Liquid crystal device and electronic appliance

Abstract

To provide a liquid crystal device and an electronic appliance with excellent brightness, contrast, and responsiveness.SOLUTION: A liquid crystal device includes a first substrate, a second substrate, a first liquid crystal layer disposed between the first substrate and the second substrate, a second liquid crystal layer provided between the second substrate and the first liquid crystal layer, a third substrate disposed between the first liquid crystal layer and the second liquid crystal layer, a first alignment film disposed between the first substrate and the first liquid crystal layer, a second alignment film disposed between the third substrate and the first liquid crystal layer, a third alignment film disposed between the third substrate and the second liquid crystal layer, a fourth alignment film disposed between the second substrate and the second liquid crystal layer, and a first microlens array provided on a surface of the first substrate opposite to the first liquid crystal layer. At least one of the third substrate and the first substrate includes a plurality of first pixel electrodes. The second substrate includes a plurality of second pixel electrodes. The initial alignment angle of the first liquid crystal layer by the first alignment film and the second alignment film is opposite to the initial alignment angle of the second liquid crystal layer by the third alignment film and the fourth alignment film on the basis of a reference axis.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a liquid crystal device and an electronic device. [Background technology]

[0002] In a liquid crystal display device, it is disclosed that in order to improve the contrast ratio, a first liquid crystal panel that displays a color image and a second liquid crystal panel that displays a monochrome image corresponding to the color image are overlapped (for example, see Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-139965 Summary of the Invention [Problem to be solved by the invention]

[0004] LCD panels have a problem in that there is a limit to their responsiveness due to the relationship between brightness and contrast ratio. [Means for solving the problem]

[0005] In order to achieve the above object, according to one aspect of the present invention, there is provided a liquid crystal device comprising: a first substrate, a second substrate, a first liquid crystal layer disposed between the first substrate and the second substrate, a second liquid crystal layer disposed between the second substrate and the first liquid crystal layer, a third substrate disposed between the first liquid crystal layer and the second liquid crystal layer, a first alignment film disposed between the first substrate and the first liquid crystal layer, a second alignment film disposed between the third substrate and the first liquid crystal layer, a third alignment film disposed between the third substrate and the second liquid crystal layer, a fourth alignment film disposed between the second substrate and the second liquid crystal layer, and a first microlens array provided on a surface of the first substrate opposite to the first liquid crystal layer, wherein at least one of the third substrate and the first substrate has a plurality of first pixel electrodes, and the second substrate has a plurality of second pixel electrodes, and an initial alignment angle of the first liquid crystal layer formed by the first alignment film and the second alignment film is opposite to an initial alignment angle of the second liquid crystal layer formed by the third alignment film and the fourth alignment film, with respect to a reference axis.

[0006] According to another aspect of the present invention, there is provided an electronic device including the liquid crystal device of the above aspect. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a projector as an electronic device according to an embodiment. [Figure 2] FIG. 1 is a cross-sectional view showing a schematic configuration of a liquid crystal device according to a first embodiment. [Figure 3] FIG. 4 is a diagram showing a scan clock for a first liquid crystal layer and a scan clock for a second liquid crystal layer. [Figure 4] FIG. 10 is a cross-sectional view showing a schematic configuration of a liquid crystal device according to a second embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing a modified example of the liquid crystal device according to the second embodiment. [Figure 6] FIG. 10 is a cross-sectional view showing a schematic configuration of a liquid crystal device according to a third embodiment. [Figure 7] FIG. 10 is a cross-sectional view showing a schematic configuration of a liquid crystal device according to a fourth embodiment. [Figure 8]FIG. 10 is a cross-sectional view showing a schematic configuration of a liquid crystal device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a liquid crystal device and an electronic device according to embodiments of the present invention will be described with reference to FIGS. The following embodiment shows one aspect of the present invention, does not limit the present invention, and can be modified as desired within the scope of the technical concept of the present invention. In addition, in the following drawings, the scale and number of each structure are different from the actual structure to make each configuration easier to understand.

[0009] FIG. 1 is a diagram showing a schematic configuration of a projector, which is an electronic device according to this embodiment. 1, a projector 1, which is an example of an electronic device, is a projection-type image display device that displays a color image on a screen SCR. The projector 1 includes a light source device 2, a color separation optical system 3, a light modulation device 4R, a light modulation device 4G, a light modulation device 4B, a combining optical system 5, and a projection optical device 6.

[0010] The color separation optical system 3 separates the white illumination light WL emitted from the light source device 2 into red light LR, green light LG, and blue light LB. The color separation optical system 3 includes a dichroic mirror 7a, a dichroic mirror 7b, a total reflection mirror 8a, a total reflection mirror 8b, and a total reflection mirror 8c, and a first relay lens 9a and a second relay lens 9b.

[0011] The dichroic mirror 7a separates the illumination light WL from the light source device 2 into red light LR and other light (green light LG and blue light LB). The dichroic mirror 7a transmits the red light LR and reflects the other light. The dichroic mirror 7b reflects the green light LG and transmits the blue light LB.

[0012] The total reflection mirror 8a reflects the red light LR toward the light modulation device 4R. The total reflection mirrors 8b and 8c guide the blue light LB to the light modulation device 4B. The dichroic mirror 7b guides the green light LG to the light modulation device 4G.

[0013] The first relay lens 9a is disposed between the dichroic mirror 7b and the total reflection mirror 8b in the optical path of the blue light LB, and the second relay lens 9b is disposed between the total reflection mirror 8b and the total reflection mirror 8c in the optical path of the blue light LB.

[0014] The light modulation device 4R modulates the red light LR according to image information to form red image light. The light modulation device 4G modulates the green light LG according to image information to form green image light. The light modulation device 4B modulates the blue light LB according to image information to form blue image light.

[0015] The light modulation device 4R, the light modulation device 4G, and the light modulation device 4B are, for example, transmissive liquid crystal devices 4. Furthermore, polarizing plates (not shown) are arranged on the incident side and the exit side of the liquid crystal device 4, respectively.

[0016] Furthermore, a field lens 14R, a field lens 14G, and a field lens 14B are arranged on the incident sides of the optical modulation device 4R, the optical modulation device 4G, and the optical modulation device 4B, respectively.

[0017] The image lights from the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B are incident on the combining optical system 5. The combining optical system 5 combines the image lights and emits the combined image light toward the projection optical device 6. The combining optical system 5 uses, for example, a cross dichroic prism.

[0018] The projection optical device 6 is made up of a group of projection lenses, and projects the image light combined by the combining optical system 5 onto the screen SCR in an enlarged form, thereby displaying an enlarged color image on the screen SCR.

[0019] [First embodiment of liquid crystal device] Next, a first embodiment of the liquid crystal device 4 of this embodiment will be described. In FIG. 2, the direction in which incident light L is emitted is the positive direction of the Z axis.

[0020] The liquid crystal device 4 includes a first liquid crystal panel 10, a second liquid crystal panel 20, and a first microlens array 30.

[0021] The first liquid crystal panel 10 includes a first substrate P1, a third substrate P3, and a first liquid crystal layer 11.

[0022] The first substrate P1 is located at the end of the first liquid crystal panel 10 on the -Z side. The first substrate P1 is made of a light-transmitting material such as a quartz substrate or a glass substrate. The first substrate P1 is a counter substrate. The first substrate P1 has a common electrode 12 and a first alignment film 13 on the +Z side facing the third substrate P3.

[0023] The common electrode 12 is formed on substantially the entire surface of the first substrate P1 or as a plurality of strip-shaped electrodes. The common electrode 12 is formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. The first alignment film 13 is disposed between the first substrate P1 and the first liquid crystal layer 11. The first alignment film 13 is disposed on the +Z side of the common electrode 12 and covers the common electrode 12.

[0024] The third substrate P3 is located at the end of the first liquid crystal panel 10 on the +Z side. The third substrate P3 is made of a light-transmitting material such as a quartz substrate or a glass substrate. The third substrate P3 is an element substrate. The third substrate P3 has first pixel electrodes 14 and a second alignment film 15 on the -Z side facing the first substrate P1. The first pixel electrodes 14 are electrically connected to the pixel switching elements and each of the pixel switching elements. A plurality of first pixel electrodes 14 are provided on the -Z side of the third substrate P3. The first pixel electrodes 14 are formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. The second alignment film 15 is disposed between the third substrate P3 and the first liquid crystal layer 11. The second alignment film 15 is disposed on the -Z side of the first pixel electrodes 14 and covers the first pixel electrodes 14.

[0025] The first liquid crystal layer 11 is disposed between the first substrate P1 and the second substrate P2. The first liquid crystal layer 11 is sandwiched between the first substrate P1 and the third substrate P3. The first liquid crystal layer 11 is sandwiched between a first alignment film 13 and a second alignment film 15. The first liquid crystal layer 11 includes liquid crystal molecules 11a. A first initial alignment angle θ1 of the first liquid crystal layer 11 formed by the first alignment film 13 and the second alignment film 15 is an angle at which the liquid crystal molecules 11a tilt toward one side of a direction perpendicular to a reference axis J extending in the Z-axis direction as they move toward the +Z side.

[0026] The reference axis J is, for example, a virtual axis parallel to a third direction perpendicular to the first and second directions in which the plurality of pixel electrodes provided in the liquid crystal device 4 are arranged, and is a virtual axis parallel to the normal direction of the incident surface through which light enters the liquid crystal device 4 or the exit surface through which light exits the liquid crystal device 4. The reference axis J is also a virtual axis extending in the direction in which the plurality of liquid crystal panels 10 are superimposed.

[0027] The second liquid crystal panel 20 is disposed so as to overlap the +Z side of the first liquid crystal panel 10. The second liquid crystal panel 20 has a fourth substrate P4, a second substrate P2, and a second liquid crystal layer 21.

[0028] The fourth substrate P4 is located at the end of the second liquid crystal panel 20 on the +Z side. The fourth substrate P4 is made of a light-transmitting material such as a quartz substrate or a glass substrate. The fourth substrate P4 is a counter substrate. The fourth substrate P4 has a common electrode 22 and a third alignment film 23 on the +Z side facing the second substrate P2.

[0029] The common electrode 22 is formed on substantially the entire surface of the fourth substrate P4 or as a plurality of strip-shaped electrodes. The common electrode 22 is formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. The third alignment film 23 is disposed between the third substrate P3 and the second liquid crystal layer 21. The third alignment film 23 is disposed on the +Z side of the common electrode 22 and covers the common electrode 22.

[0030] The second substrate P2 is located at the end of the second liquid crystal panel 20 on the +Z side. The second substrate P2 is made of a light-transmitting material such as a quartz substrate or a glass substrate. The second substrate P2 is an element substrate. The second substrate P2 has a second pixel electrode 24 and a fourth alignment film 25 on the -Z side facing the fourth substrate P4.

[0031] The second pixel electrodes 24 are electrically connected to the plurality of pixel switching elements and each of the plurality of pixel switching elements. A plurality of second pixel electrodes 24 are provided on the -Z side of the second substrate P2. The second pixel electrodes 24 are arranged at the same positions as the first pixel electrodes 14 so as to overlap with them in the Z direction. The second pixel electrodes 24 are formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. The fourth alignment film 25 is arranged between the second substrate P2 and the second liquid crystal layer 21. The fourth alignment film 25 is arranged on the -Z side of the second pixel electrodes 24 and covers the second pixel electrodes 24.

[0032] The first alignment film 13, the second alignment film 15, the third alignment film 23 and the fourth alignment film 25 are, for example, inorganic alignment films made of obliquely evaporated films of SiOX (x≦2), TiO2, MgO, Al2O3 or the like, and are made of a pillar structure layer in which pillar-shaped bodies called columns are formed obliquely relative to the first substrate P1, the third substrate P3, the fourth substrate P4 and the second substrate P2.

[0033] Therefore, the first alignment film 13 and the second alignment film 15 align the nematic liquid crystal molecules 11a with negative dielectric anisotropy used in the first liquid crystal layer 11 at an oblique angle with respect to the first substrate P1 and the third substrate P3. In this way, the first liquid crystal panel 10 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0034] The second liquid crystal layer 21 is provided between the second substrate P2 and the first liquid crystal layer 11. The second liquid crystal layer 21 is sandwiched between the second substrate P2 and the fourth substrate P4. The second liquid crystal layer 21 is sandwiched between a third alignment film 23 and a fourth alignment film 25. The second liquid crystal layer 21 has liquid crystal molecules 21a. A second initial alignment angle θ2 of the second liquid crystal layer 21 formed by the third alignment film 23 and the fourth alignment film 25 is an angle at which the liquid crystal molecules 21a tilt toward the other side of the direction perpendicular to the reference axis J as they move toward the +Z side.

[0035] Nematic liquid crystal molecules with negative dielectric anisotropy used in the third alignment film 23, the fourth alignment film 25, and the second liquid crystal layer 21 are aligned at an oblique angle with respect to the fourth substrate P4 and the second substrate P2. In this way, the second liquid crystal panel 20 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0036] In this embodiment, the first initial orientation angle θ1 of the first liquid crystal layer 11 formed by the first orientation film 13 and the second orientation film 15 in the first liquid crystal panel 10 is opposite to the second initial orientation angle θ2 of the second liquid crystal layer 21 formed by the third orientation film 23 and the fourth orientation film 25 in the second liquid crystal panel 20, with respect to the reference axis J.

[0037] In this embodiment, since there are two liquid crystal layers, the first liquid crystal layer 11 and the second liquid crystal layer 21, the thickness t1 of the first liquid crystal layer 11 and the thickness t2 of the second liquid crystal layer 21 can be made thinner than when there is only one liquid crystal layer.

[0038] Here, when η is the viscosity, d is the thickness of the liquid crystal layer, and K is the elastic constant, the rise time (Tr) of the first liquid crystal layer 11 and the second liquid crystal layer 21 is expressed by the following formula (1). When Δε is the dielectric anisotropy, V is the applied voltage, and Vc is the threshold voltage, the fall time (Tf) of the first liquid crystal layer 11 and the second liquid crystal layer 21 is expressed by the following formula (2).

[0039]

number

[0040]

number

[0041] As expressed by equations (1) and (2), the response speed of first liquid crystal layer 11 and second liquid crystal layer 21 is inversely proportional to the square of the thickness of the liquid crystal layer. Therefore, by reducing the thickness t1 of first liquid crystal layer 11 and the thickness t2 of second liquid crystal layer 21, respectively, the rise time (Tr) and fall time (Tf) of first liquid crystal layer 11 and second liquid crystal layer 21 can be shortened, thereby increasing the response speed.

[0042] Furthermore, by reducing the thickness t1 of the first liquid crystal layer 11 and the thickness t2 of the second liquid crystal layer 21, it is possible to reduce the driving voltage of the first liquid crystal layer 11 and the second liquid crystal layer 21, thereby suppressing the occurrence of domains in which the liquid crystal molecules 11a and the liquid crystal molecules 21a are abnormally aligned locally in the first liquid crystal layer 11 and the second liquid crystal layer 21.

[0043] Furthermore, by lowering the drive voltage, the voltage difference between adjacent pixels is reduced, which can suppress the occurrence of domains caused by the lateral electric field due to the potential difference between adjacent pixels.Furthermore, since the voltage applied between positive and negative polarities is reduced, transistor leakage and photo leakage current are also reduced, which can reduce the various costs (pre-charge function, drive frequency, power, etc.) used to prevent these leaks.

[0044] On the other hand, if the thickness t1 of the first liquid crystal layer 11 and the thickness t2 of the second liquid crystal layer 21 are each made thin, the incident light L cannot be sufficiently aligned, which may result in a decrease in brightness and a decrease in contrast. In this embodiment, the brightness and contrast can be compensated for by arranging the first liquid crystal panel 10 and the second liquid crystal panel 20, i.e., the first liquid crystal layer 11 and the second liquid crystal layer 21, overlapping in the Z-axis direction.

[0045] Furthermore, since the first initial orientation angle θ1 in the first liquid crystal panel 10 and the second initial orientation angle θ2 in the second liquid crystal panel 20 are oriented in opposite directions relative to the reference axis J, adverse effects such as light leakage of incident light L from the first liquid crystal panel 10 to the second liquid crystal panel 20 are offset, allowing the first initial orientation angle θ1 and the second initial orientation angle θ2 to be increased, preventing a decrease in the brightness of the light emitted from the second liquid crystal panel 20 and expected to improve contrast. In order to achieve the above effect, the first alignment film 13 and the second alignment film 15 intersect with the third alignment film 23 and the fourth alignment film 25 at an alignment angle greater than 90 degrees and smaller than 270 degrees.

[0046] In this embodiment, one of the first liquid crystal layer 11 and the second liquid crystal layer 21 is thinner than the other in the Z-axis direction, which is the thickness direction of the first substrate P1. In this embodiment, the thickness t1 of the first liquid crystal layer 11 is thinner than the thickness t2 of the second liquid crystal layer 21 (t1 <t2)。

[0047] In a conventional liquid crystal device using one liquid crystal panel, the thickness of the liquid crystal layer is t, and the thickness t is, for example, 2.4 μm to 3.8 μm. In this embodiment, t1+t2≦t. Considering that the minimum thickness of one liquid crystal layer is 1 μm, it is preferable that the thicknesses t1 and t2 in this embodiment are 1 μm or more and 2.8 μm or less, respectively.

[0048] By making the thickness t1 of the first liquid crystal layer 11 and the thickness t2 of the second liquid crystal layer 21 equal to or greater than 1 μm and equal to or less than 2.8 μm, respectively, the rise time (Tr) and fall time (Tf) of the first liquid crystal layer 11 and the second liquid crystal layer 21 can be shortened, thereby increasing the response speed and suppressing domains.

[0049] In this embodiment, for example, the thickness t1 is 1.0 μm and the thickness t2 is 2.0 μm. That is, the thickness t1 of the first liquid crystal layer 11 is thinner than the thickness t2 of the second liquid crystal layer 21.

[0050] FIG. 3 is a diagram showing a scan clock for the first liquid crystal layer 11 and a scan clock for the second liquid crystal layer 21. As shown in FIG.

[0051] As shown in Figure 3, in this embodiment, the duty ratios of the first liquid crystal layer 11 and the second liquid crystal layer 21 are adjusted, and as an example, the first liquid crystal layer 11 is written (scanned) n times (four times in Figure 3) as the second liquid crystal layer 21. This improves the response speed of the first liquid crystal layer 11, making it possible to generate images that require high-speed changes, particularly in moving images, and thus enabling displays that are suitable for gaming, for example. On the other hand, the response of the second liquid crystal layer 21 is slower than that of the first liquid crystal layer 11, but the contrast is improved, making it possible to generate an image in which emphasis is placed on the contrast of the background, etc. That is, the thin first liquid crystal layer 11 (first liquid crystal panel 10) plays a role in improving the response speed, and the thick second liquid crystal layer 21 (second liquid crystal panel 20) plays a role in improving the contrast.

[0052] The first microlens array 30 is provided on the surface of the first substrate P1 opposite to the first liquid crystal layer 11. The first microlens array 30 is arranged on the incident side of the first substrate P1 on which incident light L is incident. The first microlens array 30 has convex lenses 30a that bulge toward the incident side of the incident light L. As an example, one convex lens 30a is arranged for each of a plurality of pixels.

[0053] The first microlens array 30 condenses the diffused light using the arranged minute convex lenses 30a. As described above, as the depth increases in the direction in which the first liquid crystal layer 11 (first liquid crystal panel 10) and the second liquid crystal layer 21 (second liquid crystal panel 20) overlap, oblique light becomes more likely to be lost. The first microlens array 30 condenses the incident light L, so that loss of the incident light L can be suppressed.

[0054] As described above, in the liquid crystal device 4 of this embodiment, by arranging the first liquid crystal panel 10 and the second liquid crystal panel 20 so that they overlap in the Z-axis direction, it is possible to achieve excellent brightness, contrast, and responsiveness.

[0055] [Second embodiment of liquid crystal device] Next, a second embodiment of the liquid crystal device 4 will be described with reference to FIG. In this figure, the same elements as those in the first embodiment shown in FIGS. 1 to 3 are given the same reference numerals, and the description thereof will be omitted.

[0056] FIG. 4 is a cross-sectional view showing a schematic configuration of a liquid crystal device 4 according to the second embodiment. 4, the liquid crystal device 4 further includes a second microlens array 31 between the third substrate P3 and the fourth substrate P4. The second microlens array 31 has convex lenses 31a that bulge toward the third substrate P3. As an example, one convex lens 31a is arranged for each of a plurality of pixels. The other configurations are the same as those of the first embodiment.

[0057] In the liquid crystal device 4 of this embodiment, in addition to obtaining the same functions and effects as those of the first embodiment, when the refractive index of the first microlens array 30 is large, the utilization efficiency of the incident light L can be increased by providing a second microlens array 31 having convex lenses 31a.

[0058] In this embodiment, the second microlens array 31 having convex lenses 30a is provided between the third substrate P3 and the fourth substrate P4, but the present invention is not limited to this configuration. The second microlens array 31 may have concave lenses 31b as shown in FIG. This configuration is suitable when the refractive index of the first microlens array 30 is small.

[0059] [Third embodiment of liquid crystal device] Next, a third embodiment of the liquid crystal device 4 will be described with reference to FIG. In this figure, the same elements as those in the first embodiment shown in FIGS. 1 to 3 are given the same reference numerals, and the description thereof will be omitted.

[0060] FIG. 6 is a cross-sectional view showing a schematic configuration of a liquid crystal device 4 according to the third embodiment. 6, the first microlens array 30 is a cylindrical lens. The first microlens array 30 has a third microlens array 32 and a fourth microlens array 33.

[0061] The third microlens array 32 is arranged on the light incident side of the first microlens array 30 on which the incident light L is incident. The third microlens array 32 has convex lenses 32a. The fourth microlens array 33 is arranged on the first substrate P1 side of the first microlens array 30. The fourth microlens array 33 has concave lenses 33b. The fourth microlens array 33 may also have a convex lens. The other configurations are the same as those of the first embodiment.

[0062] In the liquid crystal device 4 of this embodiment, the same functions and effects as those of the first embodiment can be obtained.

[0063] [Fourth embodiment of liquid crystal device] Next, a fourth embodiment of the liquid crystal device 4 will be described with reference to FIG. In this figure, the same elements as those in the third embodiment shown in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted.

[0064] FIG. 7 is a cross-sectional view showing a schematic configuration of a liquid crystal device 4 according to the fourth embodiment. 7, the liquid crystal device 4 further includes a light path shift element 40 on the exit surface side of the second substrate P2. The light path shift element 40 is an optical member such as a glass plate.

[0065] The light path shift element 40 can be oscillated around an oscillation axis 41A extending in a direction perpendicular to the Z axis (a direction perpendicular to the plane of the paper in FIG. 7) by driving the driver 42. The light path shift element 40 can be oscillated around an oscillation axis 41B perpendicular to the Z axis and the oscillation axis 41A by driving the driver 42.

[0066] The light path shift element 40 can refract and shift the optical path of the incident light L. The light path shift element 40 shifts the optical path of the incident light L toward the pixel displayed on the screen SCR according to the posture of the light path shift element 40 swung around the swing axis 41A or the swing axis 41B. Therefore, in the liquid crystal device 4, the amount of shift in the image display position can be made smaller than one pixel, thereby increasing the apparent number of pixels. As a result, in the liquid crystal device 4, the resolution of the image projected onto the screen SCR can be increased.

[0067] In the liquid crystal device 4 of this embodiment, in addition to obtaining the same functions and effects as those of the third embodiment, the image quality is improved because the alignment speed is improved and image mixing is reduced when pixels are shifted.

[0068] [Fifth embodiment of liquid crystal device] Next, a fifth embodiment of the liquid crystal device 4 will be described with reference to FIG. In this figure, the same elements as those in the first embodiment shown in FIGS. 1 to 3 are given the same reference numerals, and the description thereof will be omitted.

[0069] The liquid crystal device 4 of this embodiment further includes a third liquid crystal panel 50. The third liquid crystal panel 50 is provided on the +Z side of the second liquid crystal panel 20 so as to overlap with it. The third liquid crystal panel 50 includes a fifth substrate P5, a sixth substrate P6, and a third liquid crystal layer 51.

[0070] The fifth substrate P5 is located at the end of the third liquid crystal panel 50 on the -Z side. The fifth substrate P5 is made of a light-transmitting material such as a quartz substrate or a glass substrate. The fifth substrate P5 is a counter substrate. The fifth substrate P5 has a common electrode 52 and a fifth alignment film 53 on the +Z side facing the sixth substrate P6.

[0071] The common electrode 52 is formed on substantially the entire surface of the common electrode 52 or as a plurality of strip-shaped electrodes. The common electrode 52 is formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. The fifth alignment film 53 is disposed between the fifth substrate P5 and the third liquid crystal layer 51. The fifth alignment film 53 is disposed on the +Z side of the common electrode 52 and covers the common electrode 52.

[0072] The sixth substrate P6 is located at the end of the first liquid crystal panel 10 on the +Z side. The sixth substrate P6 is formed of a light-transmitting material such as a quartz substrate or a glass substrate. The sixth substrate P6 is an element substrate. The sixth substrate P6 has a third pixel electrode 54 and a sixth alignment film 55 on the -Z side facing the fifth substrate P5. The third pixel electrode 54 is electrically connected to the plurality of pixel switching elements and each of the plurality of pixel switching elements. A plurality of third pixel electrodes 54 are provided on the -Z side of the sixth substrate P6. The third pixel electrodes 54 are formed of a light-transmitting conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film.

[0073] The sixth alignment film 55 is disposed between the sixth substrate P6 and the third liquid crystal layer 51. The sixth alignment film 55 is disposed on the −Z side of the third pixel electrodes , and covers the third pixel electrodes .

[0074] The third liquid crystal layer 51 is disposed between the fifth substrate P5 and the sixth substrate P6. The third liquid crystal layer 51 is sandwiched between the fifth substrate P5 and the sixth substrate P6. The third liquid crystal layer 51 is sandwiched between a fifth alignment film 53 and a sixth alignment film 55. The third liquid crystal layer 51 includes liquid crystal molecules 51a. A third initial alignment angle θ3 of the third liquid crystal layer 51 formed by the fifth alignment film 53 and the sixth alignment film 55 is an angle at which the liquid crystal molecules 51a tilt toward one side of a direction perpendicular to the reference axis J extending in the Z-axis direction as they move toward the +Z side.

[0075] The fifth alignment film 53 and the sixth alignment film 55 are, for example, inorganic alignment films made of obliquely evaporated films of SiOX (x≦2), TiO2, MgO, Al2O3, etc., and are made of a pillar structure layer in which pillar-shaped bodies called columns are formed obliquely relative to the fifth substrate P5 and the sixth substrate P6.

[0076] Therefore, the first alignment film 13 and the second alignment film 15 align the nematic liquid crystal molecules 51a with negative dielectric anisotropy used in the third liquid crystal layer 51 at an oblique angle with respect to the fifth substrate P5 and the sixth substrate P6. In this way, the third liquid crystal panel 50 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0077] In this embodiment, the second initial orientation angle θ2 of the second liquid crystal layer 21 formed by the third orientation film 23 and the fourth orientation film 25 in the second liquid crystal panel 20 is opposite to the third initial orientation angle θ3 of the third liquid crystal layer 51 formed by the fifth orientation film 53 and the sixth orientation film 55 in the third liquid crystal panel 50, with respect to the reference axis J.

[0078] In the liquid crystal device 4 having the above configuration, in addition to obtaining the same functions and effects as those of the first embodiment, the brightness and contrast of the emitted light can be improved by providing a third liquid crystal layer 51 in addition to the first liquid crystal layer 11 and the second liquid crystal layer 21. Furthermore, since the initial orientation angle θ2 in the second liquid crystal layer 21 and the initial orientation angle θ3 in the third liquid crystal layer 51 are opposite to each other with respect to the reference axis J, adverse effects such as light leakage of incident light L entering the third liquid crystal layer 51 from the second liquid crystal layer 21 are offset, allowing the respective initial orientation angles to be increased, and preventing a decrease in the brightness and contrast of the light emitted from the third liquid crystal layer 51.

[0079] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to these examples. The shapes and combinations of the components shown in the above examples are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0080] For example, in the above embodiment, the fourth substrate P4 is provided, but the present invention is not limited to this configuration. The fourth substrate P4 may not be provided, and the common electrode 22 and the third alignment film 23 may be provided on the +Z side of the third substrate P3.

[0081] In addition, in the above-described embodiment, a configuration in which a plurality of first pixel electrodes are provided on the third substrate P3 and a common electrode 12 is provided on the first substrate P1 is exemplified, but a configuration in which a plurality of first pixel electrodes are provided on the first substrate P1 and a common electrode 12 is provided on the third substrate P3 may also be used. In addition, in the above-described embodiment, a configuration in which a plurality of second pixel electrodes are provided on the fourth substrate P4 and a common electrode 22 is provided on the second substrate P2 is exemplified, but a configuration in which a plurality of second pixel electrodes are provided on the second substrate P2 and a common electrode 22 is provided on the fourth substrate P4 may also be used.

[0082] In addition, in the above-described embodiment, the first liquid crystal panel 10, the second liquid crystal panel 20, and the third liquid crystal panel 50 are configured as normally black VA (Vertical Alignment) mode liquid crystal devices, but they may also be TN (Twisted Nematic) mode liquid crystal devices.

[0083] Although the above-described embodiment has been described with reference to a projector as an example of an electronic device, the electronic device is not limited to a projector. The electronic device including the liquid crystal device may be, for example, a stereolithography device, or a device other than a projector or a stereolithography device that utilizes image light converted by the liquid crystal device.

[0084] Summary of the Disclosure A summary of this disclosure is provided below.

[0085] (Supplementary Note 1) A liquid crystal device comprising: a first substrate, a second substrate, a first liquid crystal layer disposed between the first substrate and the second substrate, a second liquid crystal layer provided between the second substrate and the first liquid crystal layer, a third substrate disposed between the first liquid crystal layer and the second liquid crystal layer, a first alignment film disposed between the first substrate and the first liquid crystal layer, a second alignment film disposed between the third substrate and the first liquid crystal layer, a third alignment film disposed between the third substrate and the second liquid crystal layer, a fourth alignment film disposed between the second substrate and the second liquid crystal layer, and a first microlens array provided on a surface of the first substrate opposite to the first liquid crystal layer, wherein the third substrate has a plurality of first pixel electrodes, and the second substrate has a plurality of second pixel electrodes, and an initial alignment angle of the first liquid crystal layer formed by the first alignment film and the second alignment film is in an opposite direction to an initial alignment angle of the second liquid crystal layer formed by the third alignment film and the fourth alignment film, with respect to a reference axis.

[0086] As described above, by thinning the first and second liquid crystal layers, the rise time (Tr) and fall time (Tf) can be shortened, resulting in a faster response speed. In addition, it is possible to lower the drive voltage for the first and second liquid crystal layers, which can suppress the formation of domains in which liquid crystal molecules are locally aligned in the first and second liquid crystal layers.

[0087] Furthermore, by stacking the first and second liquid crystal layers, brightness and contrast are compensated for. Furthermore, by having the initial alignment angles of the first and second liquid crystal layers opposite to each other with respect to the reference axis, adverse effects such as light leakage of incident light from the first liquid crystal layer to the second liquid crystal layer are offset, allowing the initial alignment angles to be increased, and reducing the reduction in brightness and contrast of light emitted from the second liquid crystal layer.

[0088] (Supplementary Note 2) The liquid crystal device according to Supplementary Note 1, wherein the thickness of the first liquid crystal layer and the thickness of the second liquid crystal layer in the thickness direction of the first substrate are 1 μm or more and 2.8 μm or less, respectively.

[0089] By adopting the configuration of Appendix 2, the total thickness of the first liquid crystal layer and the second liquid crystal layer can be made equivalent to the thickness of a conventional liquid crystal layer, and the thickness of each layer can be made thinner, thereby increasing the response speed.

[0090] (Appendix 3) A liquid crystal device according to appendix 1 or 2, wherein the first alignment film and the second alignment film intersect with the third alignment film and the fourth alignment film at an orientation angle greater than 90 degrees and less than 270 degrees.

[0091] By employing the configuration of Supplementary Note 3, it becomes possible to set the initial alignment angles of the first liquid crystal layer and the second liquid crystal layer to be opposite to each other with respect to the reference axis.

[0092] (Appendix 4) A liquid crystal device described in any one of Appendices 1 to 3, further comprising a fourth substrate disposed between the third substrate and the third alignment film, the first substrate and the third substrate being a first liquid crystal panel sandwiching the first liquid crystal layer, and the second substrate and the fourth substrate being a second liquid crystal panel sandwiching the second liquid crystal layer.

[0093] By adopting the configuration of Appendix 4, the functions and effects of Appendix 1 can be obtained by overlapping a first liquid crystal panel having a first liquid crystal layer sandwiched between a first substrate and a third substrate and a second liquid crystal panel having a second liquid crystal layer sandwiched between a second substrate and a fourth substrate.

[0094] (Appendix 5) The liquid crystal device according to any one of appendices 1 to 4, wherein one of the first liquid crystal layer and the second liquid crystal layer is thinner than the other and is written n times more than the other. By adopting the configuration of Appendix 5, one of the first and second liquid crystal layers can improve the response speed because it is thin, and the other of the first and second liquid crystal layers can improve the contrast because it is thick.

[0095] (Supplementary Note 6) The liquid crystal device according to any one of Supplementary Notes 1 to 5, wherein the first microlens array has a convex lens. By adopting the configuration of Supplementary Note 6, the loss of oblique light can be suppressed by concentrating the diffused light.

[0096] (Appendix 7) The liquid crystal device described in Appendix 6, wherein the first microlens array has a third microlens array that is a convex lens and is arranged on the light incident side, and a fourth microlens array that is arranged on the first substrate side.

[0097] By adopting the configuration of Supplementary Note 7, the combination of the third microlens array and the fourth microlens array, which are convex lenses, can condense the diffused light, thereby suppressing the loss of oblique light.

[0098] (Supplementary Note 8) The liquid crystal device according to Supplementary Note 7, wherein the fourth microlens array has a convex lens or a concave lens.

[0099] By adopting the configuration of Appendix 8, the loss of oblique light can be suppressed by concentrating diffused light by combining the third microlens array, which is a convex lens, with the fourth microlens array, which is a convex lens, or by combining the third microlens array, which is a convex lens, with the fourth microlens array, which is a concave lens.

[0100] (Supplementary Note 9) The liquid crystal device according to Supplementary Note 4, further comprising a second microlens array provided between the third substrate and the fourth substrate.

[0101] By adopting the configuration of Supplementary Note 9, the utilization efficiency of incident light can be increased by providing a second microlens array according to the magnitude of the refractive index of the first microlens array.

[0102] (Supplementary Note 10) The liquid crystal device according to Supplementary Note 9, wherein the second microlens array has a convex lens or a concave lens.

[0103] By adopting the configuration of Supplementary Note 10, when the refractive index of the first microlens array is large, the utilization efficiency of the incident light can be increased by providing a second microlens array having convex lenses. Also, when the refractive index of the first microlens array is small, the utilization efficiency of the incident light can be increased by providing a second microlens array having concave lenses.

[0104] (Supplementary Note 11) The liquid crystal device according to any one of Supplementary Notes 1 to 10, further comprising a light path shift element provided on the exit surface side of the second substrate.

[0105] By employing the configuration of Supplementary Note 11, it is possible to increase the response speed and suppress a decrease in the brightness and contrast of light when displaying an image with a higher resolution due to pixel shifting.

[0106] (Appendix 12) A liquid crystal device as described in Appendix 4, further comprising a third liquid crystal panel including a fifth substrate, a sixth substrate, and a third liquid crystal layer, wherein the third liquid crystal layer is arranged so that its initial orientation angle is in opposite directions to the initial orientation angle of the second liquid crystal layer across a reference axis.

[0107] By adopting the configuration of Supplementary Note 12, the brightness and contrast of light can be improved by providing a third liquid crystal layer in addition to the first and second liquid crystal layers. Furthermore, since the initial alignment angle in the second liquid crystal layer and the initial alignment angle in the third liquid crystal layer are opposite to each other with respect to the reference axis, adverse effects such as light leakage of incident light from the second liquid crystal layer to the third liquid crystal layer are offset, allowing the initial alignment angles to be increased and preventing a decrease in the brightness and contrast of the light emitted from the third liquid crystal layer.

[0108] (Supplementary Note 13) An electronic device comprising the liquid crystal device according to any one of Supplementary Notes 1 to 12. [Explanation of symbols]

[0109] 1...Projector (electronic device), 4...Liquid crystal device, 10...First liquid crystal panel, 11...First liquid crystal layer, 13...First alignment film, 14...First pixel electrode, 15...Second alignment film, 20...Second liquid crystal panel, 21...Second liquid crystal layer, 23...Third alignment film, 24...Second pixel electrode, 25...Fourth alignment film, 30...First microlens array, 31...Second microlens array, 32...Third microlens array, 33...Fourth microlens array, 40...Light path shift element, 50...Third liquid crystal panel, 51...Third liquid crystal layer, P1...First substrate, P2...Second substrate, P3...Third substrate, P4...Fourth substrate, P5...Fifth substrate, P6...Sixth substrate, θ1...First initial alignment angle (initial alignment angle), θ2...Second initial alignment angle (initial alignment angle)

Claims

1. a first substrate; A second substrate; a first liquid crystal layer disposed between the first substrate and the second substrate; a second liquid crystal layer provided between the second substrate and the first liquid crystal layer; a third substrate disposed between the first liquid crystal layer and the second liquid crystal layer; a first alignment film disposed between the first substrate and the first liquid crystal layer; a second alignment film disposed between the third substrate and the first liquid crystal layer; a third alignment film disposed between the third substrate and the second liquid crystal layer; a fourth alignment film disposed between the second substrate and the second liquid crystal layer; a first microlens array provided on a surface of the first substrate opposite to the first liquid crystal layer, At least one of the third substrate and the first substrate has a plurality of first pixel electrodes, and the second substrate has a plurality of second pixel electrodes; an initial alignment angle of the first liquid crystal layer formed by the first alignment film and the second alignment film is opposite to an initial alignment angle of the second liquid crystal layer formed by the third alignment film and the fourth alignment film with respect to a reference axis; A liquid crystal device characterized by:

2. In a thickness direction of the first substrate, the thickness of the first liquid crystal layer and the thickness of the second liquid crystal layer are 1 μm or more and 2.8 μm or less, respectively. The liquid crystal device according to claim 1 .

3. the first alignment film and the second alignment film intersect with the third alignment film and the fourth alignment film at an orientation angle greater than 90 degrees and smaller than 270 degrees; The liquid crystal device according to claim 1 .

4. a fourth substrate disposed between the third substrate and the third alignment film; the first substrate and the third substrate constitute a first liquid crystal panel sandwiching the first liquid crystal layer; the second substrate and the fourth substrate constitute a second liquid crystal panel sandwiching the second liquid crystal layer; The liquid crystal device according to claim 1 .

5. one of the first liquid crystal layer and the second liquid crystal layer is thinner than the other; The other n times of writing is performed. The liquid crystal device according to claim 1 .

6. The first microlens array has convex lenses. The liquid crystal device according to claim 1 .

7. The first microlens array is a third microlens array that is a convex lens and is disposed on the light incident side; a fourth microlens array disposed on the first substrate side; having The liquid crystal device according to claim 6 .

8. the fourth microlens array has convex lenses or concave lenses; The liquid crystal device according to claim 7 .

9. A second microlens array is further provided between the third substrate and the fourth substrate. The liquid crystal device according to claim 4 .

10. the second microlens array has convex lenses or concave lenses; The liquid crystal device according to claim 9 .

11. an optical path shift element is further provided on the exit surface side of the second substrate; The liquid crystal device according to claim 1 .

12. a third liquid crystal panel including a fifth substrate, a sixth substrate, and a third liquid crystal layer; the third liquid crystal layer is disposed to be superposed on the second liquid crystal layer such that an initial alignment angle thereof is opposite to an initial alignment angle of the second liquid crystal layer across a reference axis; The liquid crystal device according to claim 4 .

13. An electronic device comprising the liquid crystal device according to claim 1 .

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