JP4101341B2 - Electro-optical device and projection device - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
  The present invention relates to a liquid crystal electro-optical device using a display body such as a liquid crystal, and more particularly to its configuration.
[0002]
[Prior art]
  A CRT is the most common display device. However, the CRT has a large volume, weight, and power consumption, and is not particularly suitable for a display device with a large area. Therefore, in recent years, attention has been paid to a liquid crystal electro-optical device (direct-view type or projection type) that can easily realize lighter weight, lower power consumption, and larger screen than CRT.
[0003]
  The liquid crystal electro-optical device utilizes the fact that the liquid crystal substance has different dielectric constants in the direction parallel to and perpendicular to the molecular axis, and controls on / off, that is, light and dark by controlling the polarization of light, the amount of transmitted light, and the amount of scattering. indicate. As the liquid crystal material, nematic liquid crystal, ferroelectric liquid crystal, and anti-ferroelectric liquid crystal are generally used.
[0004]
  In particular, among liquid crystal electro-optical devices, semiconductor devices having TFTs on an insulating substrate such as glass, for example, active matrix liquid crystal electro-optical devices using thin film transistors (TFTs) for driving pixels have been actively developed. .
[0005]
  Examples of the display method of the active matrix type liquid crystal electro-optical device include a transmission type, a reflection type, and a transflective type. Among these, the reflective liquid crystal electro-optical device has an advantage that the aperture ratio of the pixel can be made higher than that of the transmissive type, particularly for a small type having a size of 2.5 inches diagonal or less. Suitable for use with other projectors.
[0006]
  FIG. 16 shows a simplified diagram of a projection type projector using a reflective liquid crystal panel as an example of a conventional electro-optical device. For simplicity, FIG. 16 does not show an optical system (condensing lens, total reflection mirror, etc.), and only the light source 11, the liquid crystal panel 13, the PBS (polarization beam splitter) 12, and the screen 14 are clearly shown. A conventional configuration is shown below.
[0007]
  In FIG. 16, a light source 11 having a strong white light is used, and a metal halide lamp is mainly used.
[0008]
  The liquid crystal panel 13 is an active matrix reflective liquid crystal panel having a configuration in which signal lines and scanning lines are combined in a matrix on a glass substrate and TFTs are arranged in the vicinity of the intersections. In this configuration, the source electrode of the TFT is connected to the signal line, and the gate electrode is connected to the scanning line. The drain electrode is connected to a pixel reflection electrode arranged corresponding to the storage capacitor and the liquid crystal in the pixel region. The liquid crystal is driven while being sandwiched between the counter electrode and the pixel reflection electrode. This liquid crystal panel uses an ECB mode (electric field control type birefringence mode) utilizing the birefringence effect of liquid crystal. The counter electrode is formed on the counter substrate.
[0009]
  The PBS (polarized beam splitter) 12 is a polarizer having the functions of a polarizing plate and a beam splitter. The PBS has a cube shape in which the inclined surfaces of a pair of right-angle prisms are bonded together. The slope to be bonded is usually coated with a dielectric multilayer film.
[0010]
  Further, as shown in FIG. 18, the PBS 12 is branched into two linearly polarized light beams (P-polarized light and S-polarized light) whose polarization planes are orthogonal to each other on the bonding surface, and has a branch angle of exactly 90 °. Hold and exit from two adjacent outer surfaces of the cube. Of the two branched light beams, a light beam emitted from a direction of 0 ° with respect to the incident direction of the incident light beam is polarized light whose electric field vector is parallel to the incident surface defined by the dielectric multilayer coating layer. The light is emitted as a linearly polarized light having a plane (P-polarized light). On the other hand, a light beam emitted from a direction of 90 ° with respect to the incident direction of the incident light beam has a polarization plane (S-polarized light) whose electric field vector is perpendicular to the incident surface defined by the dielectric multilayer coating layer. It is emitted as a linearly polarized light.
[0011]
  In the case of normal projection, the screen 14 may have a white flat surface. However, in the case of rear projection (where the image can be observed from the screen surface opposite to the light source), a transmissive diffusion screen is used.
[0012]
  The display principle of the conventional projection apparatus (FIGS. 16 and 17) will be described below. FIGS. 16 and 17 are simplified diagrams, and an infrared ray or ultraviolet ray cut filter, a fly eye that performs uniforming optical processing, a monochromating optical system that divides into RGB, a polarizing plate, a mirror, and the like are not shown for simplification.
[0013]
  First, light composed of unpolarized light having a single wavelength is emitted from the light source 11, and the unpolarized or previously polarized light is applied to the outer surface of the PBS 12 (45 with respect to the dielectric multilayer coating layer on the bonding surface). Incident to °).
[0014]
  Next, the light beam incident on the outer surface of the PBS is branched with a branch angle of exactly 90 ° with respect to the incident surface, and the light beam having the P-polarized component and the light beam having the S-polarized component from the PBS. Is emitted.
[0015]
  Thereafter, only the S-polarized light beam emitted from the PBS enters the reflective liquid crystal panel 13. The light beam incident on the liquid crystal panel is optically modulated by the liquid crystal, reflected by the reflective electrode, and again incident on the PBS. At this time, the alignment processing direction or rubbing direction for aligning the liquid crystal has a direction of 45 ° with respect to the S-polarized light axis in order to make the best use of the birefringence effect.
[0016]
  The modulated light beam incident on the PBS 12 again is branched into the light beam having the P-polarized component and the light beam having the S-polarized component, and only the light beam having the P-polarized component of the light beam incident on the PBS is directed to the screen 14. And is adjusted by an optical system or a polarizing plate to form an image on the screen 14.
[0017]
[Problems to be solved by the invention]
  A scenario assuming a conventional reflective LCD panelMu19 to 22 show the results of the simulation (using the programs “3DBENCH” and “2DBENCH” in the software “LCD MASTER” of Shintech Co., Ltd.). ShiMuData, liquid crystal data (physical properties of liquid crystal materials: ordinary light refractive index, extraordinary light refractive index, pretilt angle, elastic constant, rotational viscosity coefficient, dielectric constant, etc.), polarizer angle, analyzer angle, etc. are input. As a model, two pixels (28 μm × 28 μm) arranged in parallel were driven by alternating current (applied voltage: ± 5 V).
[0018]
  Figure 6MuFixed conditions andMuThe parameters are shown. Based on FIG.MuIn FIG. 19, which is the result of the adjustment, two parallel pixels (vertical 30 μm × horizontal 60 μm: distance between pixel electrodes = 2 μm, pixel electrode size [vertical 28 μm × horizontal 28 μm]) are shown. Indicates the brightness of the reflected light. As shown in FIG. 19, the brightness of the reflected light, that is, the reflectance decreases as it approaches the end of the pixel electrode.
[0019]
  As described above, the conventional configuration has a problem in that the reflectance of the pixel electrode, that is, the brightness characteristic is deteriorated, as shown in FIG.
[0020]
  As shown in FIGS. 4 (1) to (3) and FIG. 5, with respect to an effective electric field (positive or negative) perpendicular to the paper surface applied to the pixel, an electric field is generated between adjacent pixels by line inversion driving. Since the domain of liquid crystal alignment, that is, disclination occurs in this portion, the brightness characteristic is deteriorated.
[0021]
  In addition, FIG.MuThe horizontal axis is the distance (horizontal width of the pixel), and the vertical axis is the brightness of the reflected light (that is, the reflectance) with respect to the brightness of the incident light of the liquid crystal panel. Figure 8MuFixed conditions andMuThe parameters are shown. The pixel electrodes 1 and 2 in FIG. 8 are the same as those shown in FIGS.2The pixel electrodes 1 and 2 in FIG. 20 shows a pretilt angle = 85 °, FIG. 21 shows a pretilt angle = 87 °, and FIG. 22 shows a pretilt angle = 89 °. As shown in FIGS. 20-22, the brightness | luminance of reflected light, ie, the brightness, is reducing as the pretilt angle becomes large.
[0022]
  As described above, in the conventional configuration, the brightness, that is, the brightness of the reflected light depends on the pretilt angle.
[0023]
  The present invention provides means for solving the above problems. More specifically, in particular, a means for obtaining bright display characteristics with good reflectivity (or transmittance) of a liquid crystal panel is disclosed, and an electro-optical device with reduced disclination using the means is disclosed. With the goal.
[0024]
[Means for Solving the Problems]
  The first configuration of the present invention disclosed in this specification is:
  A thin film transistor is connected to an intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column,
In the electro-optical device, the liquid crystal molecules are aligned in a direction parallel or substantially parallel to a direction in which the signal lines extend.
[0025]
  In the first configuration, the electro-optical device includes:GateIt is characterized by line inversion drive.
[0026]
  The second configuration of the present invention is as follows.
  A thin film transistor is connected to an intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column,
In the electro-optical device, the liquid crystal molecules are aligned in a direction parallel or substantially parallel to a direction in which the scanning lines extend.
[0027]
  In the second configuration, the electro-optical device includes:SourceIt is characterized by line inversion drive.
[0028]
  In the above structure, the major axis of the liquid crystal molecule is characterized by being perpendicular or substantially perpendicular to the substrate when no voltage is applied.
[0029]
  In the above configuration, the electro-optical device includes a reflective liquid crystal display element.
[0030]
  In the above-described configuration, the electro-optical device includes a transmissive liquid crystal display element.
[0031]
  The third configuration of the present invention is as follows.
  A first substrate having a pixel electrode connected to a thin film transistor connected to the intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column;
A second substrate disposed opposite the first substrate;
An electro-optical device including a liquid crystal display element including a liquid crystal layer made of a liquid crystal material disposed between a first substrate and a second substrate.
  The major axis component direction of the liquid crystal molecules without an electric field projected onto the first substrate is:
By using a method of driving the liquid crystal material by a line inversion method in which the voltage applied to the pixel electrode is inverted in polarity every certain period, it is parallel or substantially parallel to the direction of the lines of electric force generated between adjacent pixel electrodes. Is an electro-optical device.
[0032]
  The fourth configuration of the present invention is as follows.
  A first substrate having a pixel electrode connected to a thin film transistor connected to the intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column;
A second substrate disposed opposite the first substrate;
An electro-optical device including a liquid crystal display element including a liquid crystal layer made of a liquid crystal material disposed between a first substrate and a second substrate.
  The alignment processing direction of the liquid crystal layer is in a direction of electric lines of force generated between adjacent pixel electrodes by using a method of driving a liquid crystal material by a line inversion method in which the polarity of a voltage applied to the pixel electrode is inverted every certain period. The electro-optical device is parallel or substantially parallel.
[0033]
  The fifth configuration of the present invention is as follows.
  A thin film transistor is connected to an intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column, and a first electrode including a pixel electrode connected to the thin film transistor and an alignment film. A substrate of
A second substrate disposed opposite to the first substrate and provided with an alignment film;
An electro-optical device including a liquid crystal display element including a liquid crystal layer made of a liquid crystal material disposed between a first substrate and a second substrate.
  The rubbing direction applied to the alignment film of the first substrate is set between adjacent pixel electrodes by using a method of driving a liquid crystal material by a line inversion method in which a voltage applied to the pixel electrodes is inverted in polarity every predetermined period. An electro-optical device that is parallel or substantially parallel to a direction of a generated electric force line.
[0034]
  The sixth configuration of the present invention is as follows.
  A thin film transistor is connected to an intersection of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column, and a first electrode including a pixel electrode connected to the thin film transistor and an alignment film. A substrate of
A second substrate disposed opposite to the first substrate and provided with an alignment film;
An electro-optical device including a liquid crystal display element including a liquid crystal layer made of a liquid crystal material disposed between a first substrate and a second substrate.
  The rubbing direction applied to the alignment film of the second substrate is determined between the adjacent pixel electrodes by using a method of driving the liquid crystal material by a line inversion method in which the voltage applied to the pixel electrodes is inverted in polarity every certain period. An electro-optical device that is parallel or substantially parallel to a direction of a generated electric force line.
[0035]
  In any of the above configurations 3 to 6, the pixel electrode is formed of a reflective metal film or dielectric multilayer film, or a laminate thereof.
[0036]
  In the above structures 3 to 6, the liquid crystal display element is a transmissive type.
[0037]
  In the above configurations 3 to 6, the pixel electrode has a reflective liquid crystal display element, a light source, a polarizing beam splitter, a screen,
In an electro-optical device comprising: optical means for projecting light modulated by the liquid crystal display element onto the screen;
The absolute value of the angle formed by the side direction of the exit surface of the polarizing beam splitter that emits the light from the light source to the liquid crystal display element side and the direction in which the scanning line of the liquid crystal display element extends is 45 degrees or It is approximately 45 degrees.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
  The liquid crystal electro-optical device of the present invention is characterized by the relationship between the alignment processing direction or rubbing direction 110 of the liquid crystal panel 103 as shown in FIGS. 1 and 2 and the electric force line direction 111 generated by the alternating drive method.
[0039]
  First, the electric field line direction 111 in the horizontal direction generated by the AC drive method, which causes disclination, will be described below.
[0040]
  In general, in a liquid crystal display using TFT, in order to prevent deterioration of liquid crystal material, eliminate display unevenness, and maintain display quality, the voltage applied to each pixel is a voltage obtained by reversing the positive / negative for every frame or every fixed period. Is applied (alternating current).
[0041]
  When the cycle of reversing positive and negative (polarity reversal cycle) is long, it becomes a frequency range (about 30 Hz) that can be visually recognized by human eyes. Therefore, when the polarity of the video signal is positive and the polarity of the video signal is negative The slight difference from the display of was seen by the observer as flickering.
[0042]
  One of the conventional AC driving methods (source line inversion) in the conventional liquid crystal display panel display will be described below. Here, for simplification, a model screen (FIGS. 4 (3) (a) and 4 (3) (b)) of 4 rows × 5 columns of display pixels, which is a part of the display area of the liquid crystal panel, is used. Illustrated. 4 is a top view of a state diagram of electric lines of force generated between the two pixel electrodes 1 and 2 with respect to an effective electric field (positive or negative) perpendicular to the paper surface applied to the pixel electrodes 1 and 2. (1) and sectional view are shown in FIG. However, for the sake of convenience, FIG. 4 (1) shows only the electric lines of force generated between the pixel electrodes 1 and 2 generated in the horizontal direction, and FIG. 4 (2) shows that the vertically aligned liquid crystal molecules are applied to the application of an electric field. The phase diagram of the electric field lines immediately before the reaction is shown.
[0043]
  As an AC driving method for liquid crystal display panel display with reduced flickering, as shown in the display pattern diagrams in FIGS. 4 (3) (a) and 4 (3) (b), every time one adjacent signal line is written. In addition, an alternating method (source line inversion method) in which the polarity of a video signal is inverted and applied to a pixel has been proposed. In this method, a video signal having a polarity opposite to that of pixels adjacent in the horizontal (horizontal) direction is applied to each pixel. In the next screen (frame), a video signal having a polarity opposite to that of the previous screen (frame) is applied to each pixel. The alternating drive is performed by repeating this operation.
[0044]
  When AC driving by the above source line inversion method is performed, as shown in FIGS. 4C and 4C, a potential difference is generated between adjacent pixels, so that the direction of electric lines of force (electric field direction) is in the horizontal (horizontal) direction. 111 is formed.
[0045]
  Conventionally, the electric field in the horizontal (horizontal) direction is not taken into consideration, and in order to make the best use of the birefringence effect of the liquid crystal, as shown in FIGS. On the other hand, the rubbing direction 16 was set to an angle of 45 degrees or -45 degrees, and the rubbing process or the orientation process was performed.
[0046]
  As another inversion method, as shown in FIGS. 5A and 5B, an alternating method (gate line) in which the polarity of a video signal is inverted and applied to a pixel every time one adjacent scanning line is written. Inversion method) has been proposed. When AC driving is performed by the gate line inversion method, as shown in FIG. 5C, similarly, a potential difference is generated between adjacent pixels, so that the direction of electric force lines (electric field direction) in the vertical (vertical) direction is the same. It is formed. Conventionally, even when AC driving is performed by gate line inversion, the electric field in the vertical (vertical) direction is not taken into consideration, and the rubbing direction with respect to the S-polarized light axis is 45 degrees or − The angle was set to 45 degrees, and rubbing treatment or orientation treatment was performed.
[0047]
  The present inventors have disclination when the direction 111 of the electric lines of force generated by this AC drive system (source line inversion, gate line inversion) and the alignment processing direction of the liquid crystal or the rubbing direction 110 of the alignment film are parallel. It has been found that the display characteristics (transmittance, reflectance, brightness, etc.) of the liquid crystal panel are improved.
[0048]
  Therefore, as shown in FIG. 2 (1), the configuration of the present invention is a liquid crystal panel configuration in which the electric force line direction 111 and the alignment treatment direction or rubbing direction 110 coincide, that is, the alignment with respect to the electric force line direction 111. The liquid crystal panel configuration was such that the processing direction or rubbing direction 110 was parallel or substantially parallel. With such a configuration of the present invention, the major axis component direction of liquid crystal molecules projected on the substrate plane when no electric field is applied (when no voltage is applied) is the lines of electric force generated by the lateral electric field when line inversion driving is performed. Parallel to or substantially parallel to the direction 111. In addition, the major axis component direction of the liquid crystal molecules projected onto the substrate plane when no electric field is parallel or substantially parallel to the alignment treatment direction or the rubbing direction 110.
[0049]
  Here, if the liquid crystal panel has a liquid crystal panel structure with no rubbing scratches as a rubbing-less without rubbing treatment, better display can be obtained. However, in the case of rubbing-less, the major axis component direction of the liquid crystal molecules projected on the substrate plane when no electric field is applied is parallel or substantially parallel to the electric force line direction 111 by alignment treatment.
[0050]
  By using the configuration of the present invention, the fixing condition shown in FIG.Mu3DMuFIG. 7 shows the result of the calibration. In addition, the fixed condition shown in FIG.MuTwo-dimensionalMuThe results of the calibration are shown in FIGS. The horizontal axis is the distance (horizontal width of the pixel), and the vertical axis is the brightness of the reflected light (that is, the reflectance) with respect to the brightness of the incident light of the liquid crystal panel. From this result, it is shown that a good display with high reflectance can be obtained by the configuration of the present invention regardless of the liquid crystal material.
[0051]
  In addition, the configuration of the present invention corresponds to the configuration of the liquid crystal panel 103 (the configuration in which the alignment processing direction or the rubbing direction 110 is parallel or substantially parallel to the electric force line direction 111), and the arrangement of the PBS 102 and the light source 101. Was configured as shown in FIG. 1 and FIG. 2 (2). FIG. 2 (2) shows a case where the PBS is seen from the back surface of the liquid crystal panel when the screen side liquid crystal panel surface is the front surface.
[0052]
  In the present invention, the light source 101 and the PBS 102 are set so that the rubbing direction is at an angle of 45 degrees or −45 degrees with respect to the light axis direction of the S-polarized light in order to make maximum use of the birefringence effect of the liquid crystal as in the conventional case. The arrangement of was appropriately changed.
[0053]
  That is, in the configuration of the present invention, the angle formed by the side direction of the exit surface of the PBS 102 that emits light from the light source to the liquid crystal panel side and the row direction of the liquid crystal panel 102 (direction in which the scanning lines of the liquid crystal panel extend) is formed. Was 45 degrees or approximately 45 degrees. This angle may be within 43 to 47 degrees. In addition, the arrangement of the light source 101 was appropriately changed so that the light emitted from the light source was incident on the outer surface of PBS (45 ° with respect to the dielectric multilayer coating surface of the bonding surface). In addition, the phase plate may be used without changing the arrangement in this way.
[0054]
  In addition, the fixing conditions shown in FIG. 8 (however, because of the transmission type, the cell thickness was 4.8 μm),MuThe two-dimensional system assuming a transmission type liquid crystal panel using the configuration of the present invention with the adjustment parameter (pretilt angle = 85 degrees).MuFIG. 24 shows the result of the measurement. The horizontal axis is the distance (horizontal width of the pixel), and the vertical axis is the brightness of the transmitted light (that is, the transmittance) relative to the brightness of the incident light of the liquid crystal panel. This result (FIG. 24) shows that even when the structure of the present invention is applied to a transmissive liquid crystal panel, a good display with high transmittance is obtained regardless of the liquid crystal material.
[0055]
  In addition, the fixing conditions shown in FIG. 8 (however, because of the transmission type, the cell thickness was 4.8 μm),MuTwo-dimensional display assuming a conventional transmissive liquid crystal panel with a calibration parameter (pretilt angle = 85 degrees).MuFIG. 25 shows the result of the measurement. Similar to the results of the conventional reflection type liquid crystal panel (FIGS. 20 to 22), also in FIG. 25, the brightness of the transmitted light, that is, the transmittance, decreases as it approaches the end of the pixel.
[0056]
  In this specificationMuThe simulation result is a simplified model used to confirm the tendency of brightness (reflectance or transmittance), and actually differs from the display characteristic value determined by various factors.
[0057]
  Needless to say, the present invention can be applied to either a reflective LCD or a transmissive LCD as a method for improving the brightness of a liquid crystal panel.
[0058]
  Further, in the present invention, when no voltage is applied, the major axis of the liquid crystal molecules is perpendicular or substantially perpendicular to the substrate, that is, vertical alignment. Further, in this specification, as shown in FIG. 23, an angle formed by the major axis 2303 of the liquid crystal molecules when no voltage is applied to the substrate plane 2300 is a pretilt angle 2302. In addition, FIG. 23 shows the major axis component direction 2304 of the liquid crystal molecules when no electric field is projected onto the substrate plane. Here, 2301 is a liquid crystal molecule, and 2305 is a normal line of the substrate plane.
[0059]
  In this specification, the long side direction of the outer peripheral edge of the liquid crystal panel 103 in FIG. 1 is a row direction (horizontal direction), and the short side direction is a column direction (vertical direction). Specifically, the direction in which the scanning lines extend is the row direction, and the direction in which the signal lines extend is the column direction. That is, in the liquid crystal panel of the present invention, the alignment process direction or rubbing direction is the row direction in the case of source line inversion driving, and the alignment processing direction or rubbing direction is the column direction in the case of gate line inversion driving.
[0060]
【Example】
  Examples of the present invention will be described below, but the present invention is not limited to these examples.
  [Example 1]
  This example shows an outline of a manufacturing process of a liquid crystal panel. This embodiment will be described with reference to FIG.
[0061]
[Liquid crystal panel manufacturing process 1]
  FIG. 12 shows a manufacturing process of a typical top-gate thin film transistor using a crystalline silicon semiconductor (polysilicon).
[0062]
  First, a substrate 800 having high heat resistance (a quartz substrate in this embodiment) is prepared, and an insulating silicon film having a thickness of 300 nm is formed on the substrate as a base film (not shown). The insulating silicon film is any one of a silicon oxide film (SiOx), a silicon nitride film (SixNy), a silicon oxynitride film (SiOxNy), or a laminated film thereof.
[0063]
  Alternatively, a glass substrate (typically a material called crystallized glass, glass ceramics, or the like) can be used if the strain point is 750 ° C. or higher. In that case, it is effective to provide a base film by a low pressure thermal CVD method and surround the entire surface of the substrate with an insulating silicon film to suppress outflow of component substances from the glass substrate. Also, it is possible to cover the entire surface of the substrate with an amorphous silicon film and completely transform it into a thermal oxide film.
[0064]
  Then, an island-shaped semiconductor region (silicon island) made of a crystalline silicon film was formed by a known method. [FIG. 12A] The thickness of the crystalline silicon film 803 greatly affects the characteristics of the required semiconductor circuit, but may be 20 to 100 nm, preferably 15 to 45 nm. In this example, it was 45 nm. In this embodiment, it is preferable to use a crystalline silicon semiconductor (polysilicon) as the semiconductor material of the TFT of the driving portion. That is, it is preferable to use a silicon semiconductor having crystallinity, which has excellent physical properties such as conductivity and can be driven at high speed as compared with amorphous silicon, as a semiconductor material of the TFT of the driving portion. As silicon semiconductors having crystallinity, polycrystalline silicon, microcrystalline silicon, amorphous silicon containing crystal components, semi-amorphous silicon having an intermediate state between crystalline and amorphous are known. .
[0065]
  In this embodiment, the silicon film having crystallinity may be formed by using any known means. However, since it is desirable to suppress the shrinkage of the substrate as much as possible and minimize the displacement of the wiring pattern, the nickel film The technique described in Japanese Patent Laid-Open No. 8-78329, which can lower the crystallization temperature and shorten the annealing time by adding, for example, as a catalyst element.
[0066]
  In this example, after obtaining a silicon film having crystallinity by the technique described in the publication, gettering means using phosphorus [heat treatment at 500 to 700 ° C.] (Japanese Patent Application No. 9-65406) The catalyst elements used for crystallization are reduced. In addition, the catalytic element may be reduced by performing heat treatment (at 700 ° C. to 1000 ° C.) in an atmosphere containing a halogen element (Japanese Patent Application No. 8-301249).
[0067]
  Then, after forming a gate insulating layer by plasma CVD method or thermal CVD method, it is good also as a structure which performs a thermal oxidation process and obtains a silicon oxide film. Further, aluminum or a material containing aluminum as a main component (in this embodiment, an aluminum film containing 2 wt% scandium) was formed and patterned to form a gate electrode 801 and a wiring. The gate wiring may be silicon, a metal such as tungsten or titanium, or a silicide thereof. What kind of material is used for the gate electrode 801 may be determined depending on the required characteristics of the semiconductor circuit, the heat-resistant temperature of the substrate, and the like.
[0068]
  Next, a porous anodic oxide film and a non-porous anodic oxide film 809 are formed by the technique described in JP-A-7-135318. Then, using the anodic oxide film and the gate electrode 801 as a mask, the gate insulating layer is etched to form a gate insulating film 802. Thereafter, the porous anodic oxide film is removed. [FIG. 12 (B)]
[0069]
  After that, an N-type or P-type impurity is introduced into the silicon island by means of ion doping or the like in a self-aligned manner to form a channel formation region 810, a low concentration impurity region 811, and a source region 812 and a drain region 813. did. [FIG. 12 (C)]
[0070]
  Then, an interlayer insulating film 808 was deposited by a known means. Then, a contact hole was opened in this, and an aluminum alloy wiring was formed to obtain a source electrode 805 and a drain electrode 806. [FIG. 12D]
[0071]
  Further, a silicon nitride film or the like having a thickness of 10 to 50 nm is deposited thereon as a protective film (passivation film) by a plasma CVD method, and a contact hole that leads to the wiring of the output terminal is formed in the silicon nitride film. It is good also as a structure which forms. As the protective film, a silicon oxide film, an organic resin film, or a laminated film thereof may be used in addition to the silicon nitride film.
[0072]
  Thereafter, although not shown, the pixel electrode is formed by a sputtering method or the like using a material mainly composed of Al, Ti, or the like. In this embodiment, a reflective liquid crystal display device using Al as a pixel electrode is manufactured. However, a transmissive liquid crystal display device can also be manufactured using ITO as a pixel electrode.
[0073]
  In this way, a thin film transistor was formed on the substrate to produce a panel array substrate. This thin film transistor is mainly used as a driving circuit or a switching element of a pixel.
[0074]
  Next, an alignment film is formed on the panel array substrate and / or the counter substrate (the substrate on which the counter electrode is formed), and is heated and cured (baked). Next, a rubbing process is performed in which the substrate surface to which the alignment film is attached is rubbed in a certain direction with a buff cloth (fibers such as rayon and nylon) having a length of 2 to 3 mm to create fine grooves. In addition to rubbing treatment with a cloth or the like, the orientation treatment can be performed by an oblique vapor deposition method, a temperature gradient method, a photo-alignment method, or the like. A rubbing process is performed on either the panel array substrate or the counter substrate. In order to avoid damage to the TFT element and simplify the process, in this embodiment, only the counter substrate was rubbed.
[0075]
  In order to avoid damage to the TFT element and simplify the process, it is preferable to align the liquid crystal only by alignment treatment such as oblique vapor deposition, temperature gradient method, and photo-alignment method without performing the rubbing step. .
[0076]
  Further, when the rubbing process is performed on both the panel array substrate and the counter substrate, the rubbing is performed so as to be anti-parallel (anti-parallel) when bonded.
[0077]
  In this step, the rubbing direction was set to the same direction as the direction of electric lines of force (row direction) generated between adjacent pixels when AC driving was performed. That is, the rubbing direction and the direction of the electric lines of force generated between the pixels are matched, and the angle formed by the rubbing direction and the direction of the electric lines of force is approximately 0 °. By doing so, it is possible to prevent the brightness of the reflected light from being lowered and to keep the brightness of the reflected light constant regardless of the pretilt angle.
[0078]
  Thereafter, spherical spacers such as polymer, glass, and silica are dispersed on either the panel array substrate or the counter substrate.
[0079]
  Next, a resin serving as a sealing material provided on the outer frame of the substrate is applied to either the panel array substrate or the counter substrate.
[0080]
  After the sealing material is provided, the counter substrate and the panel array substrate are bonded together. In this way, the liquid crystal material is injected from the liquid crystal injection port of the panel formed by bonding the panel array substrate and the counter substrate, and then the liquid crystal injection port is sealed with an epoxy resin. A panel is produced as described above. At this time, the liquid crystal is vertically aligned. When rubbing is not performed (rubbing-less), the liquid crystal is vertically aligned according to the alignment processing direction.
[0081]
  In this embodiment, a top gate structure (typically a planar TFT) is manufactured as a driver circuit or a pixel switching element. However, a bottom gate TFT (typically an inverted stagger type) is used. TFT) may be used. Example 2 shows a manufacturing process of a typical bottom-type gate TFT.
[0082]
  [Example 2]
  This example shows an outline of a manufacturing process of a liquid crystal panel as in Example 1. This embodiment will be described with reference to FIG.
[0083]
[Liquid crystal panel manufacturing process 2]
  FIG. 13 shows a manufacturing process of a typical bottom-gate thin film transistor using a crystalline silicon semiconductor (polysilicon) used as a switching element used in a pixel matrix.
[0084]
  First, a base film made of an insulating film containing silicon as a main component is formed on a glass substrate 900 (or quartz or silicon substrate). A gate electrode 901 (first wiring) made of a conductive film is formed thereon. Here, the first patterning step (gate electrode formation) is performed.
[0085]
  The thickness of the gate electrode 901 is preferably 200 to 500 nm. In this embodiment, a Ta film having a thickness of 300 nm is used. As the gate electrode 901, a heat-resistant material (tantalum, tungsten, titanium, chromium, molybdenum, conductive silicon, or the like) that can withstand a temperature of at least about 600 ° C. can be used.
[0086]
  Next, a gate insulating layer 902 made of a silicon nitride film, a silicon oxynitride film represented by SiOxNy or a silicon oxide film (thickness is preferably 10 to 200 nm. In this embodiment, TEOS and oxygen which are organosilanes are used. And a silicon oxynitride film having a thickness of 125 nm is used by plasma CVD. (FIG. 13 (A))
[0087]
  Next, an amorphous silicon film was formed as an active layer on the surface of the gate insulating layer from which the carbon contaminants were removed by the above method. The amorphous silicon has a thickness of about 5 to 300 nm, and typically has a thickness of 40 to 100 nm. As a film forming method, a plasma CVD method, a low pressure thermal CVD method, a sputtering method or the like could be used. In this example, a 50 nm film was formed by plasma CVD.
[0088]
  Thereafter, amorphous silicon may be used as the active layer as it is, but it is desirable to use a silicon film having high field effect mobility (mobility) and crystallinity. Amorphous silicon may be crystallized by any known method (solid phase growth by heat treatment, etc.).To theIt was further crystallized to be polycrystallized (polysiliconized).
[0089]
  As a laser condition, a so-called excimer laser such as ArF, ArCl, KrF, KrCl, XeF, or XeCl is used as a laser source. As the irradiation energy, the exit energy from the laser body is 400 to 1000 mJ, the laser is processed by an optical system, and the surface of the substrate 301 is 150 to 500 mJ / cm.²Irradiate to the extent. The energy is the energy per one time of the laser. The substrate temperature is heated to room temperature to 300 ° C. The repetition frequency of irradiation is about 20 to 100 Hz, the moving speed of the laser on the substrate 301 is 1 to 5 mm / second, and the stage is moved by scanning the beam or placing the substrate 301 on the moving stage. .
[0090]
  In this example, a KrF excimer laser is used, and the main body outlet output is 550 to 650 mJ, and 180 to 230 mJ / cm on the substrate.²Then, the stage on which the substrate was placed was moved at a speed of 2.0 to 3.0 mm / sec at an irradiation repetition frequency of 35 to 45 Hz.
[0091]
  Further, if the hydrogen in the amorphous silicon is not removed to some extent before crystallization, there is a case where a hole is formed in a severe case because hydrogen suddenly goes out of the amorphous by heating. Therefore, it is effective to put a hydrogen desorption step in nitrogen at 400 to 500 ° C. for 0.5 to 5 hours before crystallization. Typically performed at 400 ° C. for 1-2 hours in nitrogen.
[0092]
  Then, using a known photolithography method, the resist is patterned to form a mask, and the polysilicon is CF_Four+ O₂Etching was performed using dry etching using, and then the resist was stripped using an alkaline stripping solution to form islands. Here, 903 is a polysilicon island (made of a crystalline silicon film).
[0093]
  Next, a silicon oxide film (preferably with a thickness of 100 to 300 nm, in this embodiment, with a thickness of 150 nm) is formed to cover the polysilicon island 903, and then patterned to protect the channel formation region. An etching stopper 909 was formed. (Fig. 13 (C))
[0094]
  After forming the etching stopper, Al, doped polysilicon, Cr, Ta, etc. are laminated as the first conductive film 907 to be the source / drain region, and the second electrode to become the drain electrode 905 and the source electrode 906 is formed thereon. As the conductive film 904, Al, Ti, Cr, Ta, etc. were continuously laminated. In this embodiment, doped polysilicon obtained by doping amorphous silicon is used as the first conductive film 907. This doping is performed by ion implantation of P by 5 × 10 5.¹⁴cm^-2The source / drain regions were formed so as to obtain a dose amount of. Implantation is not limited to ion implantation, but by plasma doping_xMay be injected. In addition, a stacked film of Ti and Al is used as the second conductive film 904.
[0095]
  Thereafter, the resist was patterned by a photolithography process, and these conductive films were etched into a desired shape, so that a source / drain region and a drain electrode 905 / source electrode 906 were produced. (Fig. 13D)
[0096]
  Thereafter, a protective film 908 (interlayer insulating film) was formed, and a gate electrode lead-out wiring electrode and source / drain lead-out wiring electrodes were formed, thereby completing an (N-channel) bottom gate type polysilicon thin film transistor. (FIG. 13E) Further, the protective film 908 may be formed of a silicon nitride film, a silicon oxide film, an organic resin film, or a laminated film thereof.
[0097]
  In this way, a thin film transistor was formed on the substrate to produce a panel array substrate. This thin film transistor is mainly used as a driving circuit or a switching element of a pixel.
[0098]
  Thereafter, although not shown, the pixel electrode is formed by a sputtering method or the like using a material mainly composed of Al, Ti, or the like. In this embodiment, a reflective liquid crystal display device using Al as a pixel electrode is manufactured. However, a transmissive liquid crystal display device can also be manufactured using ITO as a pixel electrode.
[0099]
  Next, an alignment film is formed on the panel array substrate and / or the counter substrate (the substrate on which the counter electrode is formed), and is heated and cured (baked). Next, a rubbing process is performed in which the substrate surface to which the alignment film is attached is rubbed in a certain direction with a buff cloth (fibers such as rayon and nylon) having a length of 2 to 3 mm to create fine grooves. In addition to rubbing treatment with a cloth or the like, the orientation treatment can be performed by an oblique vapor deposition method, a temperature gradient method, a photo-alignment method, or the like. A rubbing process is performed on either the panel array substrate or the counter substrate. In this example, the panel array substrate and the counter substrate were rubbed in order to obtain uniform liquid crystal alignment. In this case, the rubbing process is performed so as to be anti-parallel (anti-parallel) when bonded.
[0100]
  The liquid crystal panel using the panel array substrate of this embodiment performs source line inversion driving or gate line inversion driving. On the panel array substrate, thin film transistors are connected to intersections of a plurality of scanning lines provided for each row and a plurality of signal lines provided for each column. In the case of source line inversion driving, an electric field in the horizontal direction (row direction) is generated between adjacent pixels when the rubbing direction is inversion driven, so the major axis component direction of the liquid crystal molecules projected on the substrate when no electric field is applied to the scanning line Was rubbed in a direction parallel to or substantially parallel to the extending direction of. By doing so, it is possible to prevent the brightness of the reflected light from being lowered and to keep the reflectance constant regardless of the pretilt angle.
[0101]
  In addition, in the case of gate line inversion driving, an electric field in the vertical direction (column direction) is generated between adjacent pixels when the rubbing direction is inversion driven, so that the major axis component direction of liquid crystal molecules projected on the substrate when no electric field is applied The rubbing process is performed in a direction parallel or substantially parallel to the direction in which the signal line extends. By so doing, it is possible to similarly prevent a decrease in the brightness of the reflected light and to keep the reflectance constant at all times regardless of the pretilt angle.
[0102]
  In order to avoid damage to the TFT element and simplify the process, it is preferable to align the liquid crystal only by alignment treatment such as oblique vapor deposition, temperature gradient method, and photo-alignment method without performing the rubbing step. . In this alignment processing step, when source line inversion drive is performed, the alignment processing is performed so that the major axis component direction of liquid crystal molecules projected onto the substrate is parallel or substantially parallel to the direction in which the signal line extends. is important. By doing so, it is possible to prevent the brightness of reflected light from being lowered and to keep the reflectance constant at all times without depending largely on the pretilt angle.
[0103]
  The panel array substrate thus obtained is subjected to the same spacer spraying process, sealing material forming process, counter substrate bonding process, and liquid crystal injection / sealing process as in Example 1 to produce a panel.
[0104]
  Example 3
  In this embodiment, in the case of providing a protective film on the TFT of FIG. 12D in the TFT described in each of the embodiments 1 and 2 or when providing a protective film 908 (see FIG. 13E), When a silicon nitride film or an organic resin film is used as the protective film, DLC (Diamond Like C) is formed on the protective film.arbon) An example of stacking films will be described.
[0105]
  DLC is carbon having a physical property such as diamond or a material having high hardness mainly composed of carbon. Also called i-carbon, sp^ThreeIt is composed mainly of bonds.
[0106]
  Diamond is a material having the highest thermal conductivity at room temperature (about 10 to 20 W / cm · k at room temperature), and a DLC film having the same physical properties also shows a high thermal conductivity. In this embodiment, the high heat conductivity is used to function as a heat sink.
[0107]
  In addition, since the DLC film is excellent in adhesion to the organic resin film, it is a very effective material when an organic resin film is used as a protection and a heat sink is provided thereon.
[0108]
  In this embodiment, 50 sccm of methane gas and 50 sccm of hydrogen gas are introduced into the reaction space of the plasma CVD apparatus, the deposition pressure is 10 mTorr, the RF power is 100 W, and the temperature of the reaction space is room temperature. Further, a DC bias of 200 V is applied as a substrate bias, and an electric field is formed so that particles (ions) in the plasma are incident on the surface to be formed, thereby improving the film quality and improving the hardness.
[0109]
  The DLC film has very high wear resistance even when the film thickness is about 10 nm. Therefore, an effect of protecting the protective film and the TFT from mechanical impact can be obtained. This is very effective for a friction process such as a rubbing process.
[0110]
  The friction coefficient depends on the DLC film thickness, and becomes smaller as the DLC film thickness increases. Accordingly, it is sufficient that the DLC film has a thickness of 10 nm or more, but if it is too thick, the electric field applied to the liquid crystal becomes weak, so about 10 to 30 nm is preferable.
[0111]
  In addition, for more detailed film forming method and film forming apparatus of the DLC film, it is preferable to refer to Japanese Patent Publication Nos. 3-72711, 44-26900, and 42-27691 by the present inventors. .
[0112]
  In the structure obtained with the above-described structure, heat generated in the TFT is released with high efficiency, so that malfunction due to heat storage can be prevented. In particular, it is preferable to use such a heat-resistant structure for a liquid crystal display device used in a projection type electronic device.
[0113]
  Example 4
  In this embodiment, an example in which a liquid crystal display element is formed using the active matrix substrate having the TFT shown in Embodiments 1 to 3 is shown in FIG. FIG. 14 shows a portion corresponding to the main body of the liquid crystal display element, which is also called a liquid crystal module.
[0114]
  A TFT using the TFT shown in Examples 1 to 3 and using a transparent pixel electrode is called a transmissive liquid crystal display element, and a TFT using a reflective pixel electrode is called a reflective liquid crystal display element. It is out. The present invention can be applied to both liquid crystal display elements, and excellent display characteristics can be obtained.
[0115]
  In FIG. 14, reference numeral 501 denotes an active matrix substrate. A plurality of TFTs are formed on this substrate with a silicon thin film. These TFTs constitute a pixel matrix circuit 502, a gate side driving circuit 503, a source side driving circuit 504, and a logic circuit 505 on a substrate. Then, the counter substrate 506 is bonded to such an active matrix substrate. A liquid crystal layer (not shown) is sandwiched between the active matrix substrate and the counter substrate 506.
[0116]
  In the configuration shown in FIG. 14, it is desirable that the side surfaces of the active matrix substrate and the side surface of the counter substrate are all aligned except for one side. By doing so, the number of multiple chamfers from the large substrate can be increased efficiently. On the one side, a part of the counter substrate is removed to expose a part of the active matrix substrate, and an FPC (flexible printed circuit) 507 is attached thereto. Here, an IC chip (semiconductor circuit composed of MOSFETs formed on single crystal silicon) may be mounted as necessary.
[0117]
  Since the TFT constituting the circuit of this embodiment has an extremely high operation speed, a signal processing circuit driven at a high frequency of several hundred MHz to several GHz is integrally formed on the same substrate as the pixel matrix circuit. Is possible. That is, the liquid crystal module shown in FIG. 14 embodies a system-on-panel.
[0118]
  Although the present embodiment describes the case where the present invention is applied to a liquid crystal display device, an image sensor or the like provided with a photoelectric conversion layer can also be formed on the same substrate.
[0119]
  Example 5
  In this embodiment, when the present invention is applied to a liquid crystal projector, a simplified diagram of the entire apparatus including an optical system is shown in FIG. In this example, the liquid crystal panel produced using Examples 1 to 3 or the liquid crystal module of Example 4 was used. Accordingly, the apparatus configuration diagram (FIG. 3) uses a configuration substantially similar to the conventional one, but the liquid crystal panel 303 is different from the conventional one, and therefore the arrangement of the light source 301 and PBS 302 is the conventional configuration (FIG. 16 and FIG. 17). The arrangement of the light source 301 and the PBS 302 in this embodiment corresponds to the arrangement of the light source 101 and the PBS 102 in FIGS. The absolute value of the angle formed by the side direction of the exit surface of the PBS 102 that emits light from the light source 101 to the liquid crystal panel (liquid crystal display element) 103 side and the direction in which the scanning line of the liquid crystal panel extends is 45 degrees or approximately It arrange | positioned so that it might become 45 degree | times. In this way, a display having bright display characteristics can be obtained.
[0120]
  301a is a metal halide lamp and 301b is a reflector. The light source 301 is constituted by the metal halide lamps 301a and 301b. Reference numeral 305 denotes an IR filter that removes the infrared component of the light emitted from the light source 301. Reference numeral 306 denotes a homogenizer that uniformizes the light emitted from the light source 301. Reference numerals 307 and 309 denote polarizing plates. Reference numeral 302 denotes a polarization beam splitter (PBS). In this embodiment, the inclined surfaces of a pair of right-angle prisms are bonded together. A dielectric multilayer film is formed on the inclined surfaces of the pair of right-angle prisms of the PBS 302. A cross dichroic prism 308 includes a cross dichroic mirror that reflects a red spectrum and a cross dichroic mirror that reflects a green spectrum.
[0121]
  In this embodiment, reference numerals 303a, 303b, and 303c are reflection type liquid crystal panels, and those manufactured in Embodiments 1 to 4 are used. These reflective liquid crystal panels provide images corresponding to red, blue, and green, respectively. 312 is a projection lens, and 304 is a screen.
[0122]
  The operation of the liquid crystal projector using the reflective liquid crystal element according to this embodiment will be described with reference to FIG.
[0123]
  First, the light emitted from the light source 301 passes through the IR filter 305 and its infrared component is removed. The light beam that has passed through the IR filter 305 is then made uniform with respect to the exit surface by passing through the homogenizer 306 and is incident on the polarizing plate 307. The light beam incident on the polarizing plate 307 is polarized, and in this embodiment, S−Linearly polarized light having only a polarization component is emitted.
[0124]
  Next, S emitted from the polarizing plate 307−The polarized light is incident on the PBS 302. A light beam incident on the PBS 302 is branched into two linearly polarized light components whose polarization planes are orthogonal to each other at the bonding surface, and are emitted from two adjacent outer surfaces with a branch angle of exactly 90 °. In this embodiment, the light beam incident on the PBS 302 is only the S-polarized component, and the incident light beam is disposed so as to be perpendicular to the incident surface of the PBS. Therefore, the incident light beam has a branch angle of exactly 90 ° with respect to the incident surface.−The light having the polarization is emitted from the PBS, and the light having the P-polarized component is hardly emitted.
[0125]
  And S emitted from PBS−A light beam having polarized light enters the cross dichroic prism 308. Of the incident light, a light beam having a red spectral component is incident on the liquid crystal panel 303a, a light beam having a blue spectral component is incident on the liquid crystal panel 303b, and a light beam having a green spectral component is incident on the liquid crystal panel 303c. Each light beam incident on the liquid crystal panel is modulated by each liquid crystal panel, and its polarization state and intensity change. For example, S−When linearly polarized light having polarized light is incident on the liquid crystal panel and modulated, it becomes a light beam in which linearly polarized light, circularly polarized light, and elliptically polarized light are mixed.
[0126]
  Light rays having red, blue, and green spectral components modulated by the liquid crystal panel enter the cross dichroic prism 308 and enter the PBS 302 again. These rays then pass through the PBS as they pass through the PBS.−Polarization component and P−Separated into polarization components, P−Only the polarization component is incident on the polarizing plate 309.
[0127]
  P incident on the polarizing plate−The light having polarized light passes through the polarizing plate 309, and the purity of the P-polarized component is further increased. The light beam that has passed through the polarizing plate 309 enters the projection lens 312. The light emitted from the projection lens forms an image on the screen 304.
[0128]
  In this embodiment, both or one of the polarizing plates 307 and 309 may be omitted.
[0129]
  Further, the arrangement (liquid crystal panel 303, light source 301, PBS 302, screen 304, optical system, etc.) shown in FIG. 3 in this embodiment is an example, and can be appropriately changed as long as the arrangement has similar functions. Needless to say.
[0130]
  In addition, each configuration (the liquid crystal panel 303, the light source 301, the PBS 302, the screen 304, the optical system, etc.) shown in FIG. 3 in this embodiment is an example and can be appropriately changed as long as it has similar functions. Needless to say.
[0131]
  In this embodiment, a reflective liquid crystal display element is used as the liquid crystal display element, but a transmissive liquid crystal display element can also be used. When a projector is manufactured using the transmissive liquid crystal display elements manufactured in Examples 1 to 3, the arrangement direction of the polarizing plates may be appropriately changed using a conventional transmissive projector configuration.
[0132]
  Example 6
  In this embodiment, an example of an electronic apparatus (applied product) on which the electro-optical device or the semiconductor circuit shown in Embodiments 1 to 4 is mounted is shown in FIG. An electronic device is defined as a product on which a semiconductor circuit and / or an electro-optical device is mounted.
[0133]
  Electronic devices to which the present invention can be applied include video cameras, electronic still cameras, projectors, head mounted displays, car navigation systems, personal computers, personal digital assistants (mobile computers, mobile phones, PHS, etc.) and the like.
[0134]
  FIG. 15A shows a mobile computer, which includes a main body 2001, a camera portion 2002, an image receiving portion 2003, operation switches 2004, and a display device 2005. The present invention can be applied to the camera unit 2002, the image receiving unit 2003, the display device 2005, and the like.
[0135]
  FIG. 15B shows a head mounted display, which includes a main body 2101, a display device 2102, and a band portion 2103. The present invention can be applied to the display device 2102.
[0136]
  FIG. 15C illustrates a mobile phone, which includes a main body 2201, an audio output unit 2202, an audio input unit 2203, a display device 2204, operation switches 2205, and an antenna 2206. The present invention can be applied to the audio output unit 2202, the audio output unit 2203, the display device 2204, and the like.
[0137]
  FIG. 15D illustrates a video camera which includes a main body 2301, a display device 2302, an audio input portion 2303, operation switches 2304, a battery 2305, and an image receiving portion 2306. The present invention can be applied to the display device 2302, the audio input unit 2303, the image receiving unit 2306, and the like.
[0138]
  FIG. 15E illustrates a rear projector, which includes a main body 2401, a light source 2402, a display device 2403, and a polarization beam splitter.-2404, reflectors 2405 and 2406, and a screen 2407. The present invention can be applied to the display device 2403.
[0139]
  FIG. 15F illustrates a front type projector which includes a main body 2501, a light source 2502, a display device 2503, an optical system 2504, and a screen 2505. The present invention can be applied to the display device 2503.
[0140]
  As described above, the application range of the present invention is extremely wide and can be applied to electronic devices in various fields. Further, the present invention can be applied to any product that requires an electro-optical device or a semiconductor circuit.
[0141]
  In the present invention, an active matrix type liquid crystal panel is used, but other types of liquid crystal panels may be used.
[0142]
  Moreover, the arrangement of the liquid crystal panel, the light source, the PBS, the screen, the optical system, etc., shown in the TFT configurations shown in the above Examples 1 to 3 and Examples 4 and 5, is an example and has the same function. Needless to say, it can be appropriately modified.
[0143]
【The invention's effect】
  The liquid crystal electro-optical device of the present invention has a liquid crystal panel configuration in which the direction of electric lines of force generated by line inversion driving matches the alignment processing direction or rubbing processing direction of liquid crystal molecules. That is, a liquid crystal panel configuration in which the major axis component direction of the liquid crystal molecules in the absence of an electric field projected on the substrate plane is parallel or substantially parallel to the direction of the lines of electric force generated between adjacent pixel electrodes. By adopting such a configuration, it is possible to obtain brighter display characteristics than any of the conventional liquid crystal display elements of the reflective type and the transmissive type.
[0144]
  Further, when the liquid crystal electro-optical device of the present invention is applied to a projector, the side direction of the exit surface of the PBS that emits light from the light source to the liquid crystal panel side, and the row direction of the liquid crystal panel (the scanning lines of the liquid crystal panel extend) The angle between the light source and the light source is such that the light emitted from the light source is incident on the outer surface of the PBS (45 ° with respect to the dielectric multilayer coating layer on the bonding surface). The arrangement was also changed.
[0145]
  By adopting the configuration of the present invention described above, the brightness of the light, which has been a problem in the past, that is, the brightness characteristic is lowered (see FIGS. 19 to 22 and 25), the rubbing is caused, and the display quality is improved. The problem of lowering can be solved.
[0146]
  In other words, by using the technique of the present invention, it is possible to obtain an electro-optical device with good brightness characteristics and reduced disclination.
[0147]
  In addition, with the configuration of the present invention, it is possible to obtain a good display with a high luminance value of the reflected light without greatly depending on the pretilt angle. Further, even when a pretilt angle advantageous for black display (close to 90 degrees) is obtained, good brightness can be maintained, so that contrast can be improved.
[Brief description of the drawings]
FIG. 1 is an overall simplified diagram showing an embodiment of the present invention.
FIG. 2 is an overall simplified diagram showing an embodiment of the present invention.
FIG. 3 is an overall schematic diagram illustrating an embodiment when applied to a liquid crystal projector according to an embodiment 4;
FIG. 4 is a state diagram (source line inversion drive) in the direction of the lines of electric force according to the present invention.
FIG. 5 is a state diagram (gate line inversion drive) in the direction of the electric lines of force of the present invention.
[Figure 6] Three-dimensionalMuFixed conditions andMuParameters
FIG. 7 shows a three-dimensional display of the present invention (reflection type liquid crystal panel).MuIt is an example of the result figure in an evaluation. (Pretilt angle = 85 °)
[Fig. 8] Two-dimensionalMuFixed conditions andMuParameters
FIG. 9 shows a two-dimensional display in the configuration (reflection type liquid crystal panel) of the present invention.MuFIG. (Pretilt angle = 85 °)
FIG. 10 shows a two-dimensional display in the configuration (reflection type liquid crystal panel) of the present invention.MuFIG. (Pretilt angle = 87 °)
FIG. 11 shows a two-dimensional display in the configuration (reflection type liquid crystal panel) of the present invention.MuFIG. (Pretilt angle = 89 °)
12 is a drawing showing a TFT manufacturing process of the panel array substrate in Example 1. FIG.
13 is a drawing showing a TFT manufacturing process of the panel array substrate in Example 2. FIG.
14 is a diagram showing an example of a liquid crystal display element in Example 4. FIG.
FIG. 15 is a diagram illustrating an application example of the present invention.
FIG. 16 is an overall simplified view showing a conventional example.
FIG. 17 is an overall simplified view showing a conventional example.
FIG. 18 shows PBS.
FIG. 19 shows a three-dimensional display in a conventional configuration (reflection type liquid crystal panel).MuFIG. (Pretilt angle = 85 °)
FIG. 20 shows a two-dimensional display in a conventional configuration (reflection type liquid crystal panel).MuFIG. (Pretilt angle = 85 °)
FIG. 21 shows a two-dimensional display in a conventional configuration (reflection type liquid crystal panel).MuFIG. (Pretilt angle = 87 °)
FIG. 22 shows a two-dimensional display in a conventional configuration (reflection type liquid crystal panel).MuFIG. (Pretilt angle = 89 °)
FIG. 23 is a diagram showing the pretilt angle of the liquid crystal molecules and the direction of the major axis component of the liquid crystal molecules when no electric field is projected onto the substrate plane.
FIG. 24 shows a two-dimensional display in the configuration (transmission type liquid crystal panel) of the present invention.MuFIG. (Pretilt angle = 85 °)
FIG. 25 shows a two-dimensional display in a conventional configuration (transmission type liquid crystal panel).MuFIG. (Pretilt angle = 85 °)
[Explanation of symbols]
11 Light source
12 PBS
13 LCD panel
14 screens
15 S−Direction of the ray axis of polarized light
16 Rubbing direction
101 Light source
102 PBS
103 LCD panel
104 screen
110 Electric field line direction
111 rubbing direction
301 Light source
301a lamp
301b reflector-
302 PBS
303a Liquid crystal panel (R)
303b Liquid crystal panel (G)
303c Liquid crystal panel (B)
304 screens
305 IR filter
306 Homogenizer-
307, 309 Polarizing plate
308 Cross Dichroic Prism
800 substrates
801 Gate electrode
802 Gate insulating film
803 Silicon film having crystallinity
805 Source electrode
806 Drain electrode
808 Interlayer insulating film
809 Anodized film
810 channel region
811 Low concentration impurity region
812 Source region
813 Drain region
900 substrate
901 Gate electrode
902 Gate insulating film
903 Polysilicon Island
905 source electrode
906 Drain electrode
908 Protective film
909 Etching stopper
2300 substrate plane
2301 Liquid crystal molecules
2302 Pretilt angle
2303 Long axis of liquid crystal molecules (no electric field)
2304 Long-axis component direction of liquid crystal molecules projected onto a substrate plane (no electric field)
2305 Normal of substrate plane

Claims (9)

A first glass substrate comprising a plurality of scanning lines, a plurality of signal lines, a thin film transistor, a pixel electrode connected to the thin film transistor, and a first alignment film;
A second glass substrate disposed opposite to the first glass substrate and provided with a second alignment film;
A liquid crystal layer made of a vertically aligned liquid crystal material disposed between the first glass substrate and the second glass substrate;
The rubbing direction applied to the first alignment film is parallel or substantially parallel to the extending direction of the signal line ,
Electro-optical device and performs the gain Torain inversion driving. A first glass substrate comprising a plurality of scanning lines, a plurality of signal lines, a thin film transistor, a pixel electrode connected to the thin film transistor, and a first alignment film;
A second glass substrate disposed opposite to the first glass substrate and provided with a second alignment film;
A liquid crystal layer made of a vertically aligned liquid crystal material disposed between the first glass substrate and the second glass substrate;
The rubbing direction applied to the first alignment film is parallel or substantially parallel to the direction in which the scanning lines extend ,
Electro-optical device and performs Seo baselines inversion driving. A first glass substrate comprising a plurality of scanning lines, a plurality of signal lines, a thin film transistor, a pixel electrode connected to the thin film transistor, and a first alignment film;
A second glass substrate disposed opposite to the first glass substrate and provided with a second alignment film;
A liquid crystal layer made of a vertically aligned liquid crystal material disposed between the first glass substrate and the second glass substrate;
The rubbing direction applied to the second alignment film is parallel or substantially parallel to the direction in which the signal line extends ,
Electro-optical device and performs the gain Torain inversion driving. A first glass substrate comprising a plurality of scanning lines, a plurality of signal lines, a thin film transistor, a pixel electrode connected to the thin film transistor, and a first alignment film;
A second glass substrate disposed opposite to the first glass substrate and provided with a second alignment film;
A liquid crystal layer made of a vertically aligned liquid crystal material disposed between the first glass substrate and the second glass substrate;
The rubbing direction applied to the second alignment film is parallel or substantially parallel to the direction in which the scanning line extends ,
Electro-optical device and performs Seo baselines inversion driving.   5. The electro-optical device according to claim 1, wherein the pixel electrode includes a reflective metal film, a dielectric multilayer film, or a laminate thereof.   5. The electro-optical device according to claim 1, wherein the electro-optical device is a reflective liquid crystal electro-optical device. The reflective liquid crystal electro-optical device according to claim 6;
A light source that emits light to the reflective liquid crystal electro-optical device;
A polarizing beam splitter that separates light from the light source;
A cross dichroic prism disposed between the reflective liquid crystal electro-optical device and the polarization beam splitter;
Screen,
An optical unit that projects the light modulated by the reflective liquid crystal electro-optical device onto the screen;
The angle formed by the side direction of the exit surface of the polarization beam splitter that emits light from the light source to the reflective liquid crystal electro-optical device side and the direction in which the scanning line of the reflective liquid crystal electro-optical device extends Is a projection device characterized by being 43 to 47 degrees. In claim 7,
The projection apparatus is a rear type projection apparatus.   5. The electro-optical device according to claim 1, wherein the electro-optical device is a transmissive liquid crystal electro-optical device.

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