JP4095256B2 - Liquid crystal device and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal device excellent in the display quality which can suppress display failure and disclination. SOLUTION: In the liquid crystal device, an inorganic alignment film 36 consisting of at least one kind of columnar structural material arranged as tilted in a specified direction is formed by an oblique vapor deposition method on the outermost surface in the liquid crystal layer 50 side of an active matrix substrate 10. An organic alignment film 42 consisting of aligning polymers and having the surface subjected to rubbing treatment is formed on the outermost surface of the counter substrate 20. The inorganic alignment film 36 and the organic alignment film 42 are preferably subjected to the aligning treatment to produce the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side larger than the pretilt angle of the liquid crystal molecules on the counter substrate 20.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal device and an electronic apparatus, and more particularly to an active matrix liquid crystal device that can suppress display defects and disclination and has excellent display quality.
[0002]
[Prior art]
An active matrix type liquid crystal device using a TFT (Thin-Film Transistor) element as a switching element has an active matrix substrate (element substrate) on which scanning lines, data lines, pixel electrodes, TFT elements, etc. are formed, and a common electrode. The counter substrate is arranged so as to be opposed to the counter substrate with a certain gap through a sealing material, and a liquid crystal layer is sandwiched between the gaps.
[0003]
More specifically, on the surface of the active matrix substrate on the liquid crystal layer side, a large number of data lines and a large number of scanning lines are provided in a grid pattern so as to intersect each other. Elements are formed, and pixel electrodes are connected through the respective TFT elements. Each pixel electrode and a region where a data line, a scanning line, a TFT element and the like arranged so as to surround each pixel electrode are pixels, and display is performed for each pixel arranged in a matrix. It is a possible structure.
[0004]
In addition, alignment films for bringing liquid crystal molecules in the liquid crystal layer into a predetermined alignment state when no voltage is applied are formed on the outermost surfaces of the active matrix substrate and the counter substrate on the liquid crystal layer side. Conventionally, as the alignment film, an organic alignment film made of an alignment polymer such as polyimide and whose surface is rubbed (rubbed in a certain direction using a cloth or the like) has been widely used.
[0005]
[Problems to be solved by the invention]
However, in an active matrix substrate, in general, in a region where a data line, a scanning line, a TFT element, etc. are formed, there are many layers formed as compared with a region where a pixel electrode is formed. The pixel periphery where lines, TFT elements, etc. are formed is higher than the pixel center where the pixel electrode is formed, and a step is easily formed between the pixel periphery and the pixel center on the active matrix substrate surface. .
[0006]
In particular, in recent years, since the size of each pixel is reduced in a liquid crystal device to achieve high definition, when the alignment film is rubbed, the rubbing cloth or the like does not contact the vicinity of the step, and the alignment film It is difficult to perform rubbing over the entire surface.
[0007]
If the rubbing treatment of the alignment film is insufficient at the boundary between the pixel peripheral edge and the pixel center, which is the vicinity of the step, that portion becomes an alignment film defect. It is not sufficiently regulated by the alignment film, resulting in an alignment failure state that takes an unstable alignment depending on various factors. As a result, when a voltage is applied, a reverse tilt domain (a region in which the rising direction of liquid crystal molecules is different) or the like occurs at the boundary between the pixel peripheral portion and the pixel central portion, and display defects such as light leakage may occur. .
[0008]
By the way, as one of the driving methods of the active matrix liquid crystal device, so-called frame inversion driving is known in which an image signal applied to the liquid crystal is inverted in every frame. Adopting frame inversion driving has the advantage of extending the life of the liquid crystal material, but flickering (image flickering) may occur due to crosstalk between adjacent pixels, which may degrade display quality. . In order to prevent flicker, line inversion driving for inverting the polarity of an image signal for each adjacent scanning line and column inversion driving for inverting for each adjacent data line are widely used.
[0009]
However, when line inversion driving or column inversion driving is employed, image signals having different polarities are supplied to adjacent pixels, so that the pixel electrode on the active matrix substrate and the common electrode on the counter substrate are not connected. In addition to the vertical electric field that directly contributes to driving the liquid crystal, a horizontal electric field is generated between adjacent pixel electrodes on the active matrix substrate. Disturbed, disclination occurs, and display defects such as light leakage may occur.
[0010]
The above problem is not limited to a liquid crystal device using a TFT element, and any active matrix liquid crystal device such as a liquid crystal device using a TFD (Thin-Film Diode) element may be used in a liquid crystal device having any structure. It is a problem that also occurs.
[0011]
Therefore, the present invention has been made in view of the above circumstances, and the adjacent first electrode group at the time of voltage application when a display defect due to an alignment film defect or line inversion driving or column inversion driving is adopted. An object of the present invention is to provide a liquid crystal device that can suppress disclination caused by a lateral electric field generated between the first electrode group and the second electrode group, and has excellent display quality, and an electronic device including the liquid crystal device. And
[0012]
[Means for Solving the Problems]
As a result of studies to solve the above problems, the present inventors have invented the following liquid crystal device of the present invention.
The liquid crystal device of the present invention is a liquid crystal device comprising an active matrix substrate and a counter substrate which are arranged to face each other with a liquid crystal layer interposed therebetween, and the liquid crystal layer side surface of the active matrix substrate is inclined in a specific direction. An inorganic alignment film made of at least one columnar structure arranged in an array is formed, and an organic alignment film made of an alignment polymer is formed on the liquid crystal layer side surface of the counter substrate. To do.
[0013]
In addition, the inorganic alignment film which consists of at least 1 type of columnar structure arranged in inclination in the specific direction can be formed using an oblique vapor deposition method. Here, the oblique vapor deposition method means that the deposition target substrate is fixed and the inorganic material is deposited from the direction inclined with respect to the deposition target substrate surface, thereby being arranged on the deposition target substrate surface with an inclination in the deposition direction. This is a method capable of forming a large number of columnar structures. In addition, in an inorganic alignment film, a desired alignment film (desired alignment direction or pretilt angle) can be obtained by controlling the tilt direction and tilt angle of the columnar structure, thereby adjusting the alignment of liquid crystal molecules. Can be regulated.
[0014]
In this way, unlike the organic alignment film, the inorganic alignment film does not require a rubbing process when forming the alignment film, so the organic alignment film is formed even if there are many steps on the base for forming the alignment film. An alignment film with fewer defects can be formed compared to the case. Therefore, by adopting a configuration in which the inorganic alignment film is formed on the active matrix substrate side where a step is likely to be formed on the surface, display defects caused by alignment film defects can be suppressed.
[0015]
However, when an inorganic alignment film is formed by one-step oblique vapor deposition, there are places where the inorganic material cannot be sufficiently deposited due to the shadow of the step due to the height of the step formed on the base, the deposition direction, etc. This may cause alignment film defects.
Therefore, it is preferable to form the inorganic alignment film by performing oblique vapor deposition from a plurality of directions when the active matrix substrate is viewed in plan. That is, it is preferable that the inorganic alignment film is composed of a plurality of types of columnar structures having different inclination directions when the active matrix substrate is viewed in plan. By adopting such a configuration, it is possible to form a defect-free inorganic alignment film regardless of the height of the step formed on the base, the vapor deposition direction, etc., suppressing display defects due to alignment film defects, A liquid crystal device with excellent display quality can be provided.
[0016]
In addition, the inorganic alignment film formed by using the oblique deposition method is inferior in terms of production cost and production efficiency as compared with the organic alignment film. Has the same structure as the conventional organic alignment film, so that the production cost can be reduced and the decrease in production efficiency can be suppressed as compared with the case where the inorganic alignment film is formed on both substrates. .
[0017]
In the liquid crystal device of the present invention described above, the active matrix substrate is adjacent to the first electrode group including a first electrode group including a plurality of electrodes arranged in one direction to which image signals having the same polarity are supplied. And a second electrode group composed of a plurality of electrodes arranged in one direction to which an image signal having a polarity different from that of the first electrode group is supplied, and the liquid crystal layer has a positive dielectric anisotropy. When applied to a liquid crystal device characterized by comprising liquid crystal, that is, a liquid crystal device adopting line inversion driving or column inversion driving as a driving method, further effects can be obtained.
[0018]
That is, when the liquid crystal device of the present invention is applied to a liquid crystal device employing line inversion driving or column inversion driving, line inversion driving or column inversion driving is adopted in addition to display defects due to alignment film defects. When voltage is applied, disclination caused by a lateral electric field generated between the adjacent first electrode group and the second electrode group can also be suppressed.
[0019]
More specifically, when forming an inorganic alignment film on the active matrix substrate side by oblique vapor deposition, an alignment film having a large pretilt angle can be stably formed, and the active matrix substrate side when no voltage is applied The pretilt angle of the liquid crystal molecules can be increased.
As a result, the pretilt angle of the liquid crystal molecules on the active matrix substrate side when no voltage is applied can be increased. As a result, the longitudinal direction of the liquid crystal molecules when no voltage is applied is represented by a vertical electric field (on the active matrix substrate) Generated between the pixel electrode and the common electrode on the counter substrate, and can be brought closer to the direction of the electric field directly contributing to the driving of the liquid crystal. Therefore, even when a horizontal electric field is generated between the adjacent first electrode group and the second electrode group during voltage application, the orientation conversion of the liquid crystal molecules that change the alignment along the vertical electric field proceeds more smoothly. Can be made.
[0020]
Thus, according to the present invention, by configuring the alignment film on the active matrix substrate side with the inorganic alignment film, the pretilt angle of the liquid crystal molecules on the active matrix substrate side when no voltage is applied can be increased. It is possible to provide a liquid crystal device with excellent display quality by suppressing disclination caused by a lateral electric field when a voltage is applied.
[0021]
When attention is paid only to the problem of disclination caused by a lateral electric field at the time of voltage application when line inversion driving or column inversion driving is adopted as a driving method, an image is displayed on the first electrode group and the second electrode group. A liquid crystal device in which a pretilt angle of liquid crystal molecules on the active matrix substrate side is larger than a pretilt angle of liquid crystal molecules on the counter substrate side among liquid crystal molecules constituting the liquid crystal layer in a state where no signal is supplied It can be said that it can be solved by.
[0022]
Here, the pretilt angle of the liquid crystal molecules on the active matrix substrate side in a state where no image signal is supplied to the first electrode group and the second electrode group is preferably 3 to 30 °. If the pretilt angle of the liquid crystal molecules on the active matrix substrate side exceeds 30 °, the light transmittance during white display decreases and the display becomes dark, which is not preferable.
[0023]
Further, when line inversion driving or column inversion driving is adopted, the liquid crystal molecules constituting the liquid crystal layer in the state in which no image signal is supplied to the first electrode group and the second electrode group, The liquid crystal molecules on the active matrix substrate side are preferably arranged so that the major axis direction thereof is substantially parallel to the arrangement direction of the plurality of electrodes in each of the first electrode group and the second electrode group.
[0024]
The present inventor has found that by adopting the above configuration, the influence of the lateral electric field at the time of voltage application when line inversion driving or column inversion driving is adopted can be further suppressed. Hereinafter, the reason will be briefly described with reference to FIG. FIG. 13A is a diagram schematically showing an enlarged surface of the active matrix substrate on the liquid crystal layer side. In FIG. 13A, each electrode of the first electrode group is denoted by reference numeral 100a, each electrode of the second electrode group is denoted by reference numeral 100b, each electrode 100a of the first electrode group, and each electrode of the second electrode group. A case where positive (+) and negative (-) potentials are applied to 100b is illustrated.
[0025]
As shown in FIG. 13A, when line inversion driving or column inversion driving is employed, each electrode 100a of the first electrode group and the second electrode group adjacent to the first electrode group when voltage is applied. The transverse electric field E between each electrode 100b _L Occurs. That is, the lateral electric field E is substantially perpendicular to the arrangement direction X (left-right direction in the drawing) of the electrodes 100a and 100b of the first electrode group and the second electrode group. _L Occurs.
[0026]
The alignment direction of the liquid crystal molecules on the active matrix substrate side when no voltage is applied is the lateral electric field E generated when the voltage is applied. _L When the voltage is applied, the horizontal electric field E is higher than the vertical electric field generated between the active matrix substrate and the counter substrate in the direction perpendicular to the paper surface. _L There is a possibility that the orientation change of the liquid crystal molecules that change the alignment along the vertical electric field may be hindered.
[0027]
On the other hand, in the case of the above configuration, that is, the liquid crystal molecules on the active matrix substrate side when no voltage is applied, the major axis direction and the arrangement direction X of the electrodes of the first electrode group and the second electrode group are approximately. When arranged in parallel, as shown in FIG. 13A, the alignment direction Ra of the liquid crystal molecules on the active matrix substrate side when no voltage is applied, and the lateral electric field E generated when the voltage is applied. _L Is shifted by approximately 90 ° from the direction of the horizontal electric field E. _L The lateral electric field E can be suppressed. _L Disclination caused by the can be suppressed.
[0028]
In FIG. 13A, the alignment direction of the liquid crystal molecules on the counter substrate side when no voltage is applied is indicated by Rb. FIG. 13A shows a case where a TN (Twisted Nematic) mode is adopted as the display mode, that is, a case where the twist angle of the liquid crystal is 90 °. However, the present invention is not limited to any display mode. It can also be applied to a liquid crystal device.
[0029]
Further, when line inversion driving or column inversion driving is adopted, the liquid crystal molecules constituting the liquid crystal layer in the state in which no image signal is supplied to the first electrode group and the second electrode group, The liquid crystal molecules on the active matrix substrate side are arranged so that the major axis direction thereof intersects the arrangement direction of the plurality of electrodes of each of the first electrode group and the second electrode group, and constitutes the liquid crystal layer The one end side in the major axis direction of the liquid crystal molecules to be extended straddles the formation region of the first electrode group and the formation region of the second electrode group in a plan view from the active matrix substrate side to the counter substrate side. The influence of the transverse electric field can be further suppressed by adopting a configuration in which the wires are twisted and arranged.
[0030]
The reason for this will be briefly described with reference to FIG. 13 (b) similar to FIG. 13 (a). In addition, the same referential mark is attached | subjected to the same component as Fig.13 (a), and description is abbreviate | omitted. In FIG. 13B, the case where the TN mode is adopted as the display mode will be described as an example. However, the present invention can be applied to any display mode liquid crystal device.
When the above configuration is adopted, as shown in FIG. 13B, the alignment direction Ra of the liquid crystal molecules on the active matrix substrate side when no voltage is applied is the electrodes 100a and 100b of the first electrode group and the second electrode group. Is set in a direction crossing the array direction X. In the TN mode, the alignment direction Rb of the liquid crystal molecules on the counter substrate side when no voltage is applied is set to a direction shifted by 90 ° from the alignment direction Ra.
[0031]
Further, when no voltage is applied, the liquid crystal molecules constituting the liquid crystal layer are arranged such that one end side in the major axis direction is viewed from the active matrix substrate side toward the counter substrate side in plan view and the first electrode group forming region and the second electrode They are twisted and arranged so as to straddle the formation region of the group. Specifically, for example, as shown in FIG. 13B, when no voltage is applied, the tip side (tip side of the arrow) of the alignment direction Ra of the liquid crystal molecules on the active matrix substrate side is the first electrode group side. If present, the liquid crystal molecules in the liquid crystal layer are twisted and arranged so that the front end side (the front end side of the arrow) of the alignment direction Rb of the liquid crystal molecules on the counter substrate side is the first electrode group side.
[0032]
When such a configuration is adopted, the alignment direction Ra of the liquid crystal molecules on the active matrix substrate side when no voltage is applied is set to a horizontal electric field E generated when the voltage is applied. _L Compared to the configuration shown in FIG. 13A in which the direction is substantially perpendicular to the direction of the horizontal direction E, the orientation direction Ra is a lateral electric field E generated when voltage is applied. _L If only the liquid crystal molecules on the active matrix substrate side are seen, the lateral electric field E _L The effect of is relatively large. However, in the case of the configuration shown in FIG. 13B, in the middle of the thickness direction of the liquid crystal layer, the orientation direction of the liquid crystal molecules when no voltage is applied, as in the configuration shown in FIG. Lateral electric field E generated when voltage is applied _L There is always a region where the direction of is substantially vertical. Therefore, for the liquid crystal molecules in this region, the transverse electric field E _L The horizontal electric field E _L It is possible to suppress the occurrence of disclination due to the above.
[0033]
However, the transverse electric field E _L Is strongly generated on the active matrix substrate side, the configuration shown in FIG. 13B has the orientation direction of the liquid crystal molecules when no voltage is applied and the transverse electric field E generated when the voltage is applied. _L The region in which the direction of is substantially vertical is the transverse electric field E _L This is particularly effective in the case where there is a strong occurrence of.
[0034]
As described above, according to the present invention, any one of a display defect due to an alignment film defect and a disclination due to a horizontal electric field at the time of voltage application when line inversion driving or column inversion driving is adopted. Alternatively, both can be suppressed, and a liquid crystal device with excellent display quality can be provided. In this specification, “when no voltage is applied” and “when voltage is applied” are respectively “when the applied voltage to the liquid crystal layer is lower than the threshold voltage of the liquid crystal” and “applied voltage to the liquid crystal layer”. Means that “is greater than or equal to the threshold voltage of the liquid crystal”.
In addition, by providing the above-described liquid crystal device of the present invention, an electronic apparatus having excellent display quality can be provided.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the structure of the liquid crystal device according to the embodiment of the present invention will be described in detail.
The liquid crystal device of this embodiment is an active matrix type liquid crystal device using a TFT element as a switching element, and particularly has a characteristic alignment film structure to be described later. In this embodiment, a case where the TN mode is adopted as the display mode will be described as an example.
[0036]
Hereinafter, the structure of the liquid crystal device of the present embodiment will be described with reference to FIGS. FIG. 1 is an equivalent circuit diagram of switching elements, signal lines and the like in a plurality of pixels arranged in a matrix constituting a display area of a liquid crystal device, and FIG. 2 is a TFT array in which data lines, scanning lines, pixel electrodes and the like are formed. 3 is a plan view of a plurality of adjacent pixel groups of the substrate (active matrix substrate), FIG. 3 is a cross-sectional view taken along line AA ′ in FIG. 2, and FIG. 4 is a cross-sectional view taken along line BB ′ in FIG. In addition, in each figure, in order to make each layer and each member the size which can be recognized on drawing, the scale is varied for every layer and each member.
[0037]
In the liquid crystal device of the present embodiment, as shown in FIG. 1, a plurality of pixels arranged in a matrix that constitutes an image display region are pixel electrodes 9 and switching elements for controlling the pixel electrodes 9. Each TFT element 30 is formed, and a data line 6 a to which an image signal is supplied is electrically connected to the source of the TFT element 30. The image signals S1, S2,..., Sn to be written to the data lines 6a are supplied line-sequentially in this order, or are supplied for each group to a plurality of adjacent data lines 6a. In addition, the scanning line 3a is electrically connected to the gate of the TFT element 30, and scanning signals G1, G2,..., Gm are applied to the plurality of scanning lines 3a in a pulse-sequential manner at predetermined timing. The The pixel electrode 9 is electrically connected to the drain of the TFT element 30, and the image signal S1, S2,..., Sn supplied from the data line 6a is turned on by turning on the TFT element 30 as a switching element for a certain period. Is written at a predetermined timing.
[0038]
A predetermined level of image signals S1, S2,..., Sn written to the liquid crystal via the pixel electrode 9 is held for a certain period with the common electrode described later. The liquid crystal modulates light by changing the orientation and order of the molecular assembly according to the applied voltage level, thereby enabling gradation display. Here, in order to prevent the held image signal from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9 and the common electrode.
[0039]
In the case of the liquid crystal device according to the present embodiment, as shown in FIG. 2, a plurality of transparent pixel electrodes 9 (outlined by dotted line portions 9A) are provided in a matrix on a TFT array substrate (active matrix substrate). A data line 6a, a scanning line 3a, and a capacitor line 3b are provided along the vertical and horizontal boundaries of the pixel electrode 9, respectively. In the present embodiment, each pixel electrode 9 and the area where the data line 6a, the scanning line 3a, the capacitor line 3b, etc. are arranged so as to surround each pixel electrode 9 are pixels, and are arranged in a matrix. The display can be displayed for each pixel.
[0040]
The data line 6a is electrically connected to a source region, which will be described later, of the semiconductor layer 1a made of, for example, a polysilicon film via a contact hole 5, and the pixel electrode 9 is a drain, which will be described later, of the semiconductor layer 1a. The region is electrically connected through a contact hole 8. In addition, the scanning line 3a is disposed so as to face a channel region (a region with a diagonal line rising to the left in the figure), which will be described later, of the semiconductor layer 1a. The scanning line 3a serves as a gate electrode at a portion facing the channel region. Function. The semiconductor layer 1a is not limited to polysilicon, and may be formed by bonding single crystal silicon, for example.
[0041]
The capacitance line 3b is formed from a main line portion (that is, a first region formed along the scanning line 3a in plan view) extending substantially linearly along the scanning line 3a and a location intersecting the data line 6a. And a protruding portion (that is, a second region extending along the data line 6 a when viewed in a plan view) protruding toward the previous stage (upward in the drawing) along the data line 6 a. In FIG. 2, a plurality of first light shielding films 11 a are provided in a region indicated by a diagonal line rising to the right.
[0042]
More specifically, the first light-shielding film 11a is provided at a position covering the TFT element 30 including the channel region of the semiconductor layer 1a in the pixel portion when viewed from the TFT array substrate side. The main line portion that extends in a straight line along the scanning line 3a opposite to the main line portion 3b, and protrudes from the position intersecting the data line 6a to the succeeding stage side (that is, downward in the figure) along the data line 6a. And a protrusion. The tip of the downward protruding portion in each stage (pixel row) of the first light shielding film 11a overlaps the tip of the upward protruding portion of the capacitor line 3b in the next stage under the data line 6a. A contact hole 13 for electrically connecting the first light-shielding film 11a and the capacitor line 3b to each other is provided at the overlapping portion. In other words, in the present embodiment, the first light shielding film 11a is electrically connected to the upstream or downstream capacitor line 3b through the contact hole 13.
[0043]
Next, looking at the cross-sectional structure, as shown in FIG. 3, the liquid crystal device of the present embodiment has a pair of transparent substrates, a TFT array substrate 10 forming one of the substrates, and an opposing arrangement thereto. And the counter substrate 20 forming the other substrate. Here, the TFT array substrate 10 is made of, for example, a quartz substrate or hard glass, and the counter substrate 20 is made of, for example, a glass substrate or quartz substrate. The TFT array substrate 10 is provided with pixel electrodes 9 made of a transparent conductive film such as indium tin oxide (hereinafter abbreviated as ITO), and adjacent to each pixel electrode 9 on the TFT array substrate 10. A pixel switching TFT element 30 for switching control of each pixel electrode 9 is provided at a position where the pixel electrode 9 is to be operated.
[0044]
The pixel switching TFT element 30 has an LDD (Lightly Doped Drain) structure, and includes a scanning line 3a, a channel region 1a ′ of the semiconductor layer 1a in which a channel is formed by an electric field from the scanning line 3a, and the scanning line 3a. Insulating thin film 2 that insulates semiconductor layer 1a, data line 6a, low concentration source region 1b and low concentration drain region 1c of semiconductor layer 1a, high concentration source region 1d and high concentration drain region 1e of semiconductor layer 1a Yes.
[0045]
Further, on the TFT array substrate 10 including the scanning line 3a and the insulating thin film 2, a contact hole 5 leading to the high concentration source region 1d and a contact hole 8 leading to the high concentration drain region 1e are respectively formed. A two-layer insulating film 4 is formed. That is, the data line 6 a is electrically connected to the high concentration source region 1 d through the contact hole 5 that penetrates the second interlayer insulating film 4. Further, on the data line 6a and the second interlayer insulating film 4, a third interlayer insulating film 7 in which a contact hole 8 leading to the high concentration drain region 1e is formed is formed. That is, the high concentration drain region 1 e is electrically connected to the pixel electrode 9 through the contact hole 8 that penetrates the second interlayer insulating film 4 and the third interlayer insulating film 7.
[0046]
In the present embodiment, as shown in FIGS. 3 and 4, the insulating thin film 2 serving as a gate insulating film is extended from a position facing the gate electrode formed as a part of the scanning line 3a and used as a dielectric film. The storage capacitor 70 is configured by extending the semiconductor layer 1a to form the first storage capacitor electrode 1f and further forming a part of the capacitor line 3b opposite to the second storage capacitor electrode.
[0047]
As shown in FIG. 3, at least the channel region 1a ′ of the semiconductor layer 1a and the low concentration source / drain region (LDD region) 1b, at positions corresponding to the pixel switching TFT elements 30 on the surface of the TFT array substrate 10, A first light-shielding film 11a is provided to prevent the return light from entering 1c. A first interlayer insulating film 12 is provided between the first light shielding film 11 a and the plurality of pixel switching TFT elements 30. The first interlayer insulating film 12 is provided to electrically insulate the semiconductor layer 1a constituting the pixel switching TFT element 30 from the first light shielding film 11a.
[0048]
As shown in FIGS. 2 and 3, in addition to providing the first light shielding film 11a on the TFT array substrate 10, the first light shielding film 11a is connected to the capacitor line 3b at the preceding stage or the subsequent stage through the contact hole 13. It is comprised so that it may electrically connect to. Further, in the first light shielding film 11a, the contact hole 13 is opened at the protruding portion protruding from the main line portion extending linearly as described above.
[0049]
On the other hand, the opposing substrate 20 has a second light-shielding region in the region opposite to the formation region of the data line 6a, the scanning line 3a, and the pixel switching TFT element 30 on the TFT array substrate 10, that is, in the region other than the opening region of each pixel portion. A film 23 is provided. Further, the common electrode 21 is provided over the entire surface of the counter substrate 20 including the second light shielding film 23. Similar to the pixel electrode 9 of the TFT array substrate 10, the common electrode 21 is also formed of a transparent conductive film such as ITO. Due to the presence of the second light-shielding film 23, incident light from the counter substrate 20 side enters the channel region 1a ′, the low-concentration source region 1b, and the low-concentration drain region 1c of the semiconductor layer 1a of the pixel switching TFT element 30. It has a structure that prevents intrusion.
[0050]
In this embodiment, an oblique deposition method is used for the outermost surface of the TFT array substrate 10 (on the pixel electrode 9 and on the third interlayer insulating film 7 in the region where the pixel electrode 9 is not formed). An inorganic alignment film 36 is formed which is formed by vapor-depositing an inorganic material and is made of at least one columnar structure arranged in a specific direction with an inclination. On the other hand, the outermost surface (on the common electrode 21) of the counter substrate 20 is made of an alignment polymer such as polyimide, and the surface is subjected to rubbing treatment (treatment using a cloth or the like for rubbing in a certain direction). A film 42 is formed. A liquid crystal layer 50 made of a liquid crystal having positive dielectric anisotropy is sandwiched between the TFT array substrate 10 and the counter substrate 20 (between the alignment films 36 and 42).
[0051]
As shown in FIG. 3, a number of layers are formed on the active matrix substrate 10, and the inorganic alignment film 36 is formed on the pixel electrode 9 and the third interlayer insulating film 7 having a number of steps on the surface. . In particular, on the surface of the base (the pixel electrode 9 and the third interlayer insulating film 7) on which the inorganic alignment film 36 is formed, the data line 6a, the scanning line 3a, the capacitor line 3b, the pixel switching TFT element 30, the first light shielding film 11a, etc. The pixel peripheral portion 81, which is a region where is formed, is from the pixel central portion 82 where these are not formed (the region where the pixel electrode 9 is formed, excluding the region where the capacitor line 3b and the like are formed). There are also many layers formed, and a large step 80 is formed between the pixel peripheral portion 81 and the pixel central portion 82.
[0052]
The height of the step 80 is, for example, about 200 to 1000 nm, and cannot be ignored with respect to the thickness of the inorganic alignment film 36 (for example, 5 to 50 nm). In recent years, with the increase in the definition of liquid crystal devices, it has been required to reduce the pixel pitch and increase the number of pixels, and the ratio of the step 80 formed on the active matrix substrate 10 to the pixel portion is as follows. It tends to increase.
[0053]
When an organic alignment film is formed on the active matrix substrate 10 side having many steps as described above, when rubbing the alignment film, the rubbing cloth or the like does not come into contact with the vicinity of the step 80, and the alignment film It is difficult to perform the rubbing process over the entire surface. As a result, an alignment film defect may occur, which may cause a display defect.
[0054]
However, in this embodiment, since there is no need for rubbing treatment on the active matrix substrate 10 side with many steps, an inorganic alignment that can be formed without being affected by the step 80 compared to the organic alignment film. Since the structure for forming the film 36 is employed, the alignment film 36 with few defects can be formed, and display defects due to the alignment film defects can be suppressed.
[0055]
However, in the case where the inorganic alignment film 36 is formed by one-step oblique vapor deposition, there is a portion where the inorganic material cannot be sufficiently deposited due to the shadow of the step due to the height of the step formed on the base or the deposition direction. This may cause alignment film defects.
Therefore, it is preferable to perform oblique vapor deposition from a plurality of directions to form the inorganic alignment film 36 in a plan view of the active matrix substrate 20, and to form the inorganic alignment film 36 on the base by forming the inorganic alignment film 36 in this way. Regardless of the height of the step, the deposition direction, and the like, the alignment film 36 having no defect can be formed, and disclination when no voltage is applied due to the alignment film defect can be suppressed.
[0056]
Here, a method for forming the inorganic alignment film 36 by a plurality of stages of oblique vapor deposition will be specifically described by taking as an example the case of forming the inorganic alignment film 36 by two stages of oblique vapor deposition. For example, as shown in FIG. 7, the first oblique deposition is performed in a deposition direction S with a deposition angle (angle formed with the surface of the TFT array substrate 10) θ1. _A The second oblique deposition is performed in the first deposition direction S when the active matrix substrate 10 is viewed in plan view. _A Deposition direction S with an angle φ apart from the deposition angle θ2. _B By performing from the above, it becomes a shadow of a step in the first oblique vapor deposition, and the inorganic material can be sufficiently vapor deposited by the second oblique vapor deposition on the portion where the inorganic material is not sufficiently vapor deposited. Here, it is preferable to set the second deposition angle θ2 larger than the first deposition angle θ1.
[0057]
In the second oblique deposition, the deposition is performed on a region near a step that is not sufficiently deposited by the first oblique deposition or a region that is sufficiently deposited by the first oblique deposition. Depending on the second deposition direction, a part that becomes a shadow of a step may be newly generated. Therefore, the inorganic alignment film 36 formed by the two-stage oblique deposition is a portion where only the columnar structure generated by the first oblique deposition exists, and the columnar structure generated by the second oblique deposition. In which the two types of columnar structures produced by the first oblique deposition and the second oblique deposition are mixed, and the direction of the inclination is viewed in plan view of the active matrix substrate 10. A plurality of types of columnar structures with different values are mixed.
[0058]
In contrast, the counter substrate 20 has fewer layers formed than the active matrix substrate 10, and the second light shielding film 23 and the common electrode 21 are disposed between the counter substrate 20 and the organic alignment film 42. Is only formed. Therefore, the organic alignment film 42 is formed on the base (common electrode 21) with few steps on the surface. Thus, since there are few steps on the counter substrate 20 side, even if an organic alignment film is formed, it can be satisfactorily rubbed over the entire surface, and the alignment film 42 without defects can be formed. it can. In addition, since organic alignment films have lower production costs and superior production efficiency compared to inorganic alignment films, production costs can be kept lower than when inorganic alignment films are formed on both substrates. A decrease in efficiency can be suppressed, which is preferable.
[0059]
Next, an alignment process for the inorganic alignment film 36 and the organic alignment film 42 will be described.
In the case of the liquid crystal device of the present embodiment, in order to realize the TN mode display mode, the alignment process is performed so that the alignment directions of the inorganic alignment film 36 and the organic alignment film 42 on each substrate are twisted by 90 °. Is given. That is, as shown in FIG. 2, the inorganic alignment film 36 on the TFT element array substrate 10 has a direction from the left to the right in the drawing along the extending direction of the scanning line 3a (the direction indicated by the solid arrow Ra). The alignment direction is such that the organic alignment film 42 on the counter substrate 20 has a direction from the bottom to the top in the figure along the extending direction of the data line 6a (the direction indicated by the broken arrow Rb). Each of the orientation treatments is performed.
[0060]
Further, in this embodiment, when no voltage is applied, the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side is larger than the pretilt angle of the liquid crystal molecules on the counter substrate 20 side, that is, the inorganic alignment film 36 The alignment treatment is performed so that the pretilt angle is larger than the pretilt angle of the organic alignment film 42. Specifically, when no voltage is applied, the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side is preferably 3 to 30 °, and the pretilt angle of the liquid crystal molecules on the counter substrate 20 side is smaller than this, for example, It is preferable to set it as 1-3 degree. Note that it is not preferable that the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side when no voltage is applied exceeds 30 °, because the light transmittance during white display decreases and the display becomes dark.
[0061]
In this specification, when the inorganic alignment film 36 has a plurality of alignment directions and pretilt angles, the “alignment direction” and “pretilt angle” of the inorganic alignment film 36 are “average alignment direction”, It means “average pretilt angle”.
[0062]
In the organic alignment film 42, the alignment direction and the pretilt angle can be controlled by controlling the rubbing direction and the like when forming the organic alignment film 42.
On the other hand, in the inorganic alignment film 36, the surface shape can be controlled by controlling the vapor deposition direction of the inorganic material when forming the inorganic alignment film 36, and the desired alignment direction and pretilt angle can be set. Obtainable. When the inorganic alignment film is formed by the oblique deposition method, an alignment film having a high pretilt angle can be stably obtained as compared with the case of forming the organic alignment film made of the alignment polymer.
[0063]
In the case where the inorganic alignment film 36 is formed by one-step oblique deposition, the alignment direction and the pretilt angle of the inorganic alignment film 36 depend on the size and pitch of the columnar structure to be generated. This corresponds to the inclination direction and the inclination angle of the generated columnar structure.
On the other hand, when the inorganic alignment film 36 is formed by oblique deposition in a plurality of stages, the obtained inorganic alignment film 36 is in a state where a plurality of types of columnar structures are mixed, so that the alignment of the inorganic alignment film 36 is performed. Although the direction and the pretilt angle have a distribution, in general, the columnar structures formed by the second and subsequent oblique depositions are formed so as to fill the gaps between the columnar structures formed by the first oblique deposition. The overall average orientation direction and pretilt angle are substantially defined by the surface shape of the columnar structure formed by the first oblique deposition.
[0064]
Thus, in this embodiment, the inorganic alignment film 36, the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side is larger than the pretilt angle of the liquid crystal molecules on the counter substrate 20 side when no voltage is applied. Since the organic alignment film 42 is subjected to an alignment process, when line inversion driving or column inversion driving is employed as a driving method, in addition to the vertical electric field that directly contributes to driving of the liquid crystal when voltage is applied. This has the effect of suppressing disclination caused by a lateral electric field generated on the active matrix substrate 10 side.
[0065]
The line inversion driving is a driving method in which the polarity of the image signal is inverted for each adjacent scanning line 3a, while the column inversion driving inverts the polarity of the image signal for each adjacent data line 6a. In the following, an example in which line inversion driving is employed will be described.
[0066]
As described above, line inversion driving is a system in which the polarity of an image signal is inverted for each adjacent scanning line 3a. Hereinafter, a plurality of pixel electrodes 9 adjacent in a direction along one scanning line 3a (lateral direction in FIG. 2) are defined as a first electrode group, and each of the plurality of pixel electrodes 9 and a direction along the data line 6a ( A plurality of pixel electrodes 9 that are adjacent to each other in the vertical direction in FIG. 2 and adjacent to the direction along one scanning line 3a (lateral direction in FIG. 2) will be described as a second electrode group.
[0067]
When line inversion driving is employed, when an image signal having a positive polarity (+) is supplied to the first electrode group in an arbitrary frame, an image signal having a negative polarity (−) is supplied to the second electrode group. Then, the polarity is inverted in the next frame, and when a negative (−) image signal is supplied to the first electrode group, a positive (+) image signal is supplied to the second electrode group. In addition, when viewed from the individual pixel electrodes 9 in the first electrode group and the second electrode group, image signals having different polarities are supplied to the two pixel electrodes 9 arranged in the vertical direction in FIG. .
[0068]
Based on FIG. 8, an electric field generated in the liquid crystal layer 50 when a voltage is applied when line inversion driving is employed will be described. FIG. 8 is a schematic cross-sectional view of the liquid crystal device of the present embodiment, and schematically shows the state of an electric field generated when a voltage is applied to each pixel electrode 9 and common electrode 21. In FIG. 8, it is assumed that the left pixel electrode 9 and the right pixel electrode 9 belong to the first electrode group and the second electrode group, respectively, and are denoted by reference numerals 9a and 9b, respectively. In the following description, it is assumed that a positive potential is applied to the pixel electrode 9a of the first electrode group, a negative potential is applied to the pixel electrode 9b of the second electrode group, and a ground potential is applied to the common electrode 21.
[0069]
As shown in FIG. 8, when a potential is applied to each electrode, a vertical electric field E directed from the pixel electrode 9a to the common electrode 21 at the center of the pixel electrode 9a of the first electrode group. _V Occurs in the central portion of the pixel electrode 9b of the second electrode group, and the vertical electric field E from the common electrode 21 toward the pixel electrode 9b. _V Occurs. These vertical electric fields E _V Is an electric field that directly contributes to driving of the liquid crystal.
[0070]
On the other hand, on the active matrix substrate 10, since different potentials are applied to the pixel electrode 9a of the first electrode group and the pixel electrode 9b of the second electrode group adjacent thereto, A lateral electric field E from the pixel electrode 9a toward the pixel electrode 9b of the second electrode group _L Occurs. This transverse electric field E _L Is not generated to drive the liquid crystal, but naturally occurs.
[0071]
In the present embodiment, when the voltage is not applied, the pretilt angle of the liquid crystal molecules on the active matrix substrate 10 side is configured to be larger than the pretilt angle of the liquid crystal molecules on the counter substrate 20 side. Longitudinal direction of liquid crystal molecules on the active matrix substrate 10 side is defined as a vertical electric field E generated when voltage is applied. _V It is possible to approach the direction of (electric field that directly contributes to driving of the liquid crystal). Accordingly, when a voltage is applied, a lateral electric field E is generated between the pixel electrode 9a of the adjacent first electrode group and the pixel electrode 9b of the second electrode group. _L Even when the vertical electric field E _V The orientation change of the liquid crystal molecules that change the alignment along the horizontal direction can proceed more smoothly, and the lateral electric field E during voltage application can be increased. _L Disclination caused by the can be suppressed.
[0072]
Furthermore, in this embodiment, when no voltage is applied, the liquid crystal molecules on the active matrix substrate 10 side are substantially parallel to the major axis direction and the arrangement direction of the pixel electrodes 9a and 9b of the first electrode group and the second electrode group. It is preferable that they are arranged so that
That is, the relationship between the alignment direction Ra of the liquid crystal molecules on the active matrix substrate 10 side when no voltage is applied and the arrangement direction of the pixel electrodes 9a and 9b of the first electrode group and the second electrode group is shown in FIG. It is preferable that the relationship shown in FIG. With this relationship, as described in the section “Means for Solving the Problems”, the alignment direction Ra of the liquid crystal molecules on the active matrix substrate 10 side when no voltage is applied and the horizontal direction generated when the voltage is applied. Electric field E _L Is shifted by approximately 90 ° from the direction of the horizontal electric field E. _L The lateral electric field E can be suppressed. _L The disclination caused by this can be further suppressed.
[0073]
Further, in the present embodiment, when no voltage is applied, the liquid crystal molecules on the active matrix substrate 10 side are such that the major axis direction and the arrangement direction of the pixel electrodes 9a and 9b of the first electrode group and the second electrode group intersect. The liquid crystal molecules constituting the liquid crystal layer 50 are arranged such that one end side in the major axis direction is planarly viewed from the active matrix substrate 10 side to the counter substrate 20 side and the first electrode group forming region and the first It is good also as a structure arrange | positioned twisting so that the formation area of 2 electrode groups may be straddled.
[0074]
That is, the relationship between the alignment direction Ra of the liquid crystal molecules on the active matrix substrate 10 side when no voltage is applied and the arrangement direction of the electrodes 9a and 9b of the first electrode group and the second electrode group is shown in FIG. The relationship shown may be used. Even in such a relationship, as described in the section “Means for Solving the Problems”, in the middle of the thickness direction of the liquid crystal layer 50, the alignment direction of the liquid crystal molecules and the voltage when no voltage is applied. Lateral electric field E generated during application _L Since there is always a region in which the direction of is substantially vertical, the liquid crystal molecules in this region are _L The horizontal electric field E _L It is possible to suppress the occurrence of disclination due to the above.
[0075]
In the present embodiment, the case where the TN mode is adopted as the display mode has been described as an example. However, the present invention is not limited to the TN mode in which the twist angle of the liquid crystal is 90 °. Is also applicable.
Accordingly, the alignment direction Ra of the liquid crystal molecules on the active matrix substrate 10 side when no voltage is applied, the alignment direction Rb of the liquid crystal molecules on the counter substrate 20 side, and the pixel electrodes 9a and 9b of the first electrode group and the second electrode group. It goes without saying that various patterns other than the relationships shown in FIGS. 13A and 13B can be considered as the relationship with the arrangement direction.
[0076]
In this embodiment, an example in which line inversion driving is adopted as the driving method has been described. However, the present invention can also be applied to the case in which column inversion driving is adopted. Also in this case, if the direction of the horizontal electric field, the orientation direction, etc. in the description of the case of line inversion driving are considered to be rotated by 90 °, the same operation can be obtained, and the same effect can be obtained.
[0077]
In the present embodiment, only the case where many steps are formed on the base surface of the inorganic alignment film 36 of the active matrix substrate 10 has been described. However, the present invention is not limited to this, and the inorganic alignment film A configuration may be employed in which the underlying surface of 36 is flattened and the inorganic alignment film 36 is formed thereon. In this case, when the inorganic alignment film 36 is formed, the inorganic alignment film 36 having no defect can be formed by one-step oblique deposition, which is preferable.
[0078]
Hereinafter, the means for flattening the base of the inorganic alignment film 36 will be described with an example.
For example, as shown in FIG. 5, the surface of the active matrix substrate 10 is etched, and a groove 10a having a predetermined depth is dug in advance in the pixel peripheral portion 81 for forming the data line 6a, the capacitor line 3b, and the like. If the data line 6a, the capacitor line 3b and the like are formed so as to be embedded, the surface of the base (the pixel electrode 9 and the third interlayer insulating film 7) of the inorganic alignment film 36 can be substantially flattened.
[0079]
Alternatively, as shown in FIG. 6, a third interlayer insulating film 7 covering the data line 6a, the capacitor line 3b, etc. is once formed thick, and then the surface of the third interlayer insulating film 7 is formed using a CMP (Chemical Mechanical Polishing) method. By forming the pixel electrode 9 after polishing and flattening, the surface of the base (the pixel electrode 9 and the third interlayer insulating film 7) of the inorganic alignment film 36 can be substantially flattened.
[0080]
As another method for finally forming a structure similar to that shown in FIG. 6, the third interlayer insulating film 7 is formed of BPSG (Boron Phosphorus Silicate Glass), and then the BPSG film is reflowed by heat treatment. The surface of the three interlayer insulating film 7 may be planarized. Or if the 3rd interlayer insulation film 7 is originally formed with films | membranes, such as SOG (Spin On Glass) with high fluidity, the surface with high flatness will be obtained. Note that the planarization process using the interlayer insulating film is not limited to the third interlayer insulating film 7, and the planarization may be performed using the second interlayer insulating film 4 or a plurality of interlayer insulating films. Needless to say.
[0081]
In this embodiment, only the liquid crystal device using the TFT element has been described, but the present invention can be applied to an active matrix liquid crystal device having any structure such as a liquid crystal device using a TFD element.
[0082]
As described above, according to the liquid crystal device of the present embodiment, the display defect due to the alignment film defect and the adjacent first electrode group at the time of voltage application when line inversion driving or column inversion driving is adopted. Both the disclination caused by the transverse electric field generated between the second electrode group can be suppressed, and an active matrix liquid crystal device with excellent display quality can be provided.
[0083]
[Electronics]
Hereinafter, a projection display device will be described as an example of an electronic apparatus using the liquid crystal device.
FIG. 9 is a schematic configuration diagram showing an example of a so-called three-plate type projection liquid crystal display device using three liquid crystal light valves. Here, the liquid crystal device of the above embodiment is used as a liquid crystal light valve. In the figure, reference numeral 510 is a light source, 513 and 514 are dichroic mirrors, 515, 516 and 517 are reflection mirrors, 518, 519 and 520 are relay lenses, 522, 523 and 524 are liquid crystal light valves, 525 is a cross dichroic prism, and 526 Indicates a projection lens system.
[0084]
The light source 510 includes a lamp 511 such as a metal halide and a reflector 512 that reflects light from the lamp 511. The blue light / green light reflecting dichroic mirror 513 transmits red light of white light from the light source 510 and reflects blue light and green light. The transmitted red light is reflected by the reflection mirror 517 and is incident on the red light liquid crystal light valve 522.
[0085]
On the other hand, among the color lights reflected by the dichroic mirror 513, green light is reflected by the dichroic mirror 514 that reflects green light and enters the green liquid crystal light valve 523. On the other hand, the blue light also passes through the second dichroic mirror 514. For blue light, in order to compensate for the difference in optical path length from green light and red light, a light guide means 521 comprising a relay lens system including an incident lens 518, a relay lens 519, and an exit lens 520 is provided. Through this, the blue light is incident on the liquid crystal light valve 524 for blue light.
[0086]
The three color lights modulated by the respective light valves enter the cross dichroic prism 525. 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. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected on the screen 527 by the projection lens system 526 which is a projection optical system, and the image is enlarged and displayed.
[0087]
According to this projection type liquid crystal display device, an image with high display quality can be obtained by providing the liquid crystal device of the above embodiment as a liquid crystal light valve.
[0088]
Hereinafter, other examples of the electronic device will be described.
FIG. 10 is a perspective view showing an example of a mobile phone. In FIG. 10, reference numeral 1000 denotes a mobile phone body, and reference numeral 1001 denotes a liquid crystal display unit using the liquid crystal display device.
FIG. 11 is a perspective view showing an example of a wristwatch type electronic apparatus. In FIG. 11, reference numeral 1100 denotes a watch body, and reference numeral 1101 denotes a liquid crystal display unit using the liquid crystal display device.
[0089]
FIG. 12 is a perspective view showing an example of a portable information processing apparatus such as a word processor or a personal computer. In FIG. 12, reference numeral 1200 denotes an information processing apparatus, reference numeral 1202 denotes an input unit such as a keyboard, reference numeral 1204 denotes an information processing apparatus body, and reference numeral 1206 denotes a liquid crystal display unit using the liquid crystal display device.
[0090]
Since the electronic apparatus shown in FIGS. 10 to 12 includes a liquid crystal display unit using the liquid crystal device of the above embodiment, an image with excellent display quality can be obtained.
The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the specific configuration of the liquid crystal device described with reference to FIGS. 2 and 3 is merely an example, and the present invention can be applied to other liquid crystal devices having various configurations.
[0091]
【The invention's effect】
As described above in detail, according to the present invention, by forming alignment films having different structures on the active matrix substrate side and the counter substrate side, display defects caused by alignment film defects, line inversion driving, and column Either or both of disclinations caused by a lateral electric field generated between the adjacent first electrode group and the second electrode group can be suppressed during voltage application when employing inversion driving. A liquid crystal device with excellent display quality and an electronic device including the same can be provided.
[Brief description of the drawings]
FIG. 1 is an equivalent circuit diagram of switching elements, signal lines and the like in a plurality of pixels arranged in a matrix constituting a display region of a liquid crystal device according to an embodiment of the present invention.
FIG. 2 is a plan view of a plurality of pixels.
FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG.
4 is a cross-sectional view taken along line BB ′ of FIG.
FIG. 5 is a cross-sectional view corresponding to FIG. 4 showing another example of the cross-sectional structure.
6 is a cross-sectional view corresponding to FIG. 4 showing still another example of the cross-sectional structure.
FIG. 7 is a view for explaining a vapor deposition direction when forming an inorganic alignment film by a plurality of stages of oblique vapor deposition.
FIG. 8 is a diagram schematically showing the state of an electric field generated when a voltage is applied when line inversion driving or column inversion driving is adopted as a driving method.
FIG. 9 is a diagram illustrating an example of a projection display device including the liquid crystal device.
FIG. 10 illustrates an example of an electronic device including the liquid crystal device.
FIG. 11 is a diagram showing another example of the electronic device.
FIG. 12 is a diagram showing still another example of the electronic device.
FIG. 13 is a diagram showing the relationship between the orientation direction of liquid crystal molecules when no voltage is applied and a lateral electric field generated when a voltage is applied when line inversion driving or column inversion driving is adopted as a driving method.
[Explanation of symbols]
3a Scan line
3b capacitance line
6a Data line
9 Pixel electrode
9a, 100a Pixel electrode of first electrode group
9b, 100b Pixel electrode of second electrode group
10 TFT array substrate (active matrix substrate)
20 Counter substrate
21 Common electrode
30 TFT element for pixel switching
36 Inorganic alignment film
42 Organic alignment film
50 Liquid crystal layer
70 storage capacity
80 steps
81 Pixel edge
82 pixel center
Ra Orientation direction on the active matrix substrate side
Rb Orientation direction on opposite substrate

Claims (5)

In a liquid crystal device comprising an active matrix substrate and a counter substrate that are arranged to face each other with a liquid crystal layer interposed therebetween,
The liquid crystal layer side surface of the active matrix substrate is formed with an inorganic alignment film made of at least one kind of columnar structure that is inclined in a specific direction, and the liquid crystal layer side surface of the counter substrate is formed. An organic alignment film made of an alignment polymer is formed,
The active matrix substrate includes a first electrode group composed of a plurality of electrodes arranged in one direction to which image signals of the same polarity are supplied, and a polarity different from that of the first electrode group adjacent to the first electrode group A second electrode group consisting of a plurality of electrodes arranged in one direction to which the image signal is supplied,
The liquid crystal layer is made of a liquid crystal having positive dielectric anisotropy,
In a state where no image signal is supplied to the first electrode group and the second electrode group,
Among the liquid crystal molecules constituting the liquid crystal layer, the pretilt angle of the liquid crystal molecules by the inorganic alignment film on the active matrix substrate side is larger than the pretilt angle of the liquid crystal molecules by the organic alignment film on the counter substrate side,
In a state where no image signal is supplied to the first electrode group and the second electrode group, among the liquid crystal molecules constituting the liquid crystal layer, the liquid crystal molecules on the active matrix substrate side are arranged in the major axis direction and the first direction. A liquid crystal device, characterized in that one electrode group and the second electrode group are arranged so that the arrangement directions of a plurality of electrodes are substantially parallel to each other. In a liquid crystal device comprising an active matrix substrate and a counter substrate that are arranged to face each other with a liquid crystal layer interposed therebetween,
The liquid crystal layer side surface of the active matrix substrate is formed with an inorganic alignment film made of at least one kind of columnar structure that is inclined in a specific direction, and the liquid crystal layer side surface of the counter substrate is formed. An organic alignment film made of an alignment polymer is formed,
The active matrix substrate includes a first electrode group composed of a plurality of electrodes arranged in one direction to which image signals of the same polarity are supplied, and a polarity different from that of the first electrode group adjacent to the first electrode group A second electrode group consisting of a plurality of electrodes arranged in one direction to which the image signal is supplied,
The liquid crystal layer is made of a liquid crystal having positive dielectric anisotropy,
In a state where no image signal is supplied to the first electrode group and the second electrode group,
Among the liquid crystal molecules constituting the liquid crystal layer, the pretilt angle of the liquid crystal molecules by the inorganic alignment film on the active matrix substrate side is larger than the pretilt angle of the liquid crystal molecules by the organic alignment film on the counter substrate side,
In a state where no image signal is supplied to the first electrode group and the second electrode group, among the liquid crystal molecules constituting the liquid crystal layer, the liquid crystal molecules on the active matrix substrate side are arranged in the major axis direction and the first direction. The liquid crystal molecules constituting the liquid crystal layer are arranged so that the arrangement direction of the plurality of electrodes of each of the one electrode group and the second electrode group intersects, and one end side in the major axis direction of the active matrix substrate A liquid crystal device, wherein the liquid crystal device is arranged to be twisted so as to straddle the formation region of the first electrode group and the formation region of the second electrode group in plan view from the side toward the counter substrate side.   3. The liquid crystal device according to claim 1, wherein the inorganic alignment film is composed of a plurality of types of columnar structures having different inclination directions when the active matrix substrate is viewed in plan. In a state where no image signal is supplied to the first electrode group and the second electrode group,
4. The liquid crystal device according to claim 1, wherein a pretilt angle of liquid crystal molecules on the active matrix substrate side is 3 to 30 degrees.   An electronic apparatus comprising the liquid crystal device according to any one of claims 1 to 4.

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