Liquid crystal display element and display device

Abstract

A liquid crystal display element according to the present disclosure comprises: a first substrate; a second substrate disposed facing the first substrate so as to interpose a liquid crystal layer including a plurality of liquid crystal molecules between the second substrate and the first substrate; a first electrode unit formed on an effective pixel region and a peripheral region of the effective pixel region on the first substrate; a second electrode unit having a pixel electrode unit formed on an effective pixel region on the second substrate, and a peripheral driving electrode formed on a peripheral region on the second substrate; a first alignment film formed on the effective pixel regions on each of the first substrate and the second substrate, whose alignment direction is a first azimuth angle; and a second alignment film formed on the peripheral regions on each of the first substrate and the second substrate, whose alignment direction is a second azimuth angle differing by 45° relative to the first azimuth angle.

Description

Technical Field

[0001] The present disclosure relates to a liquid crystal display element and a display device.

Background Art

[0002] In a liquid crystal display element, techniques for suppressing the influence of ionic impurities flowing into the liquid crystal layer on display characteristics have been developed (see, for example, Patent Documents 1 and 2). In Patent Document 1, a technique has been proposed in which a transverse electric field is generated by applying different driving voltages between a plurality of electrodes provided in a peripheral region of an effective pixel region, and impurity ions are moved outside the effective pixel region.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

[0004] In the above-described technology, it is conceivable that unnecessary light is generated in the peripheral region. In that case, for example, unnecessary light may be suppressed by providing a mechanical light shielding portion. However, in that case, there is a risk that light divergence of the light emitted from the effective pixel region may occur and image quality deterioration may occur.

[0005] It is desirable to provide a liquid crystal display element and a display device capable of suppressing image quality deterioration and generation of unnecessary light.

[0006] A liquid crystal display element according to one embodiment of the present disclosure comprises a first substrate, a second substrate disposed opposite to the first substrate so as to sandwich a liquid crystal layer containing a plurality of liquid crystal molecules between the first substrate and the second substrate, a second electrode portion having a first electrode portion formed in the effective pixel region of the first substrate and the peripheral region of the effective pixel region of the first substrate, a pixel electrode portion formed in the effective pixel region of the second substrate and a peripheral drive electrode portion formed in the peripheral region of the second substrate, a first alignment film formed in the effective pixel region of the first substrate and the second substrate with an alignment direction of a first azimuthal angle, and a second alignment film formed in the peripheral region of the first substrate and the second substrate with an alignment direction of a second azimuthal angle that is 45° different from the first azimuthal angle. Here, the first azimuth angle is parallel to the polarization direction of the incident light, and the second azimuth angle may be inclined at 45° with respect to the polarization direction of the incident light.

[0007] A display device according to one embodiment of the present disclosure includes a liquid crystal display element and a projection optical system for projecting an image generated by the liquid crystal display element, wherein the liquid crystal display element comprises a first substrate, a second substrate disposed opposite to the first substrate such that a liquid crystal layer containing a plurality of liquid crystal molecules is sandwiched between the first substrate and the second substrate, a second electrode portion having a first electrode portion formed in the effective pixel region of the first substrate and the peripheral region of the effective pixel region of the first substrate, a pixel electrode portion formed in the effective pixel region of the second substrate and a peripheral drive electrode portion formed in the peripheral region of the second substrate, a first alignment film formed in the effective pixel region of the first substrate and the second substrate with an orientation direction of a first azimuthal angle, and a second alignment film formed in the peripheral region of the first substrate and the second substrate with an orientation direction of a second azimuthal angle that is 45° different from the first azimuthal angle. Here, the first azimuth angle is parallel to the polarization direction of the incident light, and the second azimuth angle may be inclined at 45° with respect to the polarization direction of the incident light.

[0008] In a liquid crystal display element or display device according to one embodiment of the present disclosure, a peripheral drive electrode portion is formed in the peripheral region of the effective pixel area, and a second alignment film is formed in the peripheral region, having an azimuthal angle 45° different from that of the first alignment film formed in the effective pixel area. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view showing a first configuration example of a liquid crystal display element according to a comparative example. [Figure 2] This is a cross-sectional view showing a first configuration example of a liquid crystal display element according to the first embodiment of the present disclosure. [Figure 3] This is a plan view showing a first configuration example of a liquid crystal display element according to the first embodiment. [Figure 4] This is an explanatory diagram illustrating the overview of a brightness-modulated liquid crystal element. [Figure 5] This is an explanatory diagram illustrating the overview of a phase-modulated liquid crystal element. [Figure 6] This is a cross-sectional view showing a second configuration example of a liquid crystal display element according to a comparative example. [Figure 7] This is a cross-sectional view showing a second configuration example of a liquid crystal display element according to the first embodiment. [Figure 8] This is a plan view showing a modified example 1 of the liquid crystal display element according to the first embodiment. [Figure 9] This is a cross-sectional view showing a modified example 2 of the liquid crystal display element according to the first embodiment. [Figure 10] This is a cross-sectional view showing a first configuration example of a display device according to the first embodiment. [Figure 11] This is a cross-sectional view showing a second configuration example of the display device according to the first embodiment. [Figure 12] This is a cross-sectional view showing an example configuration of a liquid crystal display element and a display device according to a comparative example. [Figure 13] This is a cross-sectional view showing an example configuration of a liquid crystal display element and display device according to a second embodiment. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described in detail below with reference to the drawings. The description will be given in the following order. 1. First embodiment (liquid crystal element with luminance modulation type effective pixel area) 1.1 Configuration and operation of liquid crystal display elements (Figures 1 to 7) 1.2 Modified Example (Figs. 8 and 9) 1.3 Application Example to Display Device (Figs. 10 and 11) 1.4 Effects 2. Second Embodiment (Liquid Crystal Element with Phase Modulation Type Active Pixel Region) (Figs. 12 and 13) 3. Other Embodiments

[0011] <1. First Embodiment (Liquid Crystal Element with Luminance Modulation Type Active Pixel Region)> [1.1 Structure and Operation of Liquid Crystal Display Element] (Liquid Crystal Display Element According to Comparative Example) Fig. 1 shows an example of the cross-sectional structure of a liquid crystal display element 101 according to the first configuration example of the comparative example. [[ID=__]]

[0012] [[ID=__]] As the first configuration example of the comparative example, a configuration example of a reflective liquid crystal display element is shown. This liquid crystal display element 101 is configured as a luminance modulation type liquid crystal element as a whole. This liquid crystal display element 101 includes a counter substrate 10 as a first substrate and a pixel substrate 20 as a second substrate. The pixel substrate 20 is disposed opposite to the counter substrate 10 so as to sandwich a liquid crystal layer 30 containing a plurality of liquid crystal molecules 31 between it and the counter substrate 10. The peripheries of the counter substrate 10 and the pixel substrate 20 are joined to each other via a sealing material 13. [[ID=__]]

[0013] [[ID=__]] The counter substrate 10 is made of an optically transparent material such as glass or a transparent resin. A counter electrode portion 11 as a first electrode portion is formed over the entire surface of the active pixel region 130 in the counter substrate 10 and the peripheral region 120 of the active pixel region 130 in the counter substrate 10. The counter electrode portion 11 is a common electrode formed of a transparent conductive film such as an ITO (Indium Tin Oxide) film. Also, in the counter substrate 10, a single alignment film 12 is formed over the entire surface so as to cover the counter electrode portion 11 in the active pixel region 130 and the peripheral region 120. The alignment direction of the alignment film 12 is, for example, a direction inclined 45° with respect to the polarization direction of incident light. The alignment film 12 is composed of, for example, a vapor deposition film made of an inorganic material or an organic film obtained by rubbing an organic material such as polyimide.

[0014] The effective pixel area 130 is, for example, a rectangular area when the liquid crystal display element 101 is viewed from above. The peripheral area 120 is an area that surrounds the rectangular effective pixel area 130 when the liquid crystal display element 101 is viewed from above.

[0015] The pixel substrate 20 is made of, for example, a TFT (Thin Film Transistor) substrate. A pixel electrode portion 21A is formed in the effective pixel region 130 of the pixel substrate 20. The pixel electrode portion 21A includes, for example, a plurality of pixel electrodes arranged in a matrix. In addition, a peripheral drive electrode portion 21B is formed in the peripheral region 120 of the effective pixel region 130 of the pixel substrate 20. Furthermore, in the pixel substrate 20, a single alignment film 22 is formed so as to cover the entire surface of the pixel electrode portion 21A and the peripheral drive electrode portion 21B in both the effective pixel region 130 and the peripheral region 120. The orientation direction of the alignment film 22 is, for example, a direction tilted at 45° with respect to the polarization direction of the incident light. The alignment film 22 is made of, for example, a vapor-deposited film of an inorganic material, or an organic film obtained by rubbing an organic material such as polyimide.

[0016] The peripheral drive electrode section 21B includes one or more electrodes. The peripheral drive electrode section 21B can generate a transverse electric field by applying a periodically alternating rectangular drive voltage between adjacent electrodes in multiple electrodes, for example, thereby moving impurity ions to the peripheral region 120. In the case where a rectangular drive voltage is also applied to the pixel electrode section 21A, the frequency of the drive voltage applied to the peripheral drive electrode section 21B may be set higher than the frequency of the drive voltage applied to the pixel electrode section 21A. Alternatively, the magnitude (amplitude) of the drive voltage applied to the peripheral drive electrode section 21B may be set larger than the magnitude (amplitude) of the drive voltage applied to the pixel electrode section 21A.

[0017] In the liquid crystal display element 101, in the effective pixel region 130, incident light incident on the opposing substrate 10 is modulated by the liquid crystal layer 30 and reflected by the pixel electrode portion 21A, and emitted from the opposing substrate 10 side. In the liquid crystal display element 101, reflected light in a direction where the polarization direction (reflected polarization axis) is perpendicular to the polarization direction (incident polarization axis) of the incident light is emitted as emitted light L1 via the analyzer 41. The analyzer 41 is, for example, a polarizer having a predetermined transmission polarization axis. The transmission polarization axis of the analyzer 41 is configured to be in the same direction as the reflected polarization axis of the reflected light emitted from the liquid crystal display element 101.

[0018] In the liquid crystal display element 101, alignment films 12 and 22 with the same orientation direction are formed in the effective pixel area 130 and the peripheral area 120. Therefore, even in the peripheral area 120, incident light incident on the opposing substrate 10 is modulated by the liquid crystal layer 30 and reflected by the peripheral drive electrode section 21B, and emitted from the opposing substrate 10 side. In other words, in the liquid crystal display element 101, even in the peripheral area 120, reflected light in a direction where the polarization direction (reflection polarization axis) is perpendicular to the polarization direction (incident polarization axis) of the incident light is emitted as emitted light L2 via the analyzer 41. This emitted light L2 in the peripheral area 120 becomes unwanted light. In this case, it is conceivable to suppress unwanted light by providing a light-shielding mask 51 as a mechanical light-shielding part. However, by providing a light-shielding mask 51, vignetting of the light rays may occur in the emitted light L1 from the effective pixel area 130, potentially causing image quality degradation. Therefore, with the configuration of the liquid crystal display element 101, it is difficult to suppress vignetting of the light L1 emitted from the effective pixel area 130 while suppressing image quality degradation due to impurity ions by the peripheral drive electrode section 21B.

[0019] (Liquid crystal display element according to the first embodiment) Figure 2 shows an example of the cross-sectional configuration of the liquid crystal display element 1 according to the first configuration example of the first embodiment of the present disclosure. Figure 3 shows an example of the planar configuration of the liquid crystal display element 1 according to the first configuration example of the first embodiment. The following section describes the differences between the liquid crystal display element 101 and the comparative example shown in Figure 1.

[0020] As a first example of the configuration of the first embodiment, an example of the configuration of a reflective liquid crystal display element is shown. In this liquid crystal display element 1, a first alignment film (alignment film 12A, alignment film 22A) is formed in the effective pixel region 130 of the opposing substrate 10 and the pixel substrate 20, respectively. Alignment film 12A is formed on the opposing substrate 10 so as to cover the opposing electrode portion 11 in the effective pixel region 130. Alignment film 22A is formed on the pixel substrate 20 so as to cover the pixel electrode portion 21A in the effective pixel region 130. The alignment direction (first azimuthal angle) of alignment film 12A and alignment film 22A is, for example, a direction tilted at 45° with respect to the polarization direction of incident light. 12A and alignment film 22A For example, it is composed of a vapor-deposited film made of inorganic material, or an organic film made by rubbing an organic material such as polyimide.

[0021] Furthermore, in this liquid crystal display element 1, a second alignment layer (alignment layer 12B, alignment layer 22B) is formed in the peripheral region 120 of the opposing substrate 10 and the pixel substrate 20, respectively. Alignment layer 12B is formed on the opposing substrate 10 so as to cover the opposing electrode portion 11 in the peripheral region 120. Alignment layer 22B is formed on the pixel substrate 20 so as to cover the peripheral drive electrode portion 21B in the peripheral region 120. The alignment direction (second azimuth angle) of alignment layer 12B and alignment layer 22B is configured to be 45° different from the alignment direction (first azimuth angle) of alignment layer 12A and alignment layer 22A. The alignment direction (second azimuth angle) of alignment layer 12B and alignment layer 22B is, for example, parallel to the polarization direction of incident light. Alternatively, the alignment direction (second azimuth angle) of alignment layer 12B and alignment layer 22B may be configured to be perpendicular to the polarization direction of incident light. The alignment films 12B and 22B are composed of, for example, vapor-deposited films made of inorganic materials, or organic films made by rubbing organic materials such as polyimide.

[0022] This liquid crystal display element 1 is configured to operate as a luminance-modulated liquid crystal element in the effective pixel area 130 and as a phase-modulated liquid crystal element (SLM (Spatial Light Modulator)) in the peripheral area 120. Figure 4 shows an overview of the luminance-modulated liquid crystal element. Figure 5 shows an overview of the phase-modulated liquid crystal element. Figures 4 and 5 show examples of the configuration of a transmissive liquid crystal element for illustrative purposes.

[0023] In a luminance-modulated liquid crystal element, a polarizer 42, for example, made of a polarizing plate, is generally positioned in the direction of light incidence, and an analyzer 41, for example, also made of a polarizing plate, is positioned in the direction of light emission. The polarizer 42 has a predetermined transmission polarization axis and emits polarized light polarized in a predetermined polarization direction. In a luminance-modulated liquid crystal element, the orientation direction of the liquid crystal molecules 31 in the liquid crystal layer 30 (the long axis of the liquid crystal molecules 31) is, for example, as shown in Figure 4, tilted at 45° with respect to the transmission polarization axis of the polarizer 42 when viewed from the front. The inclination within the cross-section of the liquid crystal molecules 31 changes according to the voltage applied to the liquid crystal layer 30. As a result, the polarization state of the modulated light emitted from the luminance-modulated liquid crystal element changes according to the applied voltage. Finally, the amount of light emitted from the analyzer 41 changes according to the polarization state of the modulated light.

[0024] For example, when the liquid crystal layer 30 is untreated, the liquid crystal molecules 31 are oriented almost perpendicular to the substrate surface of the liquid crystal element. Linearly polarized light incident on the liquid crystal layer 30 passes through the liquid crystal layer 30 with little influence from the liquid crystal molecules 31. Under conditions where the polarizer 42 and analyzer 41 are arranged in crossed nicols, the final light emission state is black.

[0025] Furthermore, for example, when a predetermined voltage is applied to the liquid crystal layer 30, the liquid crystal molecules 31 become oriented almost parallel to the substrate surface of the liquid crystal element. In this case, linearly polarized light incident on the liquid crystal layer 30 becomes linearly polarized light rotated by 90° within the liquid crystal layer 30. Under conditions where the polarizer 42 and analyzer 41 are arranged in crossed nicols, the modulated light passes through the analyzer 41, and the final light emission state is displayed as white.

[0026] In phase-modulated liquid crystal elements, generally, a polarizer 42, for example, made of a polarizing plate, is positioned in the direction of light incidence, and an analyzer is positioned in the direction of light emission. 41 It is not arranged. In a phase-modulated liquid crystal element, the orientation direction of the liquid crystal molecules 31 in the liquid crystal layer 30 (the long axis of the liquid crystal molecules 31) is, for example, parallel to the transmitted polarization axis of the polarizer 42 when viewed from the front, as shown in Figure 5. The inclination of the liquid crystal molecules 31 within the cross-section changes according to the voltage applied to the liquid crystal layer 30. As a result, the phase state of the modulated light emitted from the phase-modulated liquid crystal element changes according to the applied voltage.

[0027] In phase-modulated liquid crystal elements, only the phase of light changes due to the tilt of the liquid crystal molecules 31, and the polarization state does not change, so the brightness remains unchanged.

[0028] For example, when the liquid crystal layer 30 is untreated, the liquid crystal molecules 31 are oriented almost perpendicular to the substrate surface of the liquid crystal element. The polarization direction of linearly polarized light incident on the liquid crystal layer 30 coincides with the director of the liquid crystal molecules 31, so the polarization direction does not change. If the refractive index of the liquid crystal layer 30 in this state is n1 and the thickness of the liquid crystal layer 30 is d, then the phase delay of the light emitted from the phase-modulated liquid crystal element is n1d.

[0029] Furthermore, for example, when a predetermined voltage is applied to the liquid crystal layer 30, the liquid crystal molecules 31 become oriented almost parallel to the substrate surface of the liquid crystal element. In this case, the polarization direction of linearly polarized light incident on the liquid crystal layer 30 coincides with the director of the liquid crystal molecules 31, so the polarization direction does not change. When the liquid crystal molecules 31 are parallel to the substrate surface of the liquid crystal element, the refractive index anisotropy of the liquid crystal molecules 31 is maximized. The refractive index of the liquid crystal layer 30 is obtained by subtracting the refractive index no of the ordinary light from the refractive index ne of the extraordinary light. If the refractive index of the liquid crystal layer 30 in this state is n2 and the thickness of the liquid crystal layer 30 is d, then the phase delay of the light emitted from the phase-modulated liquid crystal element is n2d.

[0030] Returning to Figures 2 and 3, we will explain the liquid crystal display element 1 again.

[0031] In the liquid crystal display element 1, as described above, a first alignment layer and a second alignment layer are formed in the effective pixel region 130 and the peripheral region 120, with their alignment directions differing by 45° from each other. As a result, the effective pixel region 130 operates as a luminance-modulated liquid crystal element, and the peripheral region 120 operates as a phase-modulated liquid crystal element. Therefore, in the peripheral region 120, even if the incident light incident on the opposing substrate 10 is modulated by the liquid crystal layer 30, the polarization direction does not change, only the phase changes. In the peripheral region 120, even if reflected light whose polarization direction (reflected polarization axis) is parallel to the polarization direction (incident polarization axis) of the incident light reaches the analyzer 41 as emitted light L2, it is blocked by the analyzer 41. In other words, it is possible to suppress unwanted light without providing a light-shielding mask 51 to suppress unwanted light, as in the liquid crystal display element 101 in the comparative example shown in Figure 1. As a result, the liquid crystal display element 1 can suppress vignetting of emitted light L1 from the effective pixel region 130 while suppressing image quality degradation due to impurity ions by the peripheral drive electrode section 21B.

[0032] Although the above explanation uses a reflective liquid crystal display element as an example, this technology can also be applied to transmissive liquid crystal display elements.

[0033] Figure 6 shows an example of the cross-sectional configuration of the liquid crystal display element 102 according to the second configuration example of the comparative example.

[0034] This section describes the differences between the liquid crystal display element 101 and the comparative example shown in Figure 1. Furthermore, this section explains the case where a polarizer 42, consisting of a polarizing plate, is positioned on the pixel substrate 20 side, and an analyzer 41 is positioned on the opposing substrate 10 side. The transmitted polarization axes of the polarizer 42 and the analyzer 41 are orthogonal to each other, and the polarizer 42 and the analyzer 41 are positioned in a cross-nicol configuration.

[0035] In the liquid crystal display element 102, in the effective pixel region 130, incident light incident on the pixel substrate 20 is modulated by the liquid crystal layer 30 and emitted from the opposite substrate 10 side. In the liquid crystal display element 102, transmitted light in a direction whose polarization direction is perpendicular to the polarization direction of the incident light (incident polarization axis) is emitted as emitted light L11 via the analyzer 41.

[0036] In the liquid crystal display element 102, alignment films 12 and 22 with the same orientation direction are formed in the effective pixel area 130 and the peripheral area 120. Therefore, even in the peripheral area 120, incident light incident on the pixel substrate 20 is modulated by the liquid crystal layer 30 and emitted from the opposing substrate 10 side. In other words, in the liquid crystal display element 102, even in the peripheral area 120, transmitted light in a direction perpendicular to the polarization direction of the incident light (incident polarization axis) is emitted as emitted light L12 via the analyzer 41. This emitted light L12 in the peripheral area 120 becomes unwanted light. In this case, it is conceivable to suppress unwanted light by providing a light-shielding mask 51 as a mechanical light-shielding part. However, by providing a light-shielding mask 51, vignetting of the light rays may occur in the emitted light L11 from the effective pixel area 130, potentially causing image quality degradation. Therefore, with the configuration of the liquid crystal display element 102, it is difficult to suppress vignetting of the light L11 emitted from the effective pixel area 130 while suppressing image quality degradation due to impurity ions by the peripheral drive electrode section 21B.

[0037] Figure 7 shows an example of the cross-sectional configuration of the liquid crystal display element 2 according to the second configuration example of the first embodiment. The following describes the differences between the liquid crystal display element 102 in the comparative example shown in Figure 6 and the liquid crystal display element 1 shown in Figure 2. Here, we will explain using the case where a polarizer 42, made of a polarizing plate, is placed on the pixel substrate 20 side, and an analyzer 41 is placed on the opposing substrate 10 side. The transmitted polarization axis of the polarizer 42 and the transmitted polarization axis of the analyzer 41 are orthogonal to each other, and the polarizer 42 and the analyzer 41 are arranged in a cross-nicol configuration.

[0038] In the liquid crystal display element 2, a first alignment layer (alignment layer 12A, alignment layer 22A) and a second alignment layer (alignment layer 12B, alignment layer 22B) are formed in the effective pixel region 130 and the peripheral region 120, with their alignment directions differing by 45° from each other. As a result, the element operates as a luminance-modulated liquid crystal element in the effective pixel region 130 and as a phase-modulated liquid crystal element in the peripheral region 120. Therefore, in the peripheral region 120, even if the incident light incident on the pixel substrate 20 is modulated by the liquid crystal layer 30, the polarization direction does not change, only the phase changes. In the peripheral region 120, even if transmitted light whose polarization direction is parallel to the polarization direction of the incident light (incident polarization axis) reaches the analyzer 41 as emitted light L12, it is blocked by the analyzer 41. In other words, it is possible to suppress unwanted light without providing a light-shielding mask 51 to suppress unwanted light, as in the liquid crystal display element 102 in the comparative example shown in Figure 6. As a result, the liquid crystal display element 2 can suppress image quality degradation due to impurity ions by the peripheral drive electrode section 21B, while also suppressing vignetting of the light L11 emitted from the effective pixel area 130.

[0039] [1.2 Variant] (Variation 1) Figure 8 shows one example of a modified configuration of the liquid crystal display element 1 according to the first embodiment.

[0040] In the configuration example shown in Figure 3, the liquid crystal molecules 31 in the peripheral region 120 are configured to be parallel to the horizontal direction when the liquid crystal display element 1 is viewed from above. However, as shown in Figure 8, the liquid crystal molecules 31 in the peripheral region 120 may be configured to be parallel to the vertical direction when viewed from above. In this case as well, the orientation direction (second azimuthal angle) of the second alignment layer (alignment layer 12B, alignment layer 22B) is configured to be 45° different from the orientation direction (first azimuthal angle) of the first alignment layer (alignment layer 12A, alignment layer 22A).

[0041] (Modification 2) Figure 9 shows an example configuration of a modified example 2 of the liquid crystal display element 1 according to the first embodiment.

[0042] In addition to the configuration of the liquid crystal display element 1 shown in Figure 2, the peripheral drive electrode section 21B may be configured to include multiple electrodes. In this case, by applying a periodically alternating rectangular drive voltage between adjacent electrodes in the multiple electrodes, a transverse electric field is generated, making it possible to move impurity ions to the peripheral region 120. In the case where a rectangular drive voltage is also applied to the pixel electrode section 21A, the frequency of the drive voltage applied to the peripheral drive electrode section 21B may be set higher than the frequency of the drive voltage applied to the pixel electrode section 21A. Furthermore, the magnitude (amplitude) of the drive voltage applied to the peripheral drive electrode section 21B may be set to be larger than the magnitude (amplitude) of the drive voltage applied to the pixel electrode section 21A.

[0043] [1.3 Examples of application to display devices] Figure 10 shows a first configuration example of a display device according to the first embodiment. Figure 10 shows a configuration example of a projection-type display device (projector) using a reflective liquid crystal display element as the display device. As the reflective liquid crystal display element, for example, the liquid crystal display element 1 shown in Figure 2 can be used.

[0044] The display device shown in Figure 10 comprises a light source 60, an illumination optical system 61, a PBS (polarizing beam splitter) 62, a liquid crystal display element 1, and a projection optical system 70.

[0045] The light source 60 is, for example, a laser light source. The illumination optical system 61 includes a fly-eye lens, a collimating lens, etc. The illumination optical system 61 emits light from the light source 60 as illumination light toward the PBS 62. The PBS 62 reflects, for example, S-polarized light and transmits P-polarized light. The PBS 62 acts as a polarizer for the illumination light from the illumination optical system 61. The PBS 62 emits S-polarized light toward the liquid crystal display element 1. The liquid crystal display element 1 modulates the S-polarized light and emits P-polarized light toward the PBS 62. The PBS 62 acts as an analyzer for the light emitted from the liquid crystal display element 1. Modulated light from the liquid crystal display element 1 is incident on the projection optical system 70 via the PBS 62. The projection optical system 70 is, for example, a projection lens. The projection optical system 70 projects the modulated light from the liquid crystal display element 1 as an image onto the screen 71.

[0046] Figure 11 shows a second configuration example of the display device according to the first embodiment.

[0047] Figure 11 shows an example configuration of a projection-type display device (projector) using a transmissive liquid crystal display element as the display device. As the transmissive liquid crystal display element, for example, the liquid crystal display element 2 shown in Figure 7 can be used.

[0048] The display device shown in Figure 11 comprises a light source 60, an illumination optical system 61, a polarizer 42, a liquid crystal display element 2, an analyzer 41, and a projection optical system 70. The transmitted polarization axis of the polarizer 42 and the transmitted polarization axis of the analyzer 41 are orthogonal to each other, and the polarizer 42 and the analyzer 41 are arranged in a cross-nicol configuration.

[0049] The light source 60 is, for example, a laser light source. The illumination optical system 61 includes a fly-eye lens, a collimating lens, etc. The illumination optical system 61 emits light from the light source 60 as illumination light towards the liquid crystal display element 2 via the analyzer 41. The liquid crystal display element 2 modulates the incident light and emits it towards the analyzer 41. The modulated light from the liquid crystal display element 2 is incident on the projection optical system 70 via the analyzer 41. The projection optical system 70 is, for example, a projection lens. The projection optical system 70 projects the modulated light from the liquid crystal display element 2 as an image onto the screen 71.

[0050] [1.4 Effects] As described above, according to the liquid crystal display element and display device according to the first embodiment, a peripheral drive electrode portion 21B is formed in the peripheral region 120 of the effective pixel region 130, and a second alignment layer (alignment layer 12B, alignment layer 22B) is formed in the peripheral region 120, having an azimuth angle that is 45° different from the first alignment layer (alignment layer 12A, alignment layer 22A) formed in the effective pixel region 130. This makes it possible to suppress image quality degradation and the generation of unwanted light.

[0051] The effects described herein are merely illustrative and not limiting, and other effects may also exist. The same applies to the effects of other embodiments described later.

[0052] <2. Second Embodiment (Liquid Crystal Element with Phase-Modulated Effective Pixel Area)> Next, a liquid crystal display element and a display device according to a second embodiment of the present disclosure will be described. In the following, parts that are substantially the same as the components of the liquid crystal display element and display device according to the first embodiment will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate.

[0053] Figure 12 shows an example configuration of a liquid crystal display element 102A and a display device according to a comparative example.

[0054] The display device shown in Figure 12 comprises a light source 80, an illumination optical system 81, a liquid crystal display element 102A, a light-shielding mask 82, and a projection optical system 90.

[0055] The comparative example liquid crystal display element 102A has an effective pixel area 130A and a peripheral area 120A, and the entire element, including the effective pixel area 130A and the peripheral area 120A, is configured as a phase-modulated liquid crystal element. The effective pixel area 130A is provided with a counter electrode portion 11 and a pixel electrode portion 21A, similar to the liquid crystal display element in the comparative example of the first embodiment. The peripheral area 120A is provided with a counter electrode portion 11 and a peripheral drive electrode portion 21B, similar to the liquid crystal display element in the comparative example of the first embodiment.

[0056] The light source 80 is, for example, a laser light source. The illumination optical system 81 includes a fly-eye lens, a collimating lens, etc. The illumination optical system 81 emits light from the light source 80 as illumination light toward the liquid crystal display element 102A. The liquid crystal display element 102A phase-modulates the incident light and emits it toward the projection optical system 90. The projection optical system 90 is, for example, a projection lens. The projection optical system 90 projects the modulated light from the liquid crystal display element 102A as an image onto the screen 71.

[0057] In this case, the liquid crystal display element 102A, similar to the liquid crystal display element in the comparative example of the first embodiment, has an alignment film formed in the effective pixel area 130A and the peripheral area 120A with the same orientation direction. Therefore, even in the peripheral area 120A, light is phase-modulated and emitted. This emitted light in the peripheral area 120A becomes unwanted light. In this case, it is conceivable to suppress unwanted light by providing a light-shielding mask 82 as a mechanical light-shielding part. However, by providing a light-shielding mask 82, vignetting of the light rays emitted from the effective pixel area 130A may occur, potentially causing image quality degradation. Therefore, in the configuration of the liquid crystal display element 102A, it is difficult to suppress vignetting of the light emitted from the effective pixel area 130A while suppressing image quality degradation due to impurity ions with the peripheral drive electrode section 21B.

[0058] Figure 13 shows an example configuration of a liquid crystal display element 2A and a display device according to the second embodiment. The following describes the differences between the liquid crystal display element 102A and the display device in the comparative example shown in Figure 12.

[0059] The display device shown in Figure 13 comprises a light source 80, an illumination optical system 81, a liquid crystal display element 2A, an analyzer 83, and a projection optical system 90.

[0060] In the liquid crystal display element 2A, a first alignment film and a second alignment film are formed in the effective pixel region 130A and the peripheral region 120A, respectively, with their alignment directions differing by 45° from each other. As a result, the liquid crystal display element operates as a phase-modulated liquid crystal element in the effective pixel region 130A and as a luminance-modulated liquid crystal element in the peripheral region 120A. In the liquid crystal display element 2A, the alignment direction (first azimuthal angle) of the first alignment film formed in the effective pixel region 130A is parallel (0°) to the polarization direction of the incident light. The alignment direction (second azimuthal angle) of the second alignment film formed in the peripheral region 120A is tilted at 45°. Therefore, in the liquid crystal display element 2A, the polarization direction of the incident light is rotated by 90° in the peripheral region 120A. Even if the light emitted from the peripheral region 120A reaches the analyzer 83, it is blocked by the analyzer 83. The transmitted polarization axis of the analyzer 83 is in the same direction as the light emitted from the effective pixel area 130A of the liquid crystal display element 2A, and the light emitted from the effective pixel area 130A passes through the analyzer 83. In other words, the liquid crystal display element 2A can suppress unwanted light without providing a light-shielding mask 82 to suppress unwanted light, as is the case with the liquid crystal display element 102A in the comparative example shown in Figure 12. As a result, the liquid crystal display element 2A can suppress vignetting of the light emitted L11 from the effective pixel area 130A while suppressing image quality degradation due to impurity ions with the peripheral drive electrode section 21B.

[0061] Other configurations, operations, and effects may be substantially the same as those of the liquid crystal display element and display device according to the first embodiment described above.

[0062] <3. Other Embodiments> The technology described herein is not limited to the embodiments described above and can be modified in various ways.

[0063] For example, this technology can also take the following configuration. According to this technology with the following configuration, peripheral drive electrodes are placed in the peripheral region of the effective pixel area. DepartmentIn addition to the formation of the first alignment layer in the effective pixel area, a second alignment layer is formed in the peripheral area, with an azimuth angle 45° different from that of the first alignment layer formed in the effective pixel area. This makes it possible to suppress image quality degradation and the generation of unwanted light.

[0064] (1) The first substrate and A second substrate is positioned opposite the first substrate so as to sandwich a liquid crystal layer containing multiple liquid crystal molecules between the first substrate and the second substrate, The effective pixel region in the first substrate, and the first electrode portion formed in the peripheral region of the effective pixel region in the first substrate, The pixel electrode portion formed in the effective pixel region of the second substrate, and the peripheral drive electrode formed in the peripheral region of the second substrate. Department A second electrode portion having, A first alignment film is formed in the effective pixel region of the first substrate and the second substrate, and its orientation direction is set to a first azimuthal angle, A second alignment film is formed in the peripheral region of each of the first and second substrates, and its orientation direction is set to a second azimuth angle that is 45° different from the first azimuth angle. Equipped with Liquid crystal display element. (2) The first azimuth angle is in a direction tilted at 45° with respect to the polarization direction of the incident light. The second azimuth angle is parallel or perpendicular to the polarization direction of the incident light. The liquid crystal display element described in (1) above. (3) The system is configured to operate as a luminance-modulated liquid crystal element in the effective pixel region and as a phase-modulated liquid crystal element in the peripheral region. The liquid crystal display element described in (2) above. (4) The first azimuth angle is parallel to the polarization direction of the incident light, The second azimuth angle is in a direction tilted 45° with respect to the polarization direction of the incident light. The liquid crystal display element described in (1) above. (5) The system is configured to operate as a phase-modulated liquid crystal element in the effective pixel region and as a luminance-modulated liquid crystal element in the peripheral region. The liquid crystal display element described in (4) above. (6) The peripheral drive electrode Department It includes multiple electrodes. A liquid crystal display element as described in any one of (1) through (5) above. (7) The peripheral drive electrode Department In the plurality of electrodes, a periodically alternating driving voltage is applied between adjacent electrodes. The liquid crystal display element described in (6) above. (8) LCD display buttons and A projection optical system that projects an image generated by the liquid crystal display element. Includes, The aforementioned liquid crystal display screen is The first substrate and A second substrate is positioned opposite the first substrate so as to sandwich a liquid crystal layer containing multiple liquid crystal molecules between the first substrate and the second substrate, The effective pixel region in the first substrate, and the first electrode portion formed in the peripheral region of the effective pixel region in the first substrate, The pixel electrode portion formed in the effective pixel region of the second substrate, and the peripheral drive electrode formed in the peripheral region of the second substrate. Department A second electrode portion having, A first alignment film is formed in the effective pixel region of the first substrate and the second substrate, and its orientation direction is set to a first azimuthal angle, A second alignment film is formed in the peripheral region of each of the first and second substrates, and its orientation direction is set to a second azimuth angle that is 45° different from the first azimuth angle. Equipped with Display device. (9) The further includes an analyzer positioned on the light emission side from the liquid crystal display element. The display device described in (8) above.

[0065] This application claims priority based on Japanese Patent Application No. 2021-205013, filed with the Japan Patent Office on 17 December 2021, and all contents of that application are incorporated herein by reference.

[0066] Those skilled in the art will understand that various modifications, combinations, subcombinations, and changes can be conceived depending on design requirements and other factors, and that these fall within the scope of the attached claims and their equivalents.

Claims

1. The first substrate and A second substrate is positioned opposite the first substrate so as to sandwich a liquid crystal layer containing a plurality of liquid crystal molecules between the first substrate and the second substrate, The first substrate comprises an effective pixel region and a first electrode portion formed in the peripheral region of the effective pixel region, A second electrode portion having a pixel electrode portion formed in the effective pixel region of the second substrate and a peripheral drive electrode portion formed in the peripheral region of the second substrate, A first alignment film is formed in the effective pixel region of the first substrate and the second substrate, and its orientation direction is set to a first azimuthal angle, A second alignment film is formed in the peripheral region of each of the first and second substrates, and its orientation direction is set to a second azimuth angle that is 45° different from the first azimuth angle. Equipped with, The first azimuth angle is parallel to the polarization direction of the incident light, The second azimuth angle is in a direction tilted 45° with respect to the polarization direction of the incident light. Liquid crystal display element.

2. The system is configured to operate as a phase-modulated liquid crystal element in the effective pixel region and as a luminance-modulated liquid crystal element in the peripheral region. The liquid crystal display element according to claim 1.

3. The peripheral drive electrode section includes a plurality of electrodes. The liquid crystal display element according to claim 1.

4. A periodically alternating drive voltage is applied between adjacent electrodes in the plurality of electrodes of the peripheral drive electrode section. The liquid crystal display element according to claim 3.

5. LCD display buttons and A projection optical system that projects an image generated by the liquid crystal display element. Includes, The aforementioned liquid crystal display screen is The first substrate and A second substrate is positioned opposite the first substrate so as to sandwich a liquid crystal layer containing a plurality of liquid crystal molecules between the first substrate and the second substrate, The first substrate comprises an effective pixel region and a first electrode portion formed in the peripheral region of the effective pixel region, A second electrode portion having a pixel electrode portion formed in the effective pixel region of the second substrate and a peripheral drive electrode portion formed in the peripheral region of the second substrate, A first alignment film is formed in the effective pixel region of the first substrate and the second substrate, and its orientation direction is set to a first azimuthal angle, A second alignment film is formed in the peripheral region of each of the first and second substrates, and its orientation direction is set to a second azimuth angle that is 45° different from the first azimuth angle. Equipped with, The first azimuth angle is parallel to the polarization direction of the incident light, The second azimuth angle is in a direction tilted 45° with respect to the polarization direction of the incident light. Display device.

6. The further includes an analyzer positioned on the light emission side from the liquid crystal display element. The display device according to claim 5.

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