for example, a mask. More specifically, when the substantially vertical alignment processing surface of the element substrate 10 is turned upward, the oblique deposition is performed from a 45 ° direction from the upper right to the lower left in the drawing. As a result, a first alignment film (inorganic alignment film), that is, an alignment film 18 (see FIG. 3A) that has been subjected to a substantially vertical alignment process in the first azimuth angle direction θa is formed in the display region E1 of the element substrate 10. Is done. Then, the process proceeds to step S4.

  In the counter electrode forming step of step S4, the common electrode 23 is formed on the side of the counter substrate 20 facing the liquid crystal layer 50. Specifically, the common electrode 23 is formed by patterning a transparent conductive film such as ITO by sputtering, for example. A known method can be used for forming the light shielding film 21 and the interlayer film layer 22 covering the light shielding film 21. Then, the process proceeds to step S5.

  In the second alignment film forming step of step S5, as in the element substrate 10, as shown in FIG. 7, a substantially vertical alignment process in the second azimuth angle direction θd is performed on the peripheral region E2 of the counter substrate 20. Specifically, silicon oxide is obliquely deposited from the second azimuth angle direction θd intersecting the first azimuth angle direction θa in the peripheral area E2 in a state where the display area E1 of the counter substrate 20 is shielded by, for example, a mask. . More specifically, when the substantially vertical alignment processing surface of the counter substrate 20 is turned down, oblique deposition is performed from a 45 ° direction from the lower right to the upper left or a 45 ° direction from the upper left to the lower right in the drawing. . That is, the first azimuth angle direction θa and the second azimuth angle direction θd are orthogonal to each other. As a result, a second alignment film (inorganic alignment film) subjected to the substantially vertical alignment process in the second azimuth angle direction θd is formed in the peripheral region E2 of the counter substrate 20. Then, the process proceeds to step S6.

  In the first alignment film formation step of step S6, as in the element substrate 10, as shown in FIG. 7, a substantially vertical alignment process in the first azimuth angle direction θa is performed on the display region E1 of the counter substrate 20. Specifically, silicon oxide is obliquely evaporated from the first azimuth angle direction θa to the display region E1 in a state where the peripheral region E2 of the counter substrate 20 is shielded by, for example, a mask. More specifically, when the substantially vertical alignment processing surface of the counter substrate 20 is turned down, oblique deposition is performed from a 45 ° direction from the lower left to the upper right in the drawing. As a result, a first alignment film (inorganic alignment film), that is, an alignment film 24 (see FIG. 3A) that has been subjected to a substantially vertical alignment process in the first azimuth angle direction θa is formed in the display region E1 of the counter substrate 20. Is done. Then, the process proceeds to step S7.

  In the liquid crystal injection / sealing process in step S7, the sealing material 40 is placed at a predetermined position using, for example, a printing method or a discharging method on either the element substrate 10 or the counter substrate 20 that has been subjected to the substantially vertical alignment process. Deploy. The element substrate 10 and the counter substrate 20 are arranged to face each other at a predetermined interval, and the sealing material 40 is cured. Then, liquid crystal having negative dielectric anisotropy is injected into the gap between the element substrate 10 and the counter substrate 20. Examples of the liquid crystal injection method include a vacuum injection method in which the gap between the element substrate 10 and the counter substrate 20 is decompressed and liquid crystal is injected into the gap from an injection port provided in the sealing material 40. The injection port provided in the sealing material 40 is sealed with, for example, an ultraviolet curable adhesive after the liquid crystal is injected. The liquid crystal injection / sealing method is not limited to this, and the sealing material 40 is arranged in a frame shape, and this is used as a bank, and the liquid crystal is dropped under reduced pressure on the inner side surrounded by the sealing material 40. A so-called ODF (One Drop Fill) method in which the substrate 10 and the counter substrate 20 are bonded together may be used.

According to the liquid crystal device 100 and the manufacturing method thereof according to the above embodiment, the following effects are obtained.
(1) The first alignment film subjected to the substantially vertical alignment process of the display area E1 provided with the plurality of pixels P1 is formed by obliquely depositing silicon oxide so that the azimuth angle θa with respect to the Y direction is 45 °. It is formed. On the other hand, the second alignment film that has been subjected to the substantially vertical alignment process in the peripheral region E2 in which the plurality of dummy pixels P2 are provided has a second azimuth angle direction θd that is orthogonal to the first azimuth angle direction θa. Similarly, it is formed by obliquely depositing silicon oxide. Accordingly, the ionic impurities in the liquid crystal move along the first azimuth angle direction θa and are transported toward the corners of the first azimuth angle direction θa of the display region E1, but the first azimuth angle in the peripheral region E2 It moves in the second azimuth angle direction θd that intersects the direction θa. Therefore, uneven distribution of ionic impurities at the corners in the first azimuth angle direction θa of the display region E1 is suppressed, and display unevenness due to the uneven distribution of ionic impurities is reduced.

  (2) In addition, the first azimuth angle direction θa in the substantially vertical alignment process with respect to the transmission axis or absorption axis of the polarizing elements 41 and 42 is set to 45 °, and the first azimuth angle direction θa and the second azimuth direction are set. Since the angular direction θd is orthogonal, there is no difference in optical characteristics between the display area E1 and the peripheral area E2. That is, even if the first azimuth direction θa in the display area E1 is different from the second azimuth direction θd in the peripheral area E2, light leakage does not occur from the peripheral area E2.

  (3) The first alignment film forming step of forming the first alignment film in which the display area E1 is subjected to the substantially vertical alignment process in the first azimuth angle direction θa is substantially perpendicular to the peripheral area E2 in the second azimuth angle direction θd. This is performed after the second alignment film forming step of forming the second alignment film subjected to the alignment treatment. Therefore, since the influence of the substantially vertical alignment treatment in the second azimuth angle direction θd does not affect the substantially vertical alignment treatment in the first azimuth angle direction θa in the display region E1, a stable alignment state of the liquid crystal molecules LC in the display region E1. Is obtained.

<Electronic equipment>
Next, the electronic apparatus of this embodiment will be described with reference to FIG. FIG. 8 is a schematic diagram illustrating a configuration of a projection display device as an electronic apparatus.

  As shown in FIG. 8, a projection display apparatus 1000 as an electronic apparatus according to this embodiment includes a polarized illumination apparatus 1100 arranged along the system optical axis L, and two dichroic mirrors 1104 and 1105 as light separation elements. Three reflection mirrors 1106, 1107, 1108, five relay lenses 1201, 1202, 1203, 1204, 1205, three transmissive liquid crystal light valves 1210, 1220, 1230 as light modulation means, and a light combining element As a cross dichroic prism 1206 and a projection lens 1207.

  The polarized light illumination device 1100 is generally configured by a lamp unit 1101 as a light source composed of a white light source such as an ultra-high pressure mercury lamp or a halogen lamp, an integrator lens 1102, and a polarization conversion element 1103.

  The dichroic mirror 1104 reflects red light (R) and transmits green light (G) and blue light (B) among the polarized light beams emitted from the polarization illumination device 1100. Another dichroic mirror 1105 reflects the green light (G) transmitted through the dichroic mirror 1104 and transmits the blue light (B).

The red light (R) reflected by the dichroic mirror 1104 is reflected by the reflection mirror 1106 and then enters the liquid crystal light valve 1210 via the relay lens 1205.
Green light (G) reflected by the dichroic mirror 1105 enters the liquid crystal light valve 1220 via the relay lens 1204.
The blue light (B) transmitted through the dichroic mirror 1105 enters the liquid crystal light valve 1230 via a light guide system including three relay lenses 1201, 1202, 1203 and two reflection mirrors 1107, 1108.

  The liquid crystal light valves 1210, 1220, and 1230 are disposed to face the incident surfaces of the cross dichroic prism 1206 for each color light. The color light incident on the liquid crystal light valves 1210, 1220, and 1230 is modulated based on video information (video signal) and emitted toward the cross dichroic prism 1206. In this prism, four right-angle prisms are bonded together, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface thereof. The three color lights are synthesized by these dielectric multilayer films, and the light representing the color image is synthesized. The synthesized light is projected on the screen 1300 by the projection lens 1207 which is a projection optical system, and the image is enlarged and displayed.

  The liquid crystal light valve 1210 is the one to which the liquid crystal device 100 described above is applied. The liquid crystal device 100 is arranged with a gap between a pair of polarizing elements arranged in crossed Nicols on the incident side and the emission side of colored light. The same applies to the other liquid crystal light valves 1220 and 1230.

  According to such a projection display device 1000, the liquid crystal device 100 in which uneven distribution of ionic impurities in the liquid crystal is suppressed is provided, and high display quality is realized.

  Various modifications other than the above embodiment are conceivable. Hereinafter, a modification will be described.

  (Modification 1) The method of the substantially vertical alignment treatment of the peripheral region E2 in the liquid crystal device 100 is not limited to this. FIG. 9 is a schematic plan view showing a method of a substantially vertical alignment process according to a modification. For example, as shown in FIG. 9, in the peripheral regions E3 and E4 along the corners in the first azimuth angle direction θa, a substantially vertical alignment process in the second azimuth angle direction θd orthogonal to the first azimuth angle direction θa is performed. A second alignment film is provided. In the peripheral regions E5 and E6 along the other corners, a first alignment film subjected to a substantially vertical alignment process in the first azimuth angle direction θa is provided. According to this, even if the ionic impurities have moved to all corners of the display area E1, the ionicity is prevented from being unevenly distributed at the corners in the peripheral areas E3, E4, E5, E6 corresponding to the respective corners. Impurities can be moved. That is, the substantially vertical alignment process in the peripheral region E2 may not be performed in a uniform azimuth direction, and ionic impurities are less likely to be unevenly distributed in view of the azimuth direction of the uniaxial substantially vertical alignment process in the display region E1. It should be set as follows.

  (Modification 2) Although the light shielding film 21 of the counter substrate 20 in the liquid crystal device 100 is disposed so as to surround the pixel region E including the display region E1 and the peripheral region E2, it is not limited to this. For example, the display area E1 may be provided so as to overlap the peripheral area E2 in plan view. Then, since the peripheral area E2 is shielded from light, there is no problem even if light leakage occurs in the peripheral area E2. That is, the second azimuth angle direction θd of the substantially vertical alignment process in the peripheral region E2 does not need to be orthogonal to the first azimuth angle direction θa. Therefore, the second azimuth angle direction θd does not need to have an intersecting angle of 45 ° with respect to the Y direction. From the viewpoint of suppressing the uneven distribution of ionic impurities at the corners, the second azimuth angle direction θd is parallel to the sides of the display region E1. What is necessary is just to set so that it may cross | intersect 1st azimuth angle direction (theta) a at the angle which does not become. In other words, the degree of freedom in setting the second azimuth angle direction θd is improved. Thereby, for example, in an oblique vapor deposition apparatus, the degree of freedom in design such as the arrangement of a substrate on which a substantially vertical alignment process is performed is improved, and a more compact vapor deposition apparatus design is possible.

  (Modification 3) The display area E1 in the liquid crystal device 100 is not limited to a quadrangle. For example, the present invention can be applied to a polygon such as a triangle having a corner and a pentagon.

  (Modification 4) The alignment films 18 and 24 in the liquid crystal device 100 are not limited to inorganic alignment films. For example, the present invention can also be applied to an organic alignment film in which a light-reactive organic film is irradiated with light such as ultraviolet rays based on the alignment direction and subjected to a substantially vertical alignment process.

  (Modification 5) The liquid crystal device 100 is not limited to the transmission type. The present invention can be applied even if the pixel electrode 15 is a reflective liquid crystal device 100 having light reflectivity.

  (Modification 6) The electronic apparatus to which the liquid crystal device 100 is applied is not limited to the projection display device 1000. For example, a projection-type HUD (head-up display), a direct-view HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, an LCD TV, a viewfinder-type or monitor-direct-view video recorder, car navigation It can be suitably used as a display unit of an information terminal device such as a system, electronic notebook, or POS.

  DESCRIPTION OF SYMBOLS 10 ... Element substrate, 18, 24 ... Alignment film | membrane, 20 ... Opposite substrate, 50 ... Liquid crystal layer, 100 ... Liquid crystal device, 1000 ... Projection type display apparatus as an electronic device, E1 ... Display area | region, E2 ... Peripheral area | region, P, P1... Pixel, P2... Dummy pixel.

Claims (10)

A liquid crystal device having a liquid crystal layer having negative dielectric anisotropy sandwiched between a pair of substrates and a display region including a plurality of pixels,
A first alignment film provided on each of the pair of substrates facing the liquid crystal layer in the display region, and subjected to a substantially vertical alignment process in a first azimuth angle direction;
A substantially vertical alignment process is performed in a second azimuth angle direction that is provided on each of the pair of substrates facing the liquid crystal layer in at least a part of a peripheral area surrounding the display area and intersects the first azimuth angle direction. A second alignment film formed;
A liquid crystal device comprising: The first alignment film is an inorganic alignment film in which a column is inclined in the first azimuth angle direction,
The liquid crystal device according to claim 1, wherein the second alignment film is an inorganic alignment film in which a column is inclined in the second azimuth angle direction. The display area is square in plan view,
3. The liquid crystal device according to claim 1, wherein the first azimuth angle direction is a direction that obliquely intersects a side portion of the display region. The first azimuth angle direction intersects the side of the display area at an angle of approximately 45 degrees,
The liquid crystal device according to claim 3, wherein the second azimuth angle direction intersects the first azimuth angle direction at an angle that is not parallel to a side portion of the display region. The second alignment film is provided in a portion of the peripheral region along a corner of the display region in the first azimuth direction,
5. The liquid crystal device according to claim 3, wherein the first alignment film is provided in a portion of the peripheral region along another corner of the display region.   The liquid crystal device according to claim 1, wherein a drivable dummy pixel is provided in the peripheral region. A method of manufacturing a liquid crystal device having a liquid crystal layer having negative dielectric anisotropy sandwiched between a pair of substrates and a display region including a plurality of pixels,
In each of the pair of substrates,
A first alignment film forming step of forming a first alignment film in which a substantially vertical alignment process is performed on the display region in a first azimuth angle direction;
A second alignment film forming step of forming a second alignment film in which at least a part of a peripheral region surrounding the display region is subjected to the substantially vertical alignment process in a second azimuth angle direction intersecting the first azimuth angle direction; A method of manufacturing a liquid crystal device, comprising: In the first alignment film forming step, the inorganic first alignment film having a column inclined in the first azimuth angle direction is formed;
8. The method of manufacturing a liquid crystal device according to claim 7, wherein in the second alignment film forming step, the inorganic second alignment film having a column inclined in the second azimuth angle direction is formed.   The method of manufacturing a liquid crystal device according to claim 7, wherein the first alignment film forming step is performed after the second alignment film forming step.   An electronic apparatus comprising the liquid crystal device according to claim 1.

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