JP2009237346A - Liquid crystal device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display capable of displaying images of high contrast and of being miniaturized. <P>SOLUTION: The liquid crystal device includes: a pair of substrates (10, 20) respectively, having alignment films (16, 22) which are arranged opposite to each other; liquid crystal (50), sandwiched between the pair of substrates (10, 20) and constituted of liquid crystal molecules (501) pretilted by the alignment films; a pair of polarizing plates (310, 320), arranged so as to sandwich the pair of substrates therebetween; a first optical compensation element (210), arranged in between the pair of polarizing plates provided with positive uniaxiality and having a first optical axis inclined with respect to a direction different from a direction, in which the major axes of pretilted liquid crystal molecules are inclined from one plane along the pair of substrates as optical axis; and a second optical compensation element (220), arranged between the pair of polarizing plates having a negative refractive index ellipsoid and configured so that a slow axis generated, when a main axis of a refractive index of the negative refractive index ellipsoid is inclined from one plane is rotatable about an axis along a normal of the plane. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technical field of a liquid crystal device such as a liquid crystal light valve and an electronic apparatus such as a liquid crystal projector provided with the liquid crystal device.

  Some liquid crystal devices of this type include an optical phase difference compensation element such as a phase difference film in order to prevent the contrast from being lowered due to the phase difference (or phase shift) of light generated in the liquid crystal layer.

  With regard to such an optical phase difference compensation element, for example, in Patent Document 1, an optically anisotropic element composed of an inorganic dielectric multilayer film is tilted in accordance with the alignment direction of liquid crystal molecules with respect to a vertical alignment type liquid crystal element. Disposition techniques are disclosed.

JP 2006-11298 A

  However, for example, when the optically anisotropic element is tilted and disposed as in the technique disclosed in Patent Document 1, it is necessary to secure a space for placing the optically anisotropic element. For this reason, there is a technical problem that it is difficult to reduce the size of the liquid crystal device itself or a projector including the liquid crystal device, and the degree of freedom in layout is hindered.

  Furthermore, since the optically anisotropic element is tilted according to the alignment direction of the liquid crystal molecules, the mechanism for tilting the optically anisotropic element becomes complicated depending on the alignment direction, or additional adjustment is performed in the assembly process. There is a technical problem that may be necessary.

  The present invention has been made in view of, for example, the above-described problems. For example, a liquid crystal device capable of displaying a high-quality image with a relatively high contrast and suitable for downsizing, and such a liquid crystal device. It is an object to provide an electronic device provided.

(Liquid crystal device)
In order to solve the above problems, the liquid crystal device of the present invention is disposed opposite to each other and is sandwiched between a pair of substrates each having an alignment film and the pair of substrates, and a pretilt is caused by the alignment film. A liquid crystal composed of a liquid crystal molecule provided, a pair of polarizing plates arranged so as to sandwich the pair of substrates, and disposed between the pair of polarizing plates, and having a positive uniaxial property as an optical axis, A first optical compensation element having a first optical axis inclined in a direction different from a direction in which a major axis of the liquid crystal molecules provided with the pretilt is inclined with respect to one plane along the pair of substrates; The slow axis generated by tilting the principal axis of the negative refractive index ellipsoid with respect to the one plane has the negative refractive index ellipsoid. Along the normal of the plane And a second optical compensation element is rotatably configured about an axis.

  According to the liquid crystal device of the present invention, the pair of substrates are arranged to face each other, and the liquid crystal is sandwiched between the pair of substrates. The liquid crystal is typically a vertical alignment type liquid crystal, that is, a VA (Vertical Alignment) type liquid crystal. An alignment film is provided on each of the pair of substrates. The alignment film imparts a pretilt that rises by a predetermined angle in a predetermined direction to liquid crystal molecules constituting the liquid crystal. For example, when the liquid crystal is a VA liquid crystal, the liquid crystal molecules are aligned with a pretilt angle in a predetermined direction with respect to a normal line of one plane along the pair of substrates. For example, when the liquid crystal is a TN (Twisted Nematic) type liquid crystal, the liquid crystal molecules are aligned with a pretilt angle in a predetermined direction with respect to one plane along the pair of substrates. Such an alignment film is typically an organic alignment film that is rubbed in a predetermined direction. Alternatively, the alignment film may be an inorganic alignment film. The pair of substrates between which the liquid crystal is sandwiched is disposed so as to be sandwiched between the pair of polarizing plates. During operation of the liquid crystal device, light such as projection light is incident on the liquid crystal device, and the liquid crystal device functions as a liquid crystal light valve.

  In particular, the present invention includes first and second optical compensation elements. Each of the first and second optical compensation elements is disposed between a pair of polarizing plates. More specifically, it is disposed between one polarizing plate and a pair of substrates in a pair of polarizing plates, or between the other polarizing plate and a pair of substrates in a pair of polarizing plates. In other words, it is provided between the pair of polarizing plates and on the side on which light is incident on the pair of substrates or on the side from which light is emitted. The first optical compensation element has a positive uniaxial property, and includes, for example, a positive uniaxial crystal. The first optical axis that is the optical axis of the first optical compensation element (that is, the optical axis) is different from the direction in which the long axis of the liquid crystal molecules to which the pretilt is applied is inclined with respect to one plane along the pair of substrates. Inclined in the direction. That is, the direction in which the first optical axis is inclined with respect to one plane along the pair of substrates, and the long axis of the liquid crystal molecules at the position in contact with the alignment film when the liquid crystal device is not operating are along the pair of substrates. The directions inclined with respect to one plane are different from each other. For example, when the liquid crystal is a VA-type liquid crystal, the first optical axis is typically along a direction symmetrical to the long axis of the liquid crystal molecules to which the pretilt is applied, on one plane along the pair of substrates. . The second optical compensation element has a negative refractive index ellipsoid, and the negative refractive index ellipsoid (or the main axis of the negative refractive index ellipsoid) is inclined with respect to one plane along the pair of substrates. ing. In addition, in the second optical compensation element, a slow axis is generated due to the inclination of the negative refractive index ellipsoid. Here, the slow axis according to the present invention is a direction in which the refractive index becomes maximum when the optical anisotropy (that is, the refractive index ellipsoid) expressed three-dimensionally is cut along the one plane described above. (In other words, the direction in which the speed of light is minimized). Further, the slow axis generated in the second optical compensation element is configured to be rotatable about an axis along the normal line of one plane along the pair of substrates. Thus, for example, the second optical compensation element can be rotationally adjusted so as to cancel the phase difference of light caused by the liquid crystal and the first optical compensation element, or to finely adjust the polarization state of the light. .

  Accordingly, for example, when the liquid crystal device functioning as a liquid crystal light valve is operated, the phase difference of the light generated when the incident light passes through the liquid crystal composed of the liquid crystal molecules inclined with respect to the pair of substrates is expressed as the first phase difference. And it can compensate by the 2nd optical compensation element. That is, first, a first optical compensation element having a first optical axis tilted in a direction different from a direction in which the major axis of the liquid crystal molecules tilts is arranged for the liquid crystal composed of liquid crystal molecules given a pretilt. Thus, the refractive index ellipsoid showing the entire refractive index anisotropy of the liquid crystal and the first optical compensation element is approximated to a biaxial refractive index ellipsoid. For this reason, the first optical compensation element compensates for the phase difference caused by the tilt of the major axis of the liquid crystal molecules provided with the pretilt with respect to the normal of one plane along the pair of substrates. can do. In addition, the slow axis generated by tilting the negative index ellipsoid (or the main axis of the negative index ellipsoid) with respect to one plane can be rotated around an axis along the normal of one plane. The second optical compensation element configured as described above is disposed with respect to the liquid crystal and the first optical compensation element. The second optical compensation element is rotated and adjusted so as to cancel the phase difference between the light generated by the liquid crystal and the first optical compensation element, for example, so that the entire refractive index difference of the liquid crystal and the first and second optical compensation elements is different. The directionality can be reduced. The second optical compensation element also has a function of finely adjusting the polarization state of light.

  By performing such compensation, it is possible to prevent the light that has passed through the liquid crystal from entering the output-side polarizing plate in a state of being out of phase. Therefore, for example, in the polarizing plate on the emission side, the possibility of leakage of light that should not be transmitted is reduced, and it is possible to prevent a decrease in contrast and a reduction in viewing angle.

  Furthermore, the first and second optical compensation elements can compensate for the phase difference of the light generated in the liquid crystal without being inclined with respect to the pair of substrates. Therefore, it can be suitable for downsizing the liquid crystal device and the like.

  Each of the first and second optical compensation elements may be provided on the side where light enters the pair of substrates (in other words, the side where light enters the liquid crystal), or the pair of substrates. May be provided on the side from which light is emitted.

  Not only the VA type liquid crystal but also the TN type liquid crystal or OCB (Optically Compensated Birefringence) by appropriately setting the relationship between the first optical axis of the first optical compensation element and the slow axis of the second optical compensation element. Even with liquid crystal type liquid crystal, compensation can be performed effectively.

  As described above, according to the liquid crystal device of the present invention, the first and second optical compensation elements can compensate for the phase difference generated in the liquid crystal. Therefore, a high-definition image having a relatively high contrast can be displayed and can be suitable for downsizing.

  In one aspect of the liquid crystal device of the present invention, the second optical compensation element is formed on (i) a predetermined substrate and (ii) the predetermined substrate, and is an inorganic substance obliquely with respect to the substrate surface of the predetermined substrate. Has an inorganic film formed by being supplied.

  According to this aspect, the second optical compensation element is formed on (i) the predetermined substrate and (ii) the predetermined substrate, and the inorganic substance is supplied from an oblique direction with respect to the substrate surface of the predetermined substrate. It has the inorganic film | membrane formed by. This inorganic film is formed on the substrate surface by supplying an inorganic material such as Ta 2 O 5 from an oblique direction with respect to the substrate surface of the substrate. More specifically, as a method for forming the inorganic film, for example, an oblique deposition method or a sputtering method for supplying an inorganic substance at an atomic level along an oblique direction can be used. When viewed microscopically, the inorganic film has a film structure in which an inorganic material is grown along an oblique direction. According to such an inorganic film, anisotropy occurs in the refractive index according to the film structure of the inorganic film, and it is possible to compensate the phase of light incident on the retardation plate.

  Thereby, it is possible to effectively prevent the second optical compensation element from being deteriorated due to light irradiation and the accompanying temperature rise, and it is possible to configure a liquid crystal device having excellent reliability.

  In another aspect of the liquid crystal device of the present invention, the second optical compensation element has a negative biaxial refractive index ellipsoid as the negative refractive index ellipsoid.

  According to this aspect, the slow axis can be appropriately and easily generated by inclining the negative refractive index ellipsoid with respect to one plane.

  In another aspect of the liquid crystal device of the present invention, the second optical compensation element is rotationally adjusted so as to cancel the phase difference between the light generated by the liquid crystal and the first optical compensation element.

  According to this aspect, the second optical compensation element is rotationally adjusted so as to cancel the phase difference of the light generated by the liquid crystal and the first optical compensation element, for example, by a rotation adjustment unit provided outside the liquid crystal device. Yes. Therefore, the overall refractive index anisotropy of the liquid crystal and the first and second optical compensation elements can be further reduced.

  In another aspect of the liquid crystal device of the present invention, the second optical compensation element is configured such that the slow axis is in a state where the slow axis is along the transmission axis of one of the pair of polarizing plates. The plate is rotated and adjusted so as to adjust the polarization state of the light emitted from the polarizing plate disposed on the light incident side with respect to the pair of substrates.

  According to this aspect, first, in the second optical compensation element, the slow axis of the second optical compensation element is in a state along the transmission axis of the polarizing plate on the incident side or the outgoing side. The compensation element is rotationally adjusted so as to adjust the polarization state of the light emitted from the polarizing plate on the incident side, for example, by a rotation adjusting means provided outside the liquid crystal device. Therefore, the polarization state of light is adjusted by the second optical compensation element, and light can be incident in a more optimal polarization state on the output-side polarizing plate. Therefore, it is possible to display a higher quality image.

  In another aspect of the liquid crystal device of the present invention, the liquid crystal is a vertical alignment type liquid crystal.

  According to this aspect, the liquid crystal molecules are vertically aligned, and the pretilt imparted to the liquid crystal molecules by both of the alignment films provided on each of the pair of substrates is the same. Therefore, the phase difference of the light generated due to the long axis of the liquid crystal molecules provided with the pretilt by the two alignment films being inclined with respect to the normal line of the one plane is expressed by the first and second optical components. The compensation element can effectively compensate.

  In the aspect in which the liquid crystal is a vertical alignment type liquid crystal, the angle formed by the first optical axis with respect to the normal line of the one plane is such that the major axis of the liquid crystal molecules provided with the pretilt is the one plane. You may comprise so that it may be equal to the pretilt angle which is an angle made with respect to the normal line.

  In this case, the angle at which the first optical axis is inclined with respect to the normal of one plane along the pair of substrates (that is, the angle formed by the first optical axis and the normal) is Since it is equal to the pretilt angle, it is possible to effectively compensate for the phase difference of the light caused by the long axis of the liquid crystal molecules being inclined with respect to the normal of the one plane. Here, “equal to the pretilt angle” means that the phase difference of the light caused by the tilt of the major axis of the liquid crystal molecules is within a range sufficient to compensate to the extent allowed by the product specifications. This means that it should be close to the pretilt angle, that is, includes the case where it is substantially equal to the pretilt angle in addition to the case where it is literally equal to the pretilt angle.

  In another aspect of the liquid crystal device of the present invention, the first optical compensation element includes a positive uniaxial crystal and is formed by polishing so that the optical axis is inclined with respect to one surface. It consists of a plate.

  According to this aspect, the first optical compensation element can be configured as a crystal plate having an optical axis inclined with respect to one plane along the pair of substrates, relatively easily. Therefore, it is not necessary to dispose the first optical compensation element with respect to the one plane, and the liquid crystal device can be downsized. Here, “one surface” according to the present invention means one main surface in a flat crystal plate having two main surfaces. In the case of using quartz as the positive uniaxial crystal, for example, it is cheaper than the case of using sapphire or the like, and the processing of the crystal plate is easy. Thus, cost reduction can be achieved.

  A crystal plate whose optical axis is inclined with respect to one surface is formed by, for example, cutting a crystal by tilting it at a predetermined angle with respect to the optical axis of the crystal and polishing it to a predetermined thickness. Good. The surface opposite to the one surface is preferably polished so as to be parallel to the one surface.

  In another aspect of the liquid crystal device of the present invention, the liquid crystal device further includes a third optical compensation element having a negative uniaxial property and having a third optical axis along the normal direction of the one plane as the optical axis.

  According to this aspect, the third optical compensation element is composed of, for example, a negative uniaxial retardation plate (that is, a C plate), and the third optical axis that is the optical axis is a single one along the pair of substrates. The pair of substrates are opposed to each other so as to be along the normal direction of the plane. Therefore, the phase difference of light generated by passing through the liquid crystal can be more reliably compensated. In other words, the liquid crystal sandwiched between the pair of substrates by the first, second, and third optical compensation elements, and the refractive index anisotropy of the entire first, second, and third optical compensation elements are further increased. It can be made even smaller. That is, the refractive index ellipsoid showing the anisotropy of the entire refractive index of the liquid crystal and the first, second, and third optical compensation elements can be made closer to a sphere. Accordingly, it is possible to more reliably prevent a decrease in contrast and a reduction in viewing angle.

  In the aspect including the third optical compensation element described above, the third optical compensation element may be made of an inorganic material.

  In this case, the third optical compensation element is formed of an inorganic material using, for example, a vapor deposition method. Therefore, the third optical compensation element undergoes little or no deterioration due to ultraviolet rays or the like. Accordingly, the light resistance or durability of the third optical compensation element can be improved, and deterioration of quality over time in the display image can be reduced or prevented.

  In the aspect including the third optical compensation element described above, the optical system further includes a microlens array disposed on a light incident side with respect to the pair of substrates, and the third optical compensation element is disposed on the pair of substrates. It may be provided on the light emitting side.

  In this case, since the third optical compensation element can be arranged on the side from which the light is emitted with respect to the microlens array, the third phase difference generated when the light bent by the microlens array passes through the liquid crystal. Compensation can be ensured by the optical compensation element. In other words, the adverse effect on the phase shift of light by the microlens array can be almost or completely eliminated.

  In another aspect of the liquid crystal device of the present invention, the second optical compensation element is provided on the light incident side with respect to the pair of substrates.

  According to this aspect, when the liquid crystal device is provided in the projector as a light valve, for example, the second optical compensation element can be easily rotated and adjusted with little or no contact with other members.

  In another aspect of the liquid crystal device of the present invention, the first and second optical compensation elements are provided on the light emitting side with respect to the pair of substrates.

  According to this aspect, since the first and second optical compensation elements can be arranged on the side where light is emitted with respect to the microlens array, for example, the light bent by the microlens array passes through the liquid crystal. The generated phase difference can be reliably compensated by the first and second optical compensation elements. In other words, the adverse effect on the phase shift of light by the microlens array can be almost or completely eliminated.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described liquid crystal device according to the present invention (including various aspects thereof).

  According to the electronic apparatus of the present invention, since the above-described liquid crystal device of the present invention is provided, the phase difference generated in the light passing through the liquid crystal layer can be compensated, and high contrast can be realized. . As a result, a projection display device, television, mobile phone, electronic notebook, word processor, viewfinder type or monitor direct view type video tape recorder, workstation, video phone, Various electronic devices such as a POS terminal and a touch panel can be realized.

  Note that the electronic device of the present invention can appropriately adopt the same aspects as the various aspects of the liquid crystal device of the present invention described above.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a TFT active matrix driving type liquid crystal device with a built-in driving circuit, which is an example of the liquid crystal device of the present invention, is taken as an example.

(First embodiment)
First, a liquid crystal panel constituting the liquid crystal device according to the first embodiment will be described with reference to FIGS. The liquid crystal device according to the present embodiment is a liquid crystal device used for a light valve of a projection display device such as a liquid crystal projector. FIG. 1 is a plan view showing the configuration of the liquid crystal panel according to this embodiment, and FIG. 2 is a cross-sectional view taken along the line HH ′ of FIG. In FIGS. 1 and 2, only the liquid crystal panel is shown without the optical compensation element and the polarizing plate which will be described later in detail.

  1 and 2, in a liquid crystal panel 100 constituting the liquid crystal device according to the present embodiment, a TFT array substrate 10 and an opposing substrate 20 as an example of “a pair of substrates” according to the present invention are arranged to face each other. . A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the counter substrate 20, and the TFT array substrate 10 and the counter substrate 20 are provided with a sealing material 52 provided in a seal region positioned around the image display region 10a. Are bonded to each other.

  In FIG. 1, a light-shielding frame light-shielding film 53 that defines the frame area of the image display region 10a is provided on the counter substrate 20 side in parallel with the inside of the seal region where the sealing material 52 is disposed. A data line driving circuit 101 and an external circuit connection terminal 102 are provided along one side of the TFT array substrate 10 in a region located outside the sealing region in which the sealing material 52 is disposed in the peripheral region. The sampling circuit 7 is provided so as to be covered with the frame light shielding film 53 on the inner side of the seal region along the one side. The scanning line driving circuit 104 is provided so as to be covered with the frame light-shielding film 53 inside the seal region along two sides adjacent to the one side. On the TFT array substrate 10, vertical conduction terminals 106 for connecting the two substrates with the vertical conduction material 107 are arranged in regions facing the four corner portions of the counter substrate 20. Thus, electrical conduction can be established between the TFT array substrate 10 and the counter substrate 20.

  On the TFT array substrate 10, a lead wiring 90 is formed for electrically connecting the external circuit connection terminal 102 to the data line driving circuit 101, the scanning line driving circuit 104, the vertical conduction terminal 106, and the like. .

  In FIG. 2, on the TFT array substrate 10, a laminated structure in which wirings such as pixel switching TFTs (Thin Film Transistors), scanning lines, and data lines are formed. In the image display area 10a, pixel electrodes 9a are provided in a matrix on the upper layer of wiring such as pixel switching TFTs, scanning lines, and data lines. An alignment film 16 is formed on the pixel electrode 9a. On the other hand, a light shielding film 23 is formed on the surface of the counter substrate 20 facing the TFT array substrate 10. The light shielding film 23 is formed of, for example, a light shielding metal film or the like, and is patterned, for example, in a lattice shape in the image display region 10a on the counter substrate 20. On the light shielding film 23, a counter electrode 21 made of a transparent material such as ITO (Indium Tin Oxide) is formed in a solid shape so as to face the plurality of pixel electrodes 9a. An alignment film 22 is formed on the counter electrode 21. The liquid crystal layer 50 includes liquid crystal molecules having negative dielectric anisotropy. Therefore, the liquid crystal device according to this embodiment is a liquid crystal device in which the alignment of liquid crystal molecules is controlled in the vertical alignment (VA) mode. The liquid crystal device according to the present invention is not limited to a liquid crystal device having liquid crystal molecules having a negative dielectric anisotropy, and includes, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed. It may be a liquid crystal device that takes a predetermined alignment state between the pair of alignment films 16 and 22.

  Although not shown here, a surface of the counter substrate 20 opposite to the side facing the liquid crystal layer 50 (that is, the surface on which incident light is incident) is provided on a microlens array described later with reference to FIG. 400 is provided.

  Although not shown here, in addition to the data line driving circuit 101, the scanning line driving circuit 104, etc., on the TFT array substrate 10, in order to inspect the quality, defects, etc. of the liquid crystal device during manufacturing or at the time of shipment. An inspection circuit, an inspection pattern, or the like may be formed.

(First and second optical compensation elements and polarizing plate)
Next, the first and second optical compensation elements and the polarizing plate included in the liquid crystal device according to the present embodiment will be described with reference to FIGS.

  First, the arrangement positions of the first and second optical compensation elements and the polarizing plate will be described with reference to FIG. FIG. 3 is a cross-sectional view of the liquid crystal device according to this embodiment, showing the configuration of the liquid crystal device according to this embodiment and the incident direction of incident light. In the following drawings, detailed members of the liquid crystal panel 100 shown in FIGS. 1 and 2 are omitted as appropriate, and only directly related members are shown. 3 shows the TFT array substrate 10 and the counter substrate 20 shown in FIG. 2 upside down for convenience of explanation. In addition to FIG. 3, the X direction, Y direction, and Z direction in FIGS. 4, 7, 9, 10, and 13 to be described later are common throughout the present embodiment, and the Z direction is light. The X direction is perpendicular to the Z direction, the Y direction is perpendicular to the Z direction and the X direction, and the plane direction formed by the X direction and the Y direction is the plane direction of the polarizing glass or liquid crystal panel. . In addition, when indicating the X direction, the Y direction, or the Z direction, the direction in which the X is arranged at the center of the circle indicates the direction toward the back side of the page, and the direction in which the black circle is arranged at the center of the circle is Indicates the direction toward the front side of the page.

  In FIG. 3, the liquid crystal device according to this embodiment includes a liquid crystal panel 100, a microlens array 400, a first optical compensation element 210, a second optical compensation element 220, and polarizing plates 310 and 320. The liquid crystal panel 100, the microlens array 400, the first optical compensation element 210, and the second optical compensation element 220 are arranged so as to be sandwiched between the polarizing plates 310 and 320.

  The microlens array 400 is a microlens array plate in which microlenses corresponding to the respective pixels of the liquid crystal panel 100 are formed, and is provided between the polarizing plate 310 on the incident side and the liquid crystal panel 100. With the microlens array 400, incident light can be collected in units of pixels, and the substantial aperture ratio of the liquid crystal panel 100 can be improved. That is, the microlens array 400 can improve light use efficiency, brightness, and color purity in the liquid crystal panel 100.

  The first optical compensation element 210 and the second optical compensation element 220 are provided between the output-side polarizing plate 320 and the liquid crystal panel 100. The first optical compensation element 210 is affixed to the TFT array substrate 10. The second optical compensation element 220 is supported by a support provided separately from the TFT array substrate 10 between the first optical compensation element 210 and the output-side polarizing plate 320. It is configured to be rotatable about an axis along the normal of the surface. The first optical compensation element 210 may be configured integrally with a support provided separately from the TFT array substrate 10.

  Next, configurations of the first and second optical compensation elements and the polarizing plate will be described with reference to FIGS. 4 and 5. FIG. 4 is a perspective view of the first and second optical compensation elements and the polarizing plate according to this embodiment, and FIG. 5 is a conceptual diagram showing a method for forming the first optical compensation element according to this embodiment. is there. FIG. 4 conceptually shows the state of liquid crystal molecules in the liquid crystal panel 100 in a state where no voltage is applied, in addition to the first and second optical compensation elements and the polarizing plate. Further, in FIG. 4, for convenience of explanation, the angle α and the angle θ1 are illustrated to be larger than actual.

  In FIG. 4, the liquid crystal molecules 501 in the liquid crystal layer 50 have a predetermined orientation (see FIG. 2) in the plane of the counter substrate 20 (or the TFT array substrate 10) by the alignment films 22 and 16 (see FIG. 2) in a state where no voltage is applied. 4, the liquid crystal tilt direction 20r in the vicinity of the interface of the alignment film 22 (that is, the liquid crystal tilt direction 10r in the vicinity of the interface of the alignment film 16), which is the direction along the X direction, is a predetermined angle from the surface. A pretilt that rises only by a predetermined amount is provided, and the film is oriented while being inclined by a pretilt angle α with respect to the normal of the counter substrate 20 (or the TFT array substrate 10).

(Configuration of polarizing plate)
Each of the polarizing plates 310 and 320 is made of, for example, a polarizing film that defines the polarization of light, such as PVA (polyvinyl alcohol), and TAC (triacetyl cellulose) that is disposed on each of both surfaces of the polarizing film. It is a polarizing plate provided with the protective layer. The polarizing plate 310 is provided on the side where light enters the liquid crystal panel 100 so as to face the counter substrate 20, and the polarizing plate 320 is provided on the side where light is emitted from the liquid crystal panel 100. It is provided so as to face the array substrate 10. The polarizing plates 310 and 320 are arranged in crossed Nicols so that the transmission axis 311 of the polarizing plate 310 and the transmission axis 321 of the polarizing plate 320 are orthogonal to each other. Each of the transmission axes 311 and 321 is along a direction shifted by about 45 degrees with respect to the tilt direction 20r of the liquid crystal near the interface of the alignment film 22 (that is, the tilt direction 10r of the liquid crystal near the interface of the alignment film 16). . Since the alignment of the liquid crystal molecules 501 of the liquid crystal layer 50 is controlled in the VA mode as described above, the liquid crystal device according to the present embodiment has the image display region 10a (FIG. 1) in a state where no voltage is applied to the liquid crystal layer 50. Display the image in the normally black mode where black is displayed.

(Configuration of first optical compensation element)
The first optical compensation element 210 is made of a crystal plate formed of a positive uniaxial crystal such as quartz. The optical axis 211 of the first optical compensation element 210 is in a direction different from the direction in which the major axis of the liquid crystal molecules 501 is inclined with respect to the surface of the first optical compensation element 210 facing the liquid crystal panel 100 (ie, the XY plane). Inclined. That is, for example, when viewed in one plane orthogonal to the TFT array substrate 10 along the tilt direction 10r, the optical axis 211 is a liquid crystal molecule 501 with respect to the normal line (that is, the Z axis) of the TFT array substrate 10. The major axis is inclined by an angle θ1 in a direction different from the direction in which the major axis is inclined. Therefore, the assumed refractive index ellipsoid 212 is also inclined by an angle θ1 with respect to the normal line of the TFT array substrate 10 in a direction different from the direction in which the major axis of the liquid crystal molecules 501 is inclined. The slow axis 213 of the first optical compensation element 210 is along the tilt direction 10r of the liquid crystal near the interface of the alignment film 16 (that is, the tilt direction 20r of the liquid crystal near the interface of the alignment film 22 or the X direction). More specifically, the first optical axis 211 is symmetric with respect to the major axis of the liquid crystal molecules 501 to which the pretilt is applied with respect to the surface of the first optical compensation element 210 facing the liquid crystal panel 100 (that is, the XY plane). The angle θ1 is set to be almost equal to the pretilt angle α or completely in practice.

  As shown in FIG. 5 (a), in the present embodiment, the positive uniaxial crystal 2b is moved by an angle θ2 with respect to the optical axis L (here, the angle θ2 is a difference between 90 degrees and the angle θ1). The first optical compensation element 210 as shown in FIG. 5B is formed by cutting along the inclined cutting lines q1 and q2 and polishing to have a predetermined thickness d1. According to such a forming method, for example, when the angle θ2 is set to 85 degrees, the first optical compensation element 210 having an angle θ1 of 5 degrees (that is, an angle almost equal to the pretilt angle α) can be easily formed. . As the polishing, for example, various polishing techniques such as CMP (Chemical Mechanical Polishing) can be applied.

(Configuration of second optical compensation element)
Next, the configuration of the second optical compensation element according to the present embodiment will be described with reference to FIG. 4 described above in addition to FIGS. 7 and 8. FIG. 7 is an external perspective view schematically showing the positional relationship between the negative biaxial refractive index ellipsoid according to the present embodiment and the substrate surface (that is, the XY plane) of the TFT array substrate. FIG. 7A) is a plan view schematically showing the positional relationship between the negative biaxial refractive index ellipsoid and the substrate surface of the TFT array substrate (FIG. 7B). FIG. 8 is a cross-sectional view showing the configuration of the second optical compensation element according to the present embodiment.

  4 and 7 described above, the second optical compensation element 220 has the negative biaxial refractive index ellipsoid 222 and the direction of the principal axis ncz of the negative biaxial refractive index ellipsoid 222. Is inclined with respect to the substrate surface of the TFT array substrate 10 (that is, the XY plane). The refractive index of the negative biaxial refractive index ellipsoid 222 satisfies the following conditional expression (1).

(Refractive index ncx)> (refractive index ncy)> (refractive index ncz) (1)
In the conditional expression (1), the refractive index ncx and the refractive index ncy may be approximately equal.

  In addition, in the second optical compensation element 220, the slow axis is generated by the inclination of the main axis ncz of the negative biaxial refractive index ellipsoid 222. Here, the slow axis according to the present embodiment means a direction in which the refractive index becomes maximum when the optical anisotropy expressed three-dimensionally using a refractive index ellipsoid is cut along a predetermined plane. . Further, the slow axis generated in the second optical compensation element 220 is configured to be rotatable about an axis along the normal direction (that is, the Z direction) of the TFT array substrate 10. Typically, the direction in which the slow axis extends can be made parallel to the transmission axis of the polarizing plate. Further, the second optical compensation element 220 is disposed to face the first optical compensation element 210.

  Typically, as shown in FIG. 7A, the above-described negative biaxial refractive index ellipsoid 222 is made to have a refractive index with respect to the substrate surface of the TFT array substrate 10 (that is, the XY plane). A case of tilting with ncx as an axis will be described. In this case, as shown in the plan view of FIG. 7B, when the negative biaxial refractive index ellipsoid 222 is cut along a predetermined plane parallel to the XY plane, the direction of the refractive index ncx is the predetermined direction. Since it is included in the plane, the size when the refractive index ncx is projected onto the predetermined plane does not change. On the other hand, since the direction of the refractive index ncy in the negative biaxial refractive index ellipsoid 222 is inclined with respect to the predetermined plane, the size when the refractive index ncy is projected onto the predetermined plane. Can be made smaller than the absolute value “| ncx |” of the refractive index ncx. Note that the dotted circle in FIG. 7B indicates the size of the refractive index ncx and the refractive index ncy projected when the negative biaxial refractive index ellipsoid 222 is not inclined.

  Typically, the second optical compensation element 220 described above includes a predetermined substrate 221 and a vapor deposition film 223, as shown in FIG. The vapor deposition film 223 holds the above-described refractive index ellipsoid 222, and on a predetermined substrate so that the optical axis of the refractive index ellipsoid 222 is inclined with respect to the substrate surface (that is, the XY plane) of the TFT array substrate 10. Is obliquely deposited. Specifically, as shown in FIG. 8, the second optical compensation element 220 according to the present embodiment includes a predetermined substrate 221 made of a transparent glass substrate and the like, and an inorganic film formed on the predetermined substrate 221. 223. The inorganic film 223 is formed on the predetermined substrate 221 by depositing an inorganic substance such as Ta 2 O 5 on the predetermined substrate 221 from the vapor deposition direction D that is oblique to the predetermined substrate 221. Here, as shown in FIG. 8, the microscopic view of the inorganic film 223 includes a film structure including a portion where a column structure in which an inorganic material has grown along the vapor deposition direction D is formed. The inorganic film 223 having such a structure generates a phase difference more or less due to its fine structure. The inorganic film 223 included in the second optical compensation element 220 has a columnar portion 223a extending from the predetermined substrate 221 along the vapor deposition direction D of the inorganic substance in a cross-sectional view. Typically, the inorganic film 223 included in the second optical compensation element 220 is preferably configured to include an inorganic material. Thereby, it is possible to effectively prevent the second optical compensation element 220 from being deteriorated due to light irradiation and the accompanying temperature rise, and it is possible to configure a liquid crystal device having excellent reliability.

  In addition, as will be described in detail later, in the present embodiment, in particular, the second optical compensation element 220 is rotationally adjusted so as to cancel the phase difference of light generated by the liquid crystal layer 50 and the first optical compensation element 210. . The second optical compensation element 220 also has a function of finely adjusting the polarization state of light.

(Operation of liquid crystal device)
Next, the operation of the liquid crystal device according to this embodiment configured as described above will be described with reference to FIG. 6 in addition to FIG. 3 and FIG. FIG. 6 is a conceptual diagram conceptually showing an assumed refractive index ellipsoid obtained by synthesizing the refractive index ellipsoid of the liquid crystal layer and the refractive index ellipsoid of the first optical compensation element.

  In FIG. 3, when the liquid crystal device according to this embodiment operates, incident light first enters the polarizing plate 310 on the incident side. In the polarizing plate 310, only light that vibrates in the direction along the transmission axis 311 can pass. That is, incident light becomes linearly polarized light by passing through the polarizing plate 310. Incident light that has passed through the polarizing plate 310 passes through the microlens array 400 and the counter substrate 20 and enters the liquid crystal layer 50.

  In FIG. 4, the liquid crystal molecules 501 in the liquid crystal layer 50 are in one direction (that is, X direction) along the tilt direction 10 r with respect to the normal direction (that is, the Z direction) of the TFT array substrate 10 when no voltage is applied. It is oriented with a pretilt angle α inclined in the positive direction of the axis. Therefore, as shown in FIG. 6, the refractive index ellipsoid 501e showing the anisotropy of the refractive index of the entire liquid crystal layer 50 is also in the tilt direction 10r with respect to the normal direction (that is, the Z direction) of the TFT array substrate 10. It is inclined by a pretilt angle α in one azimuth direction (that is, a positive azimuth direction of the X axis). Therefore, if no measures are taken, the light incident on the liquid crystal layer 50 causes a phase difference due to the tilt of the refractive index ellipsoid 501e of the liquid crystal layer 50 by the pretilt angle α. The light that has passed through the layer 50 enters the output-side polarizing plate 320 with a phase shift. In addition, there is a possibility that a phase difference is caused when incident light passes through the microlens array 400 and the polarizing plates 310 and 320. For this reason, there is a possibility that light that should not pass through the polarizing plate 320 on the emission side may leak.

  However, in FIG. 4 and FIG. 6 described above, the liquid crystal device according to the present embodiment includes the first optical compensation element 210 and the second optical compensation element 220, so that incident light passes through the liquid crystal layer 50. It is possible to compensate for the phase difference of the light generated in the above. In other words, the first optical compensation element 210 and the second optical compensation element 220 can reduce the total refractive index anisotropy of the liquid crystal layer 50, the first optical compensation element 210, and the second optical compensation element 220. . That is, first, the first optical compensation having the refractive index ellipsoid 212 inclined to the opposite side of the refractive index ellipsoid 501e by the angle θ1 with respect to the liquid crystal layer 50 having the refractive index ellipsoid 501e inclined by the pretilt angle α. By disposing the element 210, the assumed refractive index ellipsoid 292 of the entire liquid crystal layer 50 and the first optical compensation element 210 is approximated to a biaxial refractive index ellipsoid. Therefore, the first optical compensation element 210 can compensate for the phase difference caused by the refractive index ellipsoid 501e of the liquid crystal layer 50 being inclined by the pretilt angle α. Further, the second optical compensation element 220 described above, that is, the negative biaxial refractive index ellipsoid 222 is included, and the main axis (or optical axis) of the negative biaxial refractive index ellipsoid 222 is the TFT array. The second optical compensation element 220 that is inclined with respect to the substrate surface (ie, the XY plane) of the substrate 10 is rotationally adjusted so as to cancel the phase difference of light generated by the liquid crystal layer 50 and the first optical compensation element 210. Therefore, the entire refractive index anisotropy of the liquid crystal layer 50, the first optical compensation element 210, and the second optical compensation element 220 can be reduced. In other words, for example, the second optical compensation element 220 is rotationally adjusted such that little or no light is emitted from the emission-side polarizing plate 320 in a state where no voltage is applied, whereby the liquid crystal layer 50 and the first optical element 220 are adjusted. The light phase difference generated by the compensation element 210 can be reliably compensated.

  By performing such compensation, it is possible to prevent the light that has passed through the liquid crystal layer 50 from entering the output-side polarizing plate 320 in a state of being out of phase. Further, since the second optical compensation element 220 also has a function of adjusting the polarization state of light, light can be incident on the exit-side polarizing plate 320 in a more optimal polarization state. Therefore, for example, in the polarizing plate 320 on the emission side, the possibility of leakage of light that should not be transmitted is reduced, and it is possible to prevent a decrease in contrast and a reduction in viewing angle.

  Furthermore, the first optical compensation element 210 and the second optical compensation element 220 compensate for the phase difference of light generated in the liquid crystal layer 50 without being inclined with respect to the TFT array substrate 10 and the counter substrate 20. Can do. Therefore, it can be suitable for downsizing the liquid crystal device and the like.

  It is desirable that the retardation (Δn · d) of the first optical compensation element 210 in the Z direction is almost or completely equal to the retardation of the liquid crystal layer 50 in the Z direction. In this case, the effect of compensating for the phase difference generated in the liquid crystal layer 50 can be further enhanced. However, even if the retardation of the first optical compensation element 210 in the Z direction is almost or completely equal to the retardation of the liquid crystal layer 50 in the Z direction, the retardation of the first optical compensation element 210 in the Z direction and the Z of the liquid crystal layer 50 are the same. The effect of compensating for the phase difference generated in the liquid crystal layer 50 can be increased correspondingly according to the difference from the retardation with respect to the direction. That is, for example, when the retardation of the liquid crystal layer 50 in the Z direction is 450 nm, the retardation of the first optical compensation element 210 is desirably 450 nm, but if the retardation is within a range of 300 nm to 500 nm, for example, The effect of compensating for the phase difference generated in the layer 50 can be reliably increased. The retardation of the second optical compensation element 220 with respect to the Z direction is preferably in the range of 10 nm to 100 nm, for example. In this case, the effect of compensating for the phase difference of light generated by the liquid crystal layer 50 and the first optical compensation element 210 can be reliably obtained by the rotation-adjusted second optical compensation element 220.

  In addition, in the present embodiment, in particular, the first optical compensation element 210 and the second optical compensation element 220 are provided on the side from which light is emitted with respect to the liquid crystal panel 100. That is, the first optical compensation element 210 and the second optical compensation element 220 are disposed on the side from which light is emitted with respect to the microlens array 400. Accordingly, the first optical compensation element 210 and the second optical compensation element 220 can reliably compensate for the phase difference generated when the light bent by the microlens array 400 passes through the liquid crystal layer 50. In other words, the adverse effect on the phase difference of light by the microlens array 400 can be almost or completely eliminated. The first optical compensation element 210 and the second optical compensation element 220 may be provided on the side where light enters the liquid crystal panel 100 (in other words, the side where light enters the liquid crystal layer 50). . Also in this case, an effect of compensating for the phase difference of light can be obtained.

  As described above, according to the liquid crystal device according to the present embodiment, the first optical compensation element 210 and the second optical compensation element 220 can compensate for the phase difference generated in the liquid crystal layer 50. Therefore, a high-definition image having a relatively high contrast can be displayed and can be suitable for downsizing.

(Second Embodiment)
A liquid crystal device according to a second embodiment will be described with reference to FIGS. FIG. 9 is a sectional view having the same concept as in FIG. 3 in the second embodiment. FIG. 10 is a perspective view having the same concept as in FIG. 4 in the second embodiment. 9 and 10, the same reference numerals are given to the same components as the components according to the first embodiment shown in FIGS. 1 to 6, and description thereof will be omitted as appropriate.

  In FIG. 9, the liquid crystal device according to the second embodiment is different from the liquid crystal device according to the first embodiment described above in that it further includes a third optical compensation element 230. Other points are the same as those in the first embodiment described above. The configuration is almost the same as that of the liquid crystal device according to the embodiment.

  9, the liquid crystal device according to the second embodiment includes a liquid crystal panel 100, a microlens array 400, a first optical compensation element 210, a second optical compensation element 220, a third optical compensation element 230, and polarizing plates 310 and 320. I have.

  The third optical compensation element 230 is provided between the output-side polarizing plate 320 and the liquid crystal panel 100 (more specifically, between the first optical compensation element 210 and the second optical compensation element 220). . The first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 are the first optical compensation element 210, the third optical compensation element 230, and the second optical compensation element 220 from the side close to the liquid crystal panel 100. It is arranged in the order. Note that the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 are in the other order (for example, the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230). In this order) may be arranged from the side closer to the liquid crystal panel 100. Further, the third optical compensation element 230 may be attached to the first optical compensation element 210 or the TFT array substrate 10, or a support is provided separately from the TFT array substrate 10, and is configured integrally with the support. May be.

  In FIG. 10, the third optical compensation element 230 is composed of a negative uniaxial retardation plate (ie, C plate). The optical axis 231 of the third optical compensation element 230 has a normal direction (that is, the XY plane or the substrate surface of the TFT array substrate 10) facing the first optical compensation element 210 of the third optical compensation element 230 (that is, the substrate surface of the TFT array substrate 10). Z direction). Therefore, the refractive index ellipsoid 232 is also along the normal direction (that is, the Z direction).

  The third optical compensation element 230 configured as described above can more reliably compensate for the phase difference of light generated by passing through the liquid crystal layer 50. In other words, the liquid crystal layer 50, the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 are formed by the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230. The anisotropy of the overall refractive index can be further reduced. That is, the refractive index ellipsoid showing the anisotropy of the entire refractive index of the liquid crystal layer 50, the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 can be made closer to a sphere. it can. Accordingly, it is possible to more reliably prevent a decrease in contrast and a reduction in viewing angle.

  Particularly in the present embodiment, the third optical compensation element 230 is formed of an inorganic material using, for example, a vapor deposition method. Therefore, the third optical compensation element 230 undergoes little or no deterioration due to ultraviolet rays or the like. Therefore, the light resistance or durability of the third optical compensation element 230 can be improved, and deterioration of quality over time in the display image can be reduced or prevented.

(Examination of effects and effects in the second embodiment-Part 1)
Next, referring to FIG. 11, the first optical when the second optical compensation element according to the second embodiment is used and when the optical film is used instead of the second optical compensation element. A quantitative relationship between the angle θ2 of the compensation element and the change in contrast according to the angle θ2 will be described. FIG. 11 shows the angle θ2 and the angle θ2 of the first optical compensation element when the second optical compensation element according to this embodiment is used and when the optical film according to the comparative example is used. 6 is a graph showing a quantitative relationship with a change in contrast. Note that the vertical axis in FIG. 11 indicates the magnitude of contrast, and the horizontal axis indicates the angle θ2 of the first optical compensation element. Further, the bar graph shown in black among the two types of bar graphs in FIG. 11 corresponds to the case where the second optical compensation element according to the present embodiment is used, and among the two types of bar graphs in FIG. The bar graph hatched with corresponds to the case of a comparative example using an optical film instead of the second optical compensation element.

  In particular, in FIG. 11, the front phase difference of the second optical compensation element according to the present embodiment is 20 nm (nanometer), and the front phase difference of the optical film according to the comparative example is also approximately 20 nm. In FIG. 11, the present embodiment and the comparative example satisfy the following three common conditions. That is, these three common conditions are that the film thickness of the first optical compensation element 210 is 35 μm, the retardation (Δn · d) in the Z direction of the third optical compensation element 230 is 300 nm, and The pretilt angle α of the liquid crystal panel 100 is 5 degrees.

  According to a study by the present inventor, as shown in the black bar graph and the shaded bar graph in FIG. 11, the angle θ2 of the first optical compensation element is “0 degrees” to “8 degrees”. In the range, it is found that the contrast is larger in the case of using the second optical compensation element according to the present embodiment than in the case of using the optical film according to the comparative example at any angle. . In addition to this, the second optical compensation element according to the present embodiment typically includes an inorganic film 223 containing an inorganic material. Therefore, the second optical compensation element deteriorates due to light irradiation and accompanying temperature rise. Thus, it is possible to effectively prevent the liquid crystal device from being formed and to form a liquid crystal device with excellent reliability.

(Examination of contrast-related effects of the second embodiment-2-)
Next, referring to FIG. 12, the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 according to the second embodiment are used, and these first optical compensation elements 210 are used. The effect of the case of the comparative example in which the second optical compensation element 220 and the third optical compensation element 230 are not used will be examined by paying attention to the degree of contrast improvement and the viewing angle. FIG. 12 is a graph showing the quantitative relationship between the contrast of the second embodiment and the contrast of the comparative example (FIG. 12A), and the viewing angle characteristic diagram of the liquid crystal device according to the comparative example (FIG. 12). 12 (b)) and a viewing angle characteristic diagram of the liquid crystal device according to the second embodiment (FIG. 12C). In addition, the vertical axis | shaft of Fig.12 (a) shows the magnitude | size of contrast. Moreover, the bar graph shown in black among the two types of bar graphs in FIG. 12A corresponds to the second embodiment, and the bar graph hatched with diagonal lines corresponds to the comparative example.

  In this simulation, the liquid crystal panel 100 has a pretilt angle α of 5 degrees and a birefringence (so-called Δn) of 0.14 as the liquid crystal layer 50, and a thickness of the liquid crystal layer 50, so-called GAP of 2 It includes a liquid crystal layer that is .7 μm. Furthermore, in this simulation, the angle θ1 at which the optical axis 211 of the first optical compensation element 210 is tilted is 5 degrees (that is, an angle equal to the pretilt angle α), and the film thickness of the first optical compensation element 210 is 35 μm. is there. The retardation of the third optical compensation element 230 in the Z direction is 300 nm. In addition, in this simulation, the front phase difference of the second optical compensation element 220 is 20 nm.

  According to this simulation, the liquid crystal device according to the second embodiment is the same as the liquid crystal device according to the comparative example, as illustrated by the black bar graph and the hatched bar graph in FIG. It has been found that the contrast is larger than that. Specifically, it has been found that the liquid crystal device according to the second embodiment has a contrast of about three times (= 3728/1291) as compared with the liquid crystal device according to the comparative example. Therefore, by providing the liquid crystal panel 100 with the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230, it is possible to effectively increase the contrast.

  In FIG. 12B and FIG. 12C, the contrast is calculated for each polar angle (that is, the angle formed between the normal line of the display screen of the liquid crystal panel and the measurement or observation direction) at each azimuth angle. The azimuth is mapped for each polar angle. Further, the same type of region shows the same range of contrast. FIGS. 12B and 12C show that the contrast increases as the circle C and the circle C ′ having the same radius are approached. Further, the position along the direction from the center to the outer edge of the viewing angle characteristic diagram indicates the magnitude of the polar angle at the same azimuth angle. As shown in FIGS. 12B and 12C, the contrast depends on each of the azimuth angle and the polar angle.

  The liquid crystal device according to the second embodiment shown in FIG. 12C (that is, the liquid crystal device in which the first optical compensation element 210, the second optical compensation element 220, and the third optical compensation element 230 are provided to the liquid crystal panel 100. The region 700a showing high contrast in FIG. 12B is a region 700c showing high contrast in the liquid crystal device according to the comparative example shown in FIG. The area of the liquid crystal device according to the second embodiment shown in c) is wider than the area shown in the same range as the area 700a. In addition, the region 700a has a polar angle within a range of 0 to 15 degrees, which requires a relatively high contrast, particularly when the liquid crystal device is used as a liquid crystal light valve of a projector, as compared with the region 700c (see FIG. When viewed only within the circle C indicated by the broken line and the inner region of FIG. C ', the viewing angle is wide. Therefore, as shown in FIG. 12C, according to the liquid crystal device according to the second embodiment, for example, compared with the liquid crystal device according to the comparative example shown in FIG. Can be increased.

(Third embodiment)
A liquid crystal device according to a third embodiment will be described with reference to FIG. FIG. 13 is a sectional view having the same concept as in FIG. 3 in the third embodiment. In FIG. 13, the same reference numerals are used for the components according to the first embodiment shown in FIGS. 1 to 8 and the components similar to the components according to the second embodiment shown in FIGS. A description thereof will be omitted as appropriate.

  In FIG. 13, the liquid crystal device according to the third embodiment includes the second optical compensation element 220 c instead of the second optical compensation element 220 in the second embodiment described above, and the liquid crystal according to the second embodiment described above. Unlike the device, the other points are substantially the same as those of the liquid crystal device according to the second embodiment described above.

  In FIG. 13, the liquid crystal device according to the third embodiment includes a liquid crystal panel 100, a microlens array 400, a first optical compensation element 210, a second optical compensation element 220c, a third optical compensation element 230, and polarizing plates 310 and 320. I have.

  Particularly in the present embodiment, the second optical compensation element 220c is provided between the incident-side polarizing plate 310 and the liquid crystal panel 100 (more specifically, between the polarizing plate 310 and the microlens array 400). The second optical compensation element 220 in the second embodiment described above is different from the second optical compensation element 220 in the second embodiment described above, and the other points are configured in substantially the same manner as the second optical compensation element 220 in the second embodiment described above.

  Therefore, when the liquid crystal device is provided in the projector as a light valve, for example, the second optical compensation element 220c can be easily rotated and adjusted with little or no contact with other members.

(Electronics)
Next, an example of an electronic device using the liquid crystal device described above will be described with reference to FIGS. The electronic apparatus according to the present embodiment is a projector that uses the liquid crystal device described above as a light valve. FIG. 14 is a plan view showing a configuration example of the projector.

  As shown in FIG. 14, a projector 1100 includes a lamp unit 1102 made of a white light source such as a halogen lamp. The projection light emitted from the lamp unit 1102 is separated into three primary colors of RGB by four mirrors 1106 and two dichroic mirrors 1108 arranged in the light guide 1104, and serves as a light valve corresponding to each primary color. The light enters the liquid crystal panels 1110R, 1110B, and 1110G.

  The configurations of the liquid crystal panels 1110R, 1110B, and 1110G have the same configuration as that of the above-described liquid crystal device, and are driven by R, G, and B primary color signals supplied from the image signal processing circuit, respectively. The light modulated by these liquid crystal panels enters the dichroic prism 1112 from three directions. In this dichroic prism 1112, R and B light is refracted at 90 degrees, while G light travels straight. Accordingly, as a result of the synthesis of the images of the respective colors, a color image is projected onto the screen or the like via the projection lens 1114.

  Here, paying attention to the display images by the liquid crystal panels 1110R, 1110B, and 1110G, the display images by the liquid crystal panels 1110R and 1110B need to be horizontally reversed with respect to the display images by the liquid crystal panel 1110G.

  Since light corresponding to the primary colors R, G, and B is incident on the liquid crystal panels 1110R, 1110B, and 1110G by the dichroic mirror 1108, it is not necessary to provide a color filter.

  Since such a projector includes the above-described liquid crystal device, the phase difference generated in the light passing through the liquid crystal layer is compensated, a high-contrast image can be displayed, and the size can be further reduced.

  In addition to the electronic device described with reference to FIG. 14, a mobile personal computer, a mobile phone, a liquid crystal television, a viewfinder type or a monitor direct view type video tape recorder, a car navigation device, a pager, and an electronic notebook , Calculators, word processors, workstations, videophones, POS terminals, devices with touch panels, and the like. Needless to say, the present invention can be applied to these various electronic devices.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. An electronic device including the liquid crystal device is also included in the technical scope of the present invention.

It is a top view of the liquid crystal panel which concerns on 1st Embodiment. It is HH 'sectional drawing of FIG. 1 is a cross-sectional view of a liquid crystal device according to a first embodiment. It is a perspective view of the 1st and 2nd optical compensation element and polarizing plate concerning a 1st embodiment. It is a conceptual diagram which shows the formation method of the 1st optical compensation element which concerns on 1st Embodiment. It is a conceptual diagram which shows notionally the assumed refractive index ellipsoid by which the assumed refractive index ellipsoid of a liquid crystal layer and the assumed refractive index ellipsoid of a 1st optical compensation element are synthesize | combined. FIG. 7A is an external perspective view schematically showing the positional relationship between the negative biaxial refractive index ellipsoid according to this embodiment and the substrate surface of the TFT array substrate (that is, the XY plane); FIG. 7B is a plan view schematically showing the positional relationship between the negative biaxial refractive index ellipsoid and the substrate surface of the TFT array substrate (FIG. 7B). It is sectional drawing which showed the structure of the 2nd optical compensation element which concerns on this embodiment. It is sectional drawing with the same meaning as FIG. 3 in 2nd Embodiment. It is a perspective view of the same meaning as FIG. 4 in 2nd Embodiment. Quantification of the angle θ2 of the first optical compensation element and the change in contrast according to the angle θ2 when the second optical compensation element according to the present embodiment is used and when the optical film according to the comparative example is used. It is the graph which showed a typical relationship. The graph (FIG. 12A) showing the quantitative relationship between the contrast of the second embodiment and the contrast of the comparative example, the viewing angle characteristic diagram of the liquid crystal device according to the comparative example (FIG. 12B), and the second FIG. 13 is a view angle characteristic diagram (FIG. 12C) of the liquid crystal device according to the second embodiment. It is sectional drawing with the same meaning as FIG. 3 in 3rd Embodiment. It is a top view which shows the structure of the projector which is an example of the electronic device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... TFT array substrate, 10r ... Tilt direction, 16 ... Alignment film, 20 ... Counter substrate, 20r ... Tilt direction, 22 ... Alignment film, 50 ... Liquid crystal layer, 100 ... Liquid crystal panel, 210 ... First optical compensation element, 220 2nd optical compensation element, 230 3rd optical compensation element, 211, 221, 231 ... Optical axis, 212, 222, 232 ... Expected refractive index ellipsoid, 213 ... Slow axis, 310, 320 ... Polarizing plate, 311 , 321 ... Transmission axis, 400 ... Microlens array.

Claims (14)

A pair of substrates disposed opposite to each other and each having an alignment film;
A liquid crystal composed of liquid crystal molecules sandwiched between the pair of substrates and provided with a pretilt by the alignment film;
A pair of polarizing plates arranged to sandwich the pair of substrates;
The long axis of the liquid crystal molecules provided with the pretilt is inclined with respect to one plane along the pair of substrates as an optical axis. A first optical compensation element having a first optical axis inclined in a direction different from the direction of
A slow axis that is disposed between the pair of polarizing plates and has a negative refractive index ellipsoid and is caused by the inclination of the main axis of the refractive index of the negative refractive index ellipsoid with respect to the one plane. A liquid crystal device comprising: a second optical compensation element configured to be rotatable about an axis along a normal line of the one plane.   The second optical compensation element is formed on (i) a predetermined substrate and (ii) the predetermined substrate, and is formed by supplying an inorganic substance from an oblique direction to the substrate surface of the predetermined substrate. The liquid crystal device according to claim 1, further comprising a film.   The liquid crystal device according to claim 1, wherein the second optical compensation element has a negative biaxial refractive index ellipsoid as the negative refractive index ellipsoid.   The rotation adjustment of the said 2nd optical compensation element is carried out so that the phase difference of the light produced by the said liquid crystal and the said 1st optical compensation element may be canceled. The liquid crystal device according to 1.   The second optical compensation element emits light from the state where the slow axis is along the transmission axis of one of the pair of polarizing plates to the pair of substrates of the pair of polarizing plates. 5. The liquid crystal device according to claim 1, wherein the liquid crystal device is rotationally adjusted so as to adjust a polarization state of light emitted from a polarizing plate disposed on a side on which light enters.   The liquid crystal device according to claim 1, wherein the liquid crystal is a vertical alignment type liquid crystal.   The angle formed by the first optical axis with respect to the normal line of the one plane is equal to the pretilt angle that is the angle formed by the long axis of the liquid crystal molecules provided with the pretilt with respect to the normal line of the one plane. The liquid crystal device according to claim 6.   2. The first optical compensation element includes a crystal plate that includes a positive uniaxial crystal and is polished so that an optical axis is inclined with respect to one surface. 8. The liquid crystal device according to any one of items 1 to 7.   9. The third optical compensation element according to claim 1, further comprising a third optical compensation element having negative uniaxiality and having a third optical axis along a normal line of the one plane as an optical axis. The liquid crystal device described.   The liquid crystal device according to claim 9, wherein the third optical compensation element is made of an inorganic material. A microlens array disposed on the light incident side of the pair of substrates;
11. The liquid crystal device according to claim 9, wherein the third optical compensation element is provided on a side from which light is emitted with respect to the pair of substrates.   12. The liquid crystal device according to claim 1, wherein the second optical compensation element is provided on a light incident side with respect to the pair of substrates.   12. The liquid crystal device according to claim 1, wherein the first and second optical compensation elements are provided on a light emitting side with respect to the pair of substrates.   An electronic apparatus comprising the liquid crystal device according to any one of claims 1 to 13.