Liquid crystal device and electronic apparatus

Abstract

To provide a liquid crystal device that excels in the updating rate of drawing and light amount, and an electronic apparatus.SOLUTION: A liquid crystal device comprises: a first liquid crystal unit having a first liquid crystal layer; a second liquid crystal unit having a second liquid crystal layer and located by being shifted, in a plan view, a half pixel from the first liquid crystal unit in a third direction intersecting a first direction and a second direction in which pixels are arranged in a row; and a display control circuit for supplying display data to the first and second liquid crystal units, and controls the drive of the first and second liquid crystal units. The display control circuit adopts the transmissivities of the pixels of the first liquid crystal unit and the pixels of the second liquid crystal unit in an overlapping section where the pixels of the first liquid crystal unit and the pixels of the second liquid crystal unit overlap as an average grayscale voltage of a plurality of video data pixels which one pixel of each liquid crystal unit corresponds to.SELECTED DRAWING: Figure 3

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, in order to increase the display resolution, it has been disclosed that liquid crystal panels with the same arrangement pitch are arranged in such a way that one of the liquid crystal panels is shifted in a direction intersecting the horizontal and vertical directions (see, for example, Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-35481 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventional technology, two liquid crystal panels are driven one at a time for each field, and the light from the displayed pixels is controlled so that they do not overlap at the same time, which has the problem of limiting the image update speed and light amount. [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 liquid crystal section having a first liquid crystal layer; a second liquid crystal section having a second liquid crystal layer and arranged, in a planar view, shifted by half a pixel relative to the first liquid crystal section in a third direction intersecting the first and second directions in which pixels are arranged; and a display control circuit that supplies display data to the first liquid crystal section and the second liquid crystal section and controls the driving of the first liquid crystal section and the second liquid crystal section, wherein the display control circuit sets the transmittance of the pixels of the first liquid crystal section and the pixels of the second liquid crystal section in an overlapping portion where the pixels of the first liquid crystal section and the pixels of the second liquid crystal section overlap to the voltage of the average gradation of the pixels of multiple video data corresponding to one pixel of each liquid crystal section.

[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. 3 is a schematic partial plan view showing a first pixel and a second pixel. [Figure 4] 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 5] FIG. 3 is a partially enlarged view schematically showing a first pixel and a second pixel. [Figure 6] FIG. [Figure 7] The figure is displayed in average gradation. [Figure 8] Graph showing the relationship between the total pixel voltage and the liquid crystal transmittance in the overlapping area [Figure 9] Graph showing the relationship between the total pixel voltage and the liquid crystal transmittance in the overlapping area [Figure 10] Graph showing the relationship between the total pixel voltage and the liquid crystal transmittance in the overlapping area [Figure 11] FIG. 10 is a diagram showing the brightness of overlapping pixels corrected using weighted correction values. [Figure 12] FIG. 10 is a plan view showing a schematic configuration of a liquid crystal device according to a second embodiment. [Figure 13] FIG. 10 is a side view showing a schematic configuration of a liquid crystal device according to a second embodiment. [Figure 14] FIG. 10 is a side view showing a schematic configuration of a liquid crystal device according to a third 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.

[0020] In Figure 2, the direction in which incident light L is emitted is the positive direction of the Z axis, and the direction perpendicular to the Z axis, in which pixels (described later) are arranged in a grid pattern, is the horizontal direction in a plan view as the X direction, and the vertical direction as the Y direction. The X direction corresponds to the first direction, and the Y direction corresponds to the second direction.

[0021] The liquid crystal device 4 includes a first liquid crystal portion 10A, a second liquid crystal portion 20A, a first microlens array 30, and a display control circuit 60.

[0022] The first liquid crystal section 10A is a first liquid crystal panel 10 having a first substrate P1, a second substrate P2, and a first liquid crystal layer 11.

[0023] 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 second substrate P2.

[0024] The common electrode 12 is electrically connected to the display control circuit 60. 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.

[0025] The second substrate P2 is located at the end of the first liquid crystal panel 10 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 first pixel electrode 14 and a second alignment film 15 on the -Z side facing the first substrate P1.

[0026] The first pixel electrodes 14 are electrically connected to the display control circuit 60. The first pixel electrodes 14 are electrically connected to the plurality of pixel switching elements and each of the plurality of pixel switching elements. A plurality of first pixel electrodes 14 are provided on the -Z side of the second substrate P2. 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 second substrate P2 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.

[0027] 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 second substrate P2. 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.

[0028] 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.

[0029] The second liquid crystal section 20A is a second liquid crystal panel 20 having a third substrate P3, a fourth substrate P4, and a second liquid crystal layer 21. The second liquid crystal panel 20 is disposed on the +Z side of the first liquid crystal panel 10.

[0030] The third substrate P3 is located at the end of the second liquid crystal panel 20 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 a counter substrate. The third substrate P3 has a common electrode 22 and a third alignment film 23 on the +Z side facing the fourth substrate P4.

[0031] The common electrode 22 is electrically connected to the display control circuit 60. The common electrode 22 is formed on substantially the entire surface of the third substrate P3 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.

[0032] 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 an element substrate. The fourth substrate P4 has a second pixel electrode 24 and a fourth alignment film 25 on the -Z side facing the third substrate P3.

[0033] The second pixel electrodes 24 are electrically connected to the display control circuit 60. 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 fourth substrate P4. The second pixel electrodes 24 are formed of a translucent conductive film such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film.

[0034] FIG. 3 is a schematic partial plan view showing a first pixel D formed by a first pixel electrode 14 in the first liquid crystal panel 10 and a second pixel E formed by a second pixel electrode 24 in the second liquid crystal panel 20.

[0035] For ease of understanding, the first pixels D and the second pixels E in this embodiment are squares of the same size in a plan view and are arranged in a grid pattern at a constant pitch along the X-axis and Y-axis directions. The second liquid crystal panel 20 is arranged so that the pixels are shifted by half a pixel along the W-axis, which is a third direction intersecting the X-axis and Y-axis directions.

[0036] That is, the second pixel E (second pixel electrode 24) is disposed at a position overlapping a portion of the first pixel D (first pixel electrode 14) in the Z direction. That is, for example, one first pixel D partially overlaps with four second pixels E in a planar view. Similarly, one second pixel E partially overlaps with four first pixels D in a planar view. The overlapping portion F where the first pixels D and the second pixels E partially overlap has an arrangement pitch that is half that of the first pixels D and the second pixels E, and the transmittance of the first pixels D and the second pixels E that form the overlapping portion F is supplied to the first pixel electrode 14 and the second pixel electrode 24 as a voltage of the average grayscale of the pixels of the multiple video data (display data) to which one first pixel D and one second pixel E correspond, thereby quadrupling the number of pixels.

[0037] 2, the fourth alignment film 25 is disposed between the fourth substrate P4 and the second liquid crystal layer 21. The fourth alignment film 25 is disposed on the −Z side of the second pixel electrodes 24 and covers the second pixel electrodes 24.

[0038] 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, etc., 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 second substrate P2, the third substrate P3, and the fourth substrate P4.

[0039] 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 second substrate P2. In this way, the first liquid crystal panel 10 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0040] The second liquid crystal layer 21 is disposed between the third substrate P3 and the fourth substrate P4. The second liquid crystal layer 21 is sandwiched between the third substrate P3 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 includes 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.

[0041] 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 third substrate P3 and the fourth substrate P4. In this way, the second liquid crystal panel 20 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0042] 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.

[0043] 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.

[0044] 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).

[0045]

number

[0046]

number

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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)。

[0053] 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.

[0054] 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.

[0055] 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.

[0056] FIG. 4 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.

[0057] As shown in Figure 4, in this embodiment, the duty ratio of writing to the first liquid crystal layer 11 and the second liquid crystal layer 21 is adjusted, and as an example, the first liquid crystal layer 11 is written (scanned) at n times (four times in Figure 4) the rate of 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.

[0058] 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.

[0059] 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.

[0060] The display control circuit 60 supplies display data to the first liquid crystal panel 10 and the second liquid crystal panel 20, and controls the driving of the first liquid crystal panel 10 and the second liquid crystal panel 20. The display control circuit 60 is electrically connected to the common electrode 12, the common electrode 22, the first pixel electrode 14, and the second pixel electrode 24. The display control circuit 60 sets the transmittance of the pixels of the first liquid crystal panel 10 and the second liquid crystal panel 20 in the overlapping portion of the pixels of the first liquid crystal panel 10 and the second liquid crystal panel 20 to the voltage of the average gray scale of the pixels of the multiple video data corresponding to one pixel of each of the first liquid crystal panel 10 and the second liquid crystal panel 20.

[0061] More specifically, the display control circuit 60 sets the transmittance of the first pixel D and the second pixel E that form the overlapping portion F to the voltage of the average gradation of the pixels of the multiple video data to which the first pixel D and the second pixel E correspond.

[0062] 5 is a partial enlarged view schematically illustrating one first pixel D in the first liquid crystal panel 10 and one second pixel E in the second liquid crystal panel 20 overlapping at an overlapping portion F. The first pixel D has four overlapping pixels D11, D12, D21, and D22 that overlap with four different second pixels E in the second liquid crystal panel 20 to form the overlapping portion F. The overlapping pixel D22 of the first pixel D forms the overlapping portion F with the second pixel E shown in FIG. 5. The second pixel E has four overlapping pixels E11, E12, E21, and E22 that overlap with four different first pixels D in the first liquid crystal panel 10 to form the overlapping portion F. The overlapping pixel E11 of the second pixel E forms the overlapping portion F with the first pixel D shown in FIG. 5.

[0063] The procedure for supplying display data to the first liquid crystal panel 10 and the second liquid crystal panel 20 by the display control circuit 60 based on the transmittance of the first pixel D and the second pixel E that form the overlapping portion F will be described below.

[0064] First, the display control circuit 60 obtains the average value of the brightness data of the input overlapping pixels D11, D12, D21, and D22. Based on the average value of the brightness data, the display control circuit 60 supplies a voltage of an average gray scale that determines the transmittance of the first pixel D and the second pixel E to the first liquid crystal panel 10 as display data. Similarly, the display control circuit 60 obtains the average value of the brightness data of the input overlapping pixels E11, E12, E21, and E22. Based on the average value of the brightness data, the display control circuit 60 supplies a voltage of an average gray scale that determines the transmittance of the first pixel D and the second pixel E to the second liquid crystal panel 20 as display data.

[0065] Fig. 6 shows the original image, and Fig. 7 shows the image displayed in average gradation. Here, for example, if the luminance data of one of the overlapping pixels D11, D12, D21, and D22, or one of the overlapping pixels E11, E12, E21, and E22, is significantly different from the luminance data of the other pixels, there is a possibility that the luminance will decrease significantly and the contrast will decrease, as shown in Figure 7, compared to the original image shown in Figure 6.

[0066] For example, if the luminance of overlapping pixel D22 is particularly high among overlapping pixels D11, D12, D21, and D22, then normal averaging will result in the luminance of overlapping pixel D22 being overshadowed by the luminance of the other overlapping pixels D11, D12, and D21.

[0067] Therefore, in this embodiment, the luminance of the overlapping pixels is corrected using a correction value weighted according to the number of overlapping pixels whose luminance exceeds a threshold value that is higher by a predetermined value than the average value of the luminance data.

[0068] More specifically, the display control circuit 60 first obtains the number of overlapping pixels D11, D12, D21, and D22 whose brightness exceeds the threshold. If there is one overlapping pixel whose brightness exceeds the threshold, the display control circuit 60 obtains the average brightness data value using a correction value obtained by multiplying the brightness by k1, which is greater than 1.

[0069] 8 to 10 are diagrams showing the relationship between the total pixel voltage and the liquid crystal transmittance in the overlapping portion F. For example, when the maximum voltage is applied to both the first voltage applied to the first pixel D and the second voltage applied to the second pixel E, the relationship between the first voltage applied to the first pixel D, the second voltage applied to the second pixel E, and the liquid crystal transmittance is as shown in FIG.

[0070] On the other hand, when the brightness of overlapping pixels D22 and E11 is high and the brightness of overlapping pixels D11, D12, and D21 is relatively lower than the brightness of overlapping pixels E12, E21, and E22, it is preferable to set the relationship between the first voltage applied to the first pixel D and the second voltage applied to the second pixel E and the liquid crystal transmittance as shown in Figure 9.

[0071] Furthermore, when the brightness of overlapping pixels D22 and E11 is high and the brightness of overlapping pixels D11, D12, and D21 is relatively higher than the brightness of overlapping pixels E12, E21, and E22, it is preferable to set the relationship between the first voltage applied to the first pixel D and the second voltage applied to the second pixel E and the liquid crystal transmittance to the state shown in Figure 10.

[0072] The display control circuit 60 supplies the first liquid crystal panel 10 with a voltage of an average gray level as display data using the average value obtained using the correction value, thereby increasing the average brightness in the first pixel D and achieving high contrast.

[0073] In addition, if only the brightness of the overlapping pixel D22 increases, the brightness of the overlapping pixels D11, D12, and D21 also increases, so the second voltage applied to the second pixel E that overlaps with the overlapping pixel D22 may be subtracted from the average value.

[0074] Furthermore, when there are two overlapping pixels with brightness exceeding the threshold, the average value is already large, so the display control circuit 60 obtains the average value of the brightness data using a correction value obtained by multiplying each of the two overlapping pixels with that brightness by k2, a value smaller than k1. The display control circuit 60 uses this average value to supply a voltage of the average grayscale to the first liquid crystal panel 10 as display data, thereby increasing the average brightness in the first pixel D and achieving high contrast.

[0075] Furthermore, when the number of overlapping pixels with brightness exceeding the threshold is three, the display control circuit 60 obtains the average brightness data using a correction value obtained by multiplying the brightness of one overlapping pixel that does not exceed the threshold by k1. The display control circuit 60 uses this average value to supply a voltage of the average grayscale as display data to the first liquid crystal panel 10, thereby increasing the average brightness in the first pixel D and achieving high contrast.

[0076] The procedure for obtaining the average value of the luminance data using the correction value for the first pixel D described above is also the same for the second pixel E.

[0077] FIG. 11 is a diagram showing the luminance of overlapping pixels corrected with weighted correction values. As shown in FIG. 11, by correcting the luminance of the overlapping pixels, it is possible to display a higher contrast than when displayed at the average grayscale shown in FIG.

[0078] As described above, in the liquid crystal device 4 of this embodiment, the first liquid crystal panel 10 and the second liquid crystal panel 20 are overlapped in the Z-axis direction and shifted by half a pixel in the W-axis direction, and the transmittance of the first pixel D and the second pixel E in the overlapping portion F is set to the voltage of the average gradation of the pixels of the multiple video data to which one pixel corresponds, thereby achieving excellent drawing update speed and light output.

[0079] [Second embodiment of liquid crystal device] Next, a second embodiment of the liquid crystal device 4 will be described with reference to FIGS. In these figures, the same elements as those in the first embodiment shown in FIGS. 1 to 11 are denoted by the same reference numerals, and the description thereof will be omitted.

[0080] Fig. 12 is a plan view showing a schematic configuration of a liquid crystal device 4 according to the second embodiment. Fig. 13 is a side view showing a schematic configuration of a liquid crystal device 4 according to the second embodiment. 12, the liquid crystal device 4 of this embodiment includes an actuator 70 and a drive control unit 71. The actuator 70 includes bases 72A and 72B, drive units 73A and 73B, and a friction-reducing layer 74.

[0081] In the liquid crystal device 4, the first liquid crystal panel 10 is fixed, and the second liquid crystal panel 20 is provided so as to be movable relative to the first liquid crystal panel 10 in directions around axes extending in the X-axis, Y-axis, and Z-axis directions.

[0082] The base 72A extends in the X-axis direction and is disposed on both sides of the second liquid crystal panel 20 in the Y-axis direction, at a distance from each other. The drive units 73A are disposed on both sides of the base 72A in the X-axis direction, at a distance from each other. The drive units 73A extend from the base 72A toward the second liquid crystal panel 20 and move the second liquid crystal panel 20 in the Y-axis direction. By varying the drive amounts of the two drive units 73A that are separated in the X-axis direction, the second liquid crystal panel 20 can be moved relatively around an axis extending in the Z-axis direction.

[0083] The base 72B extends in the Y-axis direction and is disposed on both sides of the second liquid crystal panel 20 in the X-axis direction, at a distance from each other. The drive units 73B are disposed on both sides of the base 72B in the Y-axis direction, at a distance from each other. The drive units 73B extend from the base 72B toward the second liquid crystal panel 20 and move the second liquid crystal panel 20 in the X-axis direction. By varying the drive amounts of the two drive units 73B that are separated in the Y-axis direction, the second liquid crystal panel 20 can be moved relatively around an axis extending in the Z-axis direction.

[0084] Examples of the drive units 73A and 73B include a screw type configuration, a configuration using magnetic repulsion, a pressure type configuration using a piezoelectric element or the like, a mechanical type configuration using a rotary motor, and an electric charge type configuration using Coulomb force.

[0085] The drive control unit 71 controls the driving of the drive units 73A and 73B. By controlling the driving of the drive units 73A and 73B, the drive control unit 71 moves the second liquid crystal panel 20 in at least one direction around an axis extending in the X-axis direction, the Y-axis direction, or the Z-axis direction. This makes it possible to easily fine-tune the relative positions of the first pixel D and the second pixel E.

[0086] 13, the friction-reducing layer 74 is provided at the joint between the first liquid crystal panel 10 and the second liquid crystal panel 20. The friction-reducing layer 74 may be made of a lubricant, for example. By providing the friction reduction layer 74 at the joint between the first liquid crystal panel 10 and the second liquid crystal panel 20, the friction force when the second liquid crystal panel 20 is moved by the driving units 73A and 73B can be reduced, making it easier to fine-tune the relative positions of the first pixel D and the second pixel E.

[0087] In the liquid crystal device 4 of this embodiment, in addition to obtaining the same functions and effects as those of the first embodiment described above, it is possible to easily fine-tune the relative positions of the first pixel D and the second pixel E even after the first liquid crystal panel 10 and the second liquid crystal panel 20 are incorporated.

[0088] In the present embodiment, the configuration in which the second liquid crystal panel 20 is moved by the actuator 70 has been exemplified, but the present invention is not limited to this configuration. The first liquid crystal panel 10 may be moved by the actuator 70, or both the first liquid crystal panel 10 and the second liquid crystal panel 20 may be moved.

[0089] [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 second embodiment shown in FIGS. 12 and 13 are denoted by the same reference numerals, and the description thereof will be omitted.

[0090] As shown in FIG. 14, the liquid crystal device 4 of this embodiment includes a first conductive transparent film 75A, a second conductive transparent film 75B, a first insulating film 76A, and a second insulating film 76B.

[0091] The first liquid crystal panel 10 has a first conductive transparent film 75A and a first insulating film 76A provided in this order facing the friction-reducing layer 74. The second liquid crystal panel 20 has a second conductive transparent film 75B and a second insulating film 76B provided in this order facing the friction-reducing layer 74. The other configurations are the same as those of the second embodiment.

[0092] In the liquid crystal device 4 having the above configuration, the drive control unit 71 applies charges of the same polarity to the first conductive transparent film 75A and the second conductive transparent film 75B when moving the second liquid crystal panel 20 using the drive units 73A and 73B to adjust the relative positions of the first liquid crystal panel 10 and the second liquid crystal panel 20. This creates a gap or reduces the pressing force between the first insulating film 76A and the friction reduction layer 74, and between the second insulating film 76B and the friction reduction layer 74, reducing the friction force when moving the second liquid crystal panel 20 and making it even easier to fine-tune the relative positions of the first pixel D and the second pixel E.

[0093] Furthermore, after adjusting the relative position by moving the second liquid crystal panel 20, the drive control section 71 applies charges of different polarities to the first conductive transparent film 75A and the second conductive transparent film 75B. As a result, the gap between the first insulating film 76A and the friction reduction layer 74, and between the second insulating film 76B and the friction reduction layer 74, is eliminated or the pressing force increases, thereby increasing the friction force and making it easy to fix the relative positions of the first pixel D and the second pixel E.

[0094] In this embodiment, the friction-reducing layer 74 is provided between the first liquid crystal panel 10 and the second liquid crystal panel 20, but the friction-reducing layer 74 may not be provided.

[0095] 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.

[0096] For example, in the above embodiment, the configuration in which the third substrate P3 is provided is exemplified, but the present invention is not limited to this configuration. For example, the third substrate P3 may not be provided, and the common electrode 22 and the third alignment film 23 may be provided on the +Z side of the second substrate P2. By adopting this configuration, the relative positions of the first liquid crystal portion 10A and the second liquid crystal portion 20A are constant, which eliminates the need for fine adjustment of the relative positions in later processes and allows the liquid crystal device 4 to be made thinner.

[0097] 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.

[0098] In addition, in the above-described embodiment, the first liquid crystal panel 10 and the second liquid crystal panel 20 are configured as normally black VA (Vertical Alignment) mode liquid crystal devices, but they may also be TN (Twisted Nematic) mode liquid crystal devices.

[0099] 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.

[0100] Summary of the Disclosure A summary of this disclosure is provided below.

[0101] (Supplementary Note 1) A liquid crystal device comprising: a first liquid crystal section having a first liquid crystal layer; a second liquid crystal section having a second liquid crystal layer and arranged, in a planar view, shifted by half a pixel from the first liquid crystal section in a third direction intersecting a first direction and a second direction in which pixels are arranged, and a display control circuit that supplies display data to the first liquid crystal section and the second liquid crystal section and controls the driving of the first liquid crystal section and the second liquid crystal section, wherein the display control circuit sets the transmittance of the pixels of the first liquid crystal section and the pixels of the second liquid crystal section in an overlapping portion where the pixels of the first liquid crystal section and the pixels of the second liquid crystal section overlap to a voltage of an average gradation of pixels of multiple video data corresponding to one pixel of each liquid crystal section.

[0102] As described above, by having separate first and second liquid crystal sections, the first and second liquid crystal layers can be made thinner, thereby shortening the rise time (Tr) and fall time (Tf), and increasing the response speed. Furthermore, it is possible to lower the driving voltage for the first and second liquid crystal layers, thereby suppressing localized liquid crystal molecules and domains of liquid crystal molecule alignment in the first and second liquid crystal layers. Furthermore, by stacking the first and second liquid crystal layers, brightness and contrast are compensated.

[0103] The transmittance of the pixels of the first liquid crystal portion and the pixels of the second liquid crystal portion that form the overlapping portion is averaged, thereby enabling the amount of light to be expressed.

[0104] (Supplementary Note 2) The liquid crystal device according to Supplementary Note 1, wherein the initial alignment angle of the first liquid crystal layer is opposite to the initial alignment angle of the second liquid crystal layer with respect to a reference axis.

[0105] By adopting the configuration of Appendix 2, adverse effects such as light leakage of incident light from the first liquid crystal layer to the second liquid crystal layer are offset, the initial orientation angles of each can be increased, and a decrease in the brightness and contrast of light emitted from the second liquid crystal layer can be suppressed.

[0106] (Appendix 3) A liquid crystal device as described in Appendix 1 or 2, wherein a first pixel of the first liquid crystal section has a plurality of overlapping pixels that each overlap with a different second pixel in the second liquid crystal section in the planar view, and the display control circuit obtains an average value of the luminance of the plurality of overlapping pixels and corrects the luminance of the overlapping pixels with a correction value corresponding to the number of overlapping pixels whose luminance exceeds a threshold that is higher by a predetermined value than the average value.

[0107] By adopting the configuration of Supplementary Note 3, even if the luminance of the overlapping pixels forming the overlapping portion is extremely high, the influence of other overlapping pixels can be mitigated, and excellent contrast can be achieved.

[0108] (Appendix 4) The liquid crystal device according to any one of appendices 1 to 3, 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.

[0109] By adopting the configuration of Appendix 4, 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.

[0110] (Appendix 5) A liquid crystal device described in any one of Appendices 1 to 4, wherein the first liquid crystal section is a first liquid crystal panel in which the first liquid crystal layer is sandwiched between a first substrate and a second substrate, and the second liquid crystal section is a second liquid crystal panel in which the second liquid crystal layer is sandwiched between a third substrate and a fourth substrate.

[0111] By adopting the configuration of Appendix 5, the first liquid crystal panel having a first liquid crystal layer sandwiched between a first substrate and a second substrate and the second liquid crystal panel having a second liquid crystal layer sandwiched between a third substrate and a fourth substrate are shifted and stacked together, thereby achieving the functions and effects of Appendix 1.

[0112] (Supplementary Note 6) The liquid crystal device according to Supplementary Note 5, further comprising: an actuator that adjusts the relative position of the first liquid crystal panel and the second liquid crystal panel; and a drive control unit that controls driving of the actuator.

[0113] By employing the configuration of Supplementary Note 6, it becomes possible to easily finely adjust the relative positions of the first pixel and the second pixel even after the first liquid crystal portion and the second liquid crystal portion are assembled.

[0114] (Supplementary Note 7) The liquid crystal device according to Supplementary Note 6, further comprising a friction-reducing layer at the joint between the first liquid crystal panel and the second liquid crystal panel.

[0115] By adopting the configuration of Supplementary Note 7, it is possible to reduce frictional force when adjusting the relative position of the first liquid crystal portion and the second liquid crystal portion, and it is possible to more easily fine-tune the relative position of the first pixel and the second pixel.

[0116] (Appendix 8) A liquid crystal device as described in Appendix 7, wherein the first liquid crystal panel has a first conductive transparent film and a first insulating film arranged in sequence opposite the friction reduction layer, and the second liquid crystal panel has a second conductive transparent film and a second insulating film arranged in sequence opposite the friction reduction layer.

[0117] By adopting the configuration of Appendix 8, by switching the polarity of the electric charge applied to the first conductive transparent film and the second conductive transparent film, respectively, it is possible to easily switch between a state in which a gap is created or the pressing force is reduced between the first liquid crystal panel and the second liquid crystal panel, and a state in which a gap is eliminated or the pressing force is increased between the first liquid crystal panel and the second liquid crystal panel.

[0118] (Appendix 9) The liquid crystal device described in Appendix 8, wherein the drive control unit applies charges of the same polarity to the first conductive transparent film and the second conductive transparent film when adjusting the relative position, and applies charges of different polarities to the first conductive transparent film and the second conductive transparent film after adjusting the relative position.

[0119] By adopting the configuration of Appendix 9, by applying charges of the same polarity to the first conductive transparent film and the second conductive transparent film, respectively, a state can be created in which a gap is created or the pressing force is reduced between the first liquid crystal panel and the second liquid crystal panel, and by applying charges of different polarities to the first conductive transparent film and the second conductive transparent film, a state can be created in which a gap is eliminated or the pressing force is increased between the first liquid crystal panel and the second liquid crystal panel.

[0120] (Supplementary Note 10) The liquid crystal device according to any one of Supplementary Notes 1 to 9, further comprising a first microlens array provided on a surface of the first liquid crystal portion opposite to the first liquid crystal layer.

[0121] By adopting the configuration of Appendix 10, diffused light can be condensed, and even when the depth in the direction in which the first liquid crystal layer and the second liquid crystal layer are stacked increases, making it easier for oblique light to be lost, the first microlens array can condense the incident light L, thereby suppressing the loss of the incident light L.

[0122] (Supplementary Note 11) An electronic device comprising the liquid crystal device according to any one of Supplementary Notes 1 to 10. [Explanation of symbols]

[0123] 1...Projector (electronic device), 4...Liquid crystal device, 10...First liquid crystal panel, 10A...First liquid crystal section, 11...First liquid crystal layer, 13...First alignment film, 14...First pixel electrode, 15...Second alignment film, 20...Second liquid crystal panel, 20A...Second liquid crystal section, 21...Second liquid crystal layer, 23...Third alignment film, 24...Second pixel electrode, 25...Fourth alignment film, 30...First microlens array, 60...Display control circuit, 70...Actuator, 71 ...Drive control unit, 75A...first conductive transparent film, 75B...second conductive transparent film, 76A...first insulating film, 76B...second insulating film, D...first pixel, D11, D12, D21, D22, E11, E12, E21, E22...overlapping pixel, E...second pixel, F...overlapping pixel, P1...first substrate, P2...second substrate, P3...third substrate, P4...fourth substrate, θ1...first initial alignment angle (initial alignment angle), θ2...second initial alignment angle (initial alignment angle)

Claims

1. a first liquid crystal portion having a first liquid crystal layer; a second liquid crystal portion having a second liquid crystal layer and being shifted by half a pixel from the first liquid crystal portion in a third direction intersecting the first and second directions in which pixels are arranged, in a plan view; a display control circuit that supplies display data to the first liquid crystal unit and the second liquid crystal unit and controls driving of the first liquid crystal unit and the second liquid crystal unit; Equipped with The display control circuit of the liquid crystal device sets the transmittance of the pixels of the first liquid crystal section and the pixels of the second liquid crystal section at the overlapping portion where the pixels of the first liquid crystal section and the pixels of the second liquid crystal section overlap to the voltage of the average gradation of the pixels of multiple video data corresponding to one pixel of each liquid crystal section.

2. an initial alignment angle of the first liquid crystal layer and an initial alignment angle of the second liquid crystal layer are opposite to each other with respect to a reference axis; The liquid crystal device according to claim 1 .

3. a first pixel of the first liquid crystal portion includes a plurality of overlapping pixels that overlap with different second pixels of the second liquid crystal portion in the plan view, The display control circuit includes: obtaining an average value of luminance values ​​of a plurality of the overlapping pixels; correcting the luminance of the overlapping pixels with a correction value according to the number of the overlapping pixels whose luminance exceeds a threshold that is higher than the average value by a predetermined value; The liquid crystal device according to claim 1 .

4. one of the first liquid crystal layer and the second liquid crystal layer is thinner than the other, and is written n times as thick as the other; The liquid crystal device according to claim 1 .

5. the first liquid crystal unit is a first liquid crystal panel in which the first liquid crystal layer is sandwiched between a first substrate and a second substrate, the second liquid crystal unit is a second liquid crystal panel in which the second liquid crystal layer is sandwiched between a third substrate and a fourth substrate; The liquid crystal device according to claim 1 .

6. an actuator that adjusts the relative positions of the first liquid crystal panel and the second liquid crystal panel; a drive control unit that controls the drive of the actuator; having The liquid crystal device according to claim 5 .

7. a friction-reducing layer is provided at a joint between the first liquid crystal panel and the second liquid crystal panel; The liquid crystal device according to claim 6 .

8. the first liquid crystal panel has a first conductive transparent film and a first insulating film that are sequentially provided opposite the friction-reducing layer; the second liquid crystal panel has a second conductive transparent film and a second insulating film, which are sequentially provided opposite the friction-reducing layer; The liquid crystal device according to claim 7 .

9. the drive control unit applies charges of the same polarity to the first conductive transparent film and the second conductive transparent film when adjusting the relative position; After adjusting the relative positions, charges of different polarities are applied to the first conductive transparent film and the second conductive transparent film. The liquid crystal device according to claim 8 .

10. a first microlens array provided on a surface of the first liquid crystal portion opposite to the first liquid crystal layer; The liquid crystal device according to claim 1 .

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

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