Liquid crystal device and display device

Abstract

According to one embodiment, a liquid crystal device comprises: a first transparent substrate; a plurality of first light-shielding bodies each formed in a strip shape and arranged at a first pitch; a transparent first organic insulating film covering the plurality of first light-shielding bodies; a plurality of second light-shielding bodies each overlapping with the first light-shielding bodies and formed in a strip shape parallel to the first light-shielding bodies; a transparent second organic insulating film covering the plurality of second light-shielding bodies; a plurality of third light-shielding bodies each overlapping with the second light-shielding bodies and formed in a strip shape parallel to the second light-shielding bodies; a transparent third organic insulating film covering the plurality of third light-shielding bodies; an outer coating layer arranged above the third organic insulating film; a plurality of first electrodes arranged on the outer coating layer at a second pitch smaller than the first pitch; a second transparent substrate; a second electrode opposite to the plurality of first electrodes; and a liquid crystal layer.

Description

[0001] Cross-references between related applications

[0002] This application claims priority based on Japanese Patent Application No. 2021-146250, filed on September 8, 2021, and incorporates by reference all of the contents described in that Japanese patent application. Technical Field

[0003] Embodiments of the present invention relate to a liquid crystal device and a display apparatus. Background Art

[0004] In recent years, various optical elements for viewing angle control bonded to the display surface of a liquid crystal panel have been proposed. For example, these optical elements include a louver layer that limits the angle of light transmission. Louver layers are formed by alternating light-transmitting layers and light-shielding layers. The interface between the light-transmitting and light-shielding layers is tilted at a predetermined angle relative to the thickness of the louver layer.

[0005] When such an external optical element is used, the thickness of the entire device increases. Summary of the Invention

[0006] An object of the embodiment is to provide a liquid crystal device for viewing angle control that can achieve thickness reduction and a display device including the liquid crystal device.

[0007] According to one embodiment, a liquid crystal device comprises:

[0008] A first transparent substrate; a plurality of first light-shielding bodies, each formed in a strip shape and arranged at a first pitch on the inner surface of the first transparent substrate; a transparent first organic insulating film covering the plurality of first light-shielding bodies; a plurality of second light-shielding bodies, each overlapping the first light-shielding bodies, formed in a strip shape parallel to the first light-shielding bodies; a transparent second organic insulating film covering the plurality of second light-shielding bodies; a plurality of third light-shielding bodies, each overlapping the second light-shielding bodies, formed in a strip shape parallel to the second light-shielding bodies; a transparent third organic insulating film covering the plurality of third light-shielding bodies; an outer coating layer arranged above the third organic insulating film; a plurality of first electrodes, each formed in a strip shape, arranged on the outer coating layer at a second pitch smaller than the first pitch; a first orientation film covering the plurality of first electrodes; a second transparent substrate; a second electrode, arranged on the inner surface of the second transparent substrate, opposite to the plurality of first electrodes; a second orientation film covering the second electrode; and a liquid crystal layer arranged between the first orientation film and the second orientation film.

[0009] According to one embodiment, a display device includes:

[0010] An illumination device; a display panel having a plurality of pixels arranged in a matrix; and a liquid crystal device disposed between the illumination device and the display panel, the liquid crystal device comprising: a first transparent substrate; a louver portion located on the first transparent substrate; an outer coating layer covering the louver portion; a liquid crystal lens portion located on the outer coating layer; and a second transparent substrate located on the liquid crystal lens portion, the louver portion being located between the illumination device and the liquid crystal lens portion.

[0011] According to the embodiment, a liquid crystal device for viewing angle control that can achieve thickness reduction and a display device including the liquid crystal device can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is an exploded perspective view showing the display device DSP according to the embodiment.

[0013] Figure 2 Yes Figure 1 FIG. 1 is a diagram showing an example of an equivalent circuit of the display panel PNL shown in FIG.

[0014] Figure 3 Yes Figure 1 FIG. 2 is a cross-sectional view showing an example of the structure of the display panel PNL.

[0015] Figure 4 Yes Figure 1 FIG. 2 is a cross-sectional view showing an example of the structure of the liquid crystal device 100 shown in FIG.

[0016] Figure 5 Yes Figure 4 1 is a cross-sectional view of a structural example of the liquid crystal lens unit 4 shown.

[0017] Figure 6 1 is a diagram schematically showing the liquid crystal device 100 in an off state (OFF) in which no electric field is formed in the liquid crystal layer LC1.

[0018] Figure 7 1 is a diagram schematically showing a liquid crystal device 100 in an on state (ON) in which an electric field is formed in the liquid crystal layer LC1.

[0019] Figure 8 It is a plan view showing a portion of the first electrode E1 and the light shielding layer B1.

[0020] Figure 9 It is a plan view showing a portion of the light shielding layer 21 and the light shielding layer B1 of the display panel PNL.

[0021] Figure 10 It is a plan view showing a portion of the first electrode E1 and other light shielding layers B1.

[0022] Figure 11It is a cross-sectional view showing another example of each light-shielding body constituting the louver portion 3 .

[0023] Figure 12 It is a cross-sectional view showing another example of each light-shielding body constituting the louver portion 3 .

[0024] Figure 13 It is a cross-sectional view showing another example of each light-shielding body constituting the louver portion 3 .

[0025] Figure 14 It is a diagram for explaining the opening ratio of the louver portion 3 .

[0026] Figure 15 It is a diagram for explaining the thickness c of the louver portion 3 . DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0028] Furthermore, the disclosure is merely an example, and appropriate modifications that would be readily apparent to those skilled in the art while maintaining the spirit of the invention are naturally within the scope of the present invention. Furthermore, to clarify the description, the drawings may sometimes schematically illustrate the width, thickness, shape, etc. of various components, as compared to actual embodiments. However, these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and the drawings, structural elements that perform the same or similar functions as those described above are denoted by the same reference numerals as those in the drawings that have already appeared, and duplicate detailed descriptions may be omitted as appropriate.

[0029] In the drawings, mutually orthogonal X-axis, Y-axis, and Z-axis are shown as needed to facilitate understanding. The direction along the X-axis is referred to as the X-direction or the first direction, the direction along the Y-axis is referred to as the Y-direction or the second direction, and the direction along the Z-axis is referred to as the Z-direction or the third direction. The plane defined by the X-axis and the Y-axis is referred to as the XY plane, and viewing the XY plane is referred to as a top view.

[0030] Figure 1 It is an exploded perspective view showing the display device DSP according to this embodiment.

[0031] The display device DSP includes an illumination device IL, a liquid crystal device 100 , a display panel PNL, an optical sheet OS, and polarizers PL1 and PL2 .

[0032] The illumination device IL is configured to emit illumination light toward the display panel PNL. The illumination light is, for example, unpolarized light, but may also be linearly polarized light.

[0033] The optical sheet OS is arranged between the illumination device IL and the liquid crystal device 100 in the third direction Z. The optical sheet OS is, for example, a reflective polarizing plate, and is configured to reflect s-polarized light in the illumination light and transmit p-polarized light.

[0034] The liquid crystal device 100 is disposed between the optical sheet OS and the polarizer PL1 in the third direction Z. The liquid crystal device 100 holds a liquid crystal layer between the first substrate S1 and the second substrate S2. The liquid crystal device 100 has an active area AA for controlling the emission direction of incident light (illumination light).

[0035] The display panel PNL is disposed between the polarizer PL1 and the polarizer PL2 in the third direction Z. The display panel PNL is, for example, a liquid crystal panel with a liquid crystal layer held between a pair of substrates SUB1 and SUB2. However, the illumination device IL may also illuminate another display panel PNL. The display panel PNL has a display area DA for displaying images. The display area DA overlaps with the active area AA in the third direction Z.

[0036] Note that the display panel PNL and the liquid crystal device 100 will be described in detail later.

[0037] Figure 2 Yes Figure 1 FIG. 1 is a diagram showing an example of an equivalent circuit of the display panel PNL shown in FIG.

[0038] The display panel PNL includes a plurality of pixels PX, a plurality of scanning lines G, and a plurality of signal lines S in the display area DA. The plurality of scanning lines G and the plurality of signal lines S intersect with each other. In one example, the plurality of scanning lines G are arranged in a plurality of pixels PX. Figure 1 The plurality of signal lines S extend in a first direction X as shown, and a plurality of signal lines S extend in a second direction Y.

[0039] The display panel PNL includes a first driver DR1 and a second driver DR2 outside the display area DA. Multiple scan lines G are electrically connected to the first driver DR1. Multiple signal lines S are electrically connected to the second driver DR2. The first driver DR1 and the second driver DR2 are controlled by a controller.

[0040] The pixel PX shown here is called a sub-pixel, a color pixel, etc., and corresponds to, for example, a red pixel that displays red, a green pixel that displays green, a blue pixel that displays blue, or a white pixel that displays white. Such a pixel PX is divided by, for example, two adjacent scanning lines G and two adjacent signal lines S.

[0041] Each pixel PX includes a switching element SW, a pixel electrode PE, and a common electrode CE opposing the pixel electrode PE. The switching element SW is electrically connected to a scanning line G and a signal line S. The pixel electrode PE is electrically connected to the switching element SW. In other words, the pixel electrode PE is electrically connected to the signal line S via the switching element SW. The common electrode CE is formed across multiple pixels PX. A common potential is applied to the common electrode CE.

[0042] The first driver DR1 supplies a scan signal to each scan line G. The second driver DR2 supplies an image signal to each signal line S. In the switching element SW electrically connected to the scan line G supplied with the scan signal, conduction is established between the signal line S and the pixel electrode PE, and a voltage corresponding to the image signal supplied to the signal line S is applied to the pixel electrode PE. The liquid crystal layer LC is driven by the electric field generated between the pixel electrode PE and the common electrode CE.

[0043] Figure 3 Yes Figure 1 FIG. 2 is a cross-sectional view showing an example of the structure of the display panel PNL.

[0044] The display panel PNL includes a substrate SUB1, a substrate SUB2, and a liquid crystal layer LC. While the display panel PNL is described here for a display mode utilizing a transverse electric field along the substrate principal surfaces, the structure of the display panel PNL is not limited thereto. The display panel PNL may also be configured to support any of the following display modes: a longitudinal electric field along the normal to the substrate principal surfaces; a tilted electric field tilted in a direction oblique to the substrate principal surfaces; or a display mode utilizing a suitable combination of the transverse electric field, longitudinal electric field, and tilted electric field. The substrate principal surface here refers to a surface parallel to the XY plane.

[0045] The substrate SUB1 includes a switching element SW, a pixel electrode PE, and a common electrode CE, as well as a transparent substrate 10, insulating layers 11 and 12, and an alignment film 13. Figure 1 The transparent substrate 10 includes a scanning line G, a signal line S, a first driver DR1, a second driver DR2, etc. The transparent substrate 10 has an inner surface 10A facing the liquid crystal layer LC and an outer surface 10B opposite to the inner surface 10A. A polarizing plate PL1 is bonded to the outer surface 10B.

[0046] The switching element SW is arranged on the inner surface 10A and is covered by the insulating layer 11. Figure 3 In the example shown, for ease of explanation, the switching element SW is simplified and the scanning lines G and signal lines S are omitted. In practice, the insulating layer 11 includes a plurality of insulating layers, and the switching element SW includes semiconductor layers and various electrodes formed between these insulating layers.

[0047] A common electrode CE is arranged across multiple pixels PX on the insulating layer 11 and is covered by the insulating layer 12. A pixel electrode PE for each pixel PX is arranged on the insulating layer 12, facing the common electrode CE via the insulating layer 12. Furthermore, the pixel electrode PE is electrically connected to the switching element SW via an opening OP penetrating the common electrode CE and a contact hole CH formed in the insulating layers 11 and 12. An alignment film 13 covers the pixel electrode PE and the insulating layer 12 and is in contact with the liquid crystal layer LC.

[0048] The substrate SUB2 includes a transparent substrate 20, a light-shielding layer 21, a color filter layer 22, an overcoat layer 23, and an alignment film 24. The transparent substrate 20 has an inner surface 20A facing the liquid crystal layer LC and an outer surface 20B opposite the inner surface 20A. A polarizing plate PL2 is bonded to the outer surface 20B.

[0049] The light-shielding layer 21 is disposed on the inner surface 20A, at the boundaries between adjacent pixels PX. Although described later, the light-shielding layer 21 is formed in a grid pattern that overlaps with the scanning lines G and the signal lines S, thereby dividing the pixels PX. The color filter layer 22 includes a red filter 22R, a green filter 22G, and a blue filter 22B. An overcoat layer 23 covers the color filter layer 22. An alignment film 24 covers the overcoat layer 23 and is in contact with the liquid crystal layer LC.

[0050] The transparent substrates 10 and 20 are insulating substrates such as glass substrates or resin substrates. The pixel electrodes PE and the common electrodes CE are transparent electrodes formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0051] Figure 4 Yes Figure 1 1 is a cross-sectional view of an example of the structure of the liquid crystal device 100. Here, a cross-sectional structure of a part of the active area AA is shown.

[0052] The liquid crystal device 100 includes a first substrate S1 , a second substrate S2 , and a liquid crystal layer LC1 .

[0053] The liquid crystal device 100 is built between a pair of transparent substrates 1 and 2 and includes: a louver section 3 for limiting the emission direction of incident light (illumination light) and collimating the incident light; and a liquid crystal lens section 4 for adjusting the divergence of the collimated incident light. The louver section 3 is located between the lighting device IL represented by the dotted line and the liquid crystal lens section 4. In the example shown here, the louver section 3 is built into the first substrate S1. The liquid crystal device 100 is configured to control the emission direction of the incident light (illumination light) in the effective area AA through the combination of these louver sections 3 and the liquid crystal lens section 4. The structure of each part is described below.

[0054] The first substrate S1 includes a first transparent substrate 1, a plurality of light shielding layers B1 to B5, a plurality of organic insulating films I1 to I4, an overcoat layer OC, a plurality of first electrodes E1, and a first alignment film AL1. The louver portion 3 is composed of the plurality of light shielding layers B1 to B5. Figure 4 In the example shown, the louver portion 3 is composed of five light-shielding layers B1 to B5 , but may be composed of two or more light-shielding layers arranged in the third direction Z.

[0055] The first transparent substrate 1 has an inner surface 1A facing the liquid crystal layer LC1 and an outer surface 1B opposite to the inner surface 1A. Figure 1 The optical sheets OS are shown facing each other.

[0056] The light-shielding layer B1 includes a plurality of light-shielding bodies B11 and B12 disposed on the inner surface 1A of the first transparent substrate 1. The plurality of light-shielding bodies B11 and B12 are arranged at a first pitch P1 in a first direction X. As described later, each of the light-shielding bodies B11 and B12 is formed in a strip shape extending in a direction intersecting the first direction X and is parallel to each other.

[0057] The organic insulating film I1 covers the light-shielding bodies B11 and B12 and also covers the first transparent substrate 1 .

[0058] The light-shielding layer B2 includes a plurality of light-shielding bodies B21 and B22 disposed on the organic insulating film I1. The plurality of light-shielding bodies B21 and B22 are in contact with the organic insulating film I1 and are arranged at a first pitch P1 in the first direction X. These light-shielding bodies B21 and B22 overlap with the light-shielding bodies B11 and B12, respectively, and are formed into strips parallel to the light-shielding bodies B11 and B12. That is, the light-shielding body B21 is located directly above the light-shielding body B11, across the organic insulating film I1, and the light-shielding body B22 is located directly above the light-shielding body B12, across the organic insulating film I1.

[0059] The organic insulating film I2 covers the light-shielding bodies B21 and B22 and also covers the organic insulating film I1 .

[0060] The light-shielding layer B3 includes a plurality of light-shielding bodies B31 and B32 disposed on the organic insulating film I2. The plurality of light-shielding bodies B31 and B32 are in contact with the organic insulating film I2 and are arranged at a first pitch P1 in the first direction X. These light-shielding bodies B31 and B32 overlap with the light-shielding bodies B21 and B22, respectively, and are formed into strips parallel to the light-shielding bodies B21 and B22, respectively. That is, the light-shielding body B31 is located directly above the light-shielding body B21 across the organic insulating film I2, and the light-shielding body B32 is located directly above the light-shielding body B22 across the organic insulating film I2.

[0061] The organic insulating film I3 covers the light-shielding bodies B31 and B32 and also covers the organic insulating film I2.

[0062] The light-shielding layer B4 includes a plurality of light-shielding bodies B41 and B42 disposed on the organic insulating film I3. The plurality of light-shielding bodies B41 and B42 are in contact with the organic insulating film I3 and are arranged at a first pitch P1 in the first direction X. These light-shielding bodies B41 and B42 overlap with the light-shielding bodies B31 and B32, respectively, and are formed into strips parallel to the light-shielding bodies B31 and B32, respectively. That is, the light-shielding body B41 is located directly above the light-shielding body B31 across the organic insulating film I3, and the light-shielding body B42 is located directly above the light-shielding body B32 across the organic insulating film I3.

[0063] The organic insulating film I4 covers the light-shielding bodies B41 and B42 and also covers the organic insulating film I3.

[0064] The light-shielding layer B5 includes a plurality of light-shielding bodies B51 and B52 disposed on the organic insulating film I4. The plurality of light-shielding bodies B51 and B52 are in contact with the organic insulating film I4 and are arranged at a first pitch P1 in the first direction X. These light-shielding bodies B51 and B52 overlap with the light-shielding bodies B41 and B42, respectively, and are formed into strips parallel to the light-shielding bodies B41 and B42, respectively. That is, the light-shielding body B51 is located directly above the light-shielding body B41 across the organic insulating film I4, and the light-shielding body B52 is located directly above the light-shielding body B42 across the organic insulating film I4.

[0065] The overcoat layer OC covers the light-shielding bodies B51 and B52 and the organic insulating film I4. That is, the overcoat layer OC covers the louver portion 3.

[0066] A plurality of first electrodes E1 are disposed on the overcoat layer OC. The plurality of first electrodes E1 are arranged at a second pitch P2 in the first direction X. The second pitch P2 is smaller than the first pitch P1. As described later, the plurality of first electrodes E1 are each formed into a strip extending in a direction intersecting the first direction X and are parallel to each other.

[0067] The first alignment film AL1 covers the plurality of first electrodes and the overcoat layer OC, and is in contact with the liquid crystal layer LC1.

[0068] In such a first substrate S1, for example, the light-shielding bodies B11 and B12 are equivalent to the first light-shielding body, the light-shielding bodies B21 and B22 are equivalent to the second light-shielding body, the light-shielding bodies B31 and B32 are equivalent to the third light-shielding body, the organic insulating film I1 is equivalent to the first organic insulating film, the organic insulating film I2 is equivalent to the second organic insulating film, and the organic insulating film I3 is equivalent to the third organic insulating film.

[0069] The second substrate S2 includes a second transparent substrate 2 , a second electrode E2 , and a second alignment film AL2 .

[0070] The second transparent substrate 2 has an inner surface 2A facing the liquid crystal layer LC1 and an outer surface 2B opposite to the inner surface 2A. Figure 1 The polarizing plates PL1 shown are opposed to each other.

[0071] The second electrode E2 is disposed on the inner surface 2A of the second transparent substrate 2. The second alignment film AL2 covers the second electrode E2 and is in contact with the liquid crystal layer LC1.

[0072] The spacer SP is formed in a columnar shape, for example, and is disposed between the first substrate S1 and the second substrate S2 to maintain a gap of, for example, 10 μm or more.

[0073] The liquid crystal layer LC1 is disposed between the first alignment film AL1 and the second alignment film AL2 , and a thickness TLC of the liquid crystal layer LC1 along the third direction Z is greater than or equal to 10 μm.

[0074] The liquid crystal lens unit 4 is composed of a plurality of first electrodes E1 , a liquid crystal layer LC1 , and second electrodes E2 .

[0075] The first transparent substrate 1 and the second transparent substrate 2 are insulating substrates such as glass substrates or resin substrates.

[0076] The light-blocking bodies B11 and B12 , the light-blocking bodies B21 and B22 , the light-blocking bodies B31 and B32 , the light-blocking bodies B41 and B42 , and the light-blocking bodies B51 and B52 are formed of, for example, a resin material containing a black pigment, but may also be formed of a metal material.

[0077] The organic insulating film I1 , the organic insulating film I2 , the organic insulating film I3 , the organic insulating film I4 , and the overcoat layer OC are formed of a transparent resin material such as acrylic resin.

[0078] The first electrode E1 and the second electrode E2 are transparent electrodes formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The first alignment film AL1 and the second alignment film AL2 are horizontal alignment films having an alignment regulating force substantially parallel to the XY plane.

[0079] Here, a case where the light-blocking bodies B11 , B21 , B31 , B41 , and B51 are each formed of a resin material will be described.

[0080] Each of the light-blocking bodies B11 , B21 , B31 , B41 , and B51 has a substantially rectangular cross-section.

[0081] The light shields B11 , B21 , B31 , B41 , and B51 have the same width a along the first direction X, for example, 5.5 μm. The interval b between the light shields arranged in the first direction X is larger than the width a, for example, 14.5 μm. The first pitch P1 is, for example, 20 μm.

[0082] The thicknesses T11 , T12 , T13 , T14 , and T15 of the light-blocking bodies B11 , B21 , B31 , B41 , and B51 along the third direction Z are equal to each other, and are preferably 1 μm or more, for example, 2 μm.

[0083] The thicker the light shielding members are, the fewer light shielding layers can be used to form the louver 3. Conversely, when the light shielding members are thin, a larger number of light shielding layers are required to form the louver 3 in order to collimate the transmitted light.

[0084] The thicknesses T1 , T2 , T3 , and T4 of the organic insulating films I1 , I2 , I3 , and I4 along the third direction Z are the same, for example, 8.5 μm.

[0085] The overcoat layer OC is thinner than the organic insulating film I1. That is, the thickness T5 of the overcoat layer OC along the third direction Z is smaller than the thickness T1, and is, for example, 2.5 μm.

[0086] The liquid crystal layer LC1 is thicker than the organic insulating film I1. That is, the thickness TLC of the liquid crystal layer LC1 is greater than the thickness T1, and is, for example, 10 μm. The overcoat layer OC is thinner than the liquid crystal layer LC1.

[0087] Figure 5 Yes Figure 4 A cross-sectional view of a structural example of the liquid crystal lens unit 4 is shown. Figure 5 In the figure, the louver portion 3 in the first substrate S1 is simplified, and the spacers are omitted. The liquid crystal layer LC1 is sealed by a sealant SE.

[0088] The first electrode E1 includes a plurality of first strip electrodes E11 and a plurality of second strip electrodes E12. The first strip electrodes E11 and the second strip electrodes E12 are alternately arranged in the first direction X at a second pitch P2.

[0089] The plurality of first strip electrodes E11 are electrically connected to one another and are applied with a first voltage via a power supply line FL1. The plurality of second strip electrodes E12 are electrically connected to one another and are applied with a second voltage via a power supply line FL2. The first voltage is different from the second voltage. This creates a potential difference between adjacent first strip electrodes E11 and second strip electrodes E12, thereby forming an electric field in the liquid crystal layer LC1.

[0090] The power supply terminal PT1 electrically connected to the power supply line FL3 is drawn out to the outside of the seal member SE. The power supply terminal PT1 is exposed from the first alignment film AL1.

[0091] The power supply terminal PT2 electrically connected to the second electrode E2 is led out to the outside of the seal SE. The power supply terminal PT2 is located directly above the power supply terminal PT1 and is exposed from the second alignment film AL2.

[0092] The conductive member CD is disposed between the power supply terminal PT1 and the power supply terminal PT2 to electrically connect the two.

[0093] Next, refer to Figure 6 and Figure 7 , the optical effect of the liquid crystal device 100 is described. Figure 6 and Figure 7 In the figure, only the structures necessary for the description are shown.

[0094] Figure 6 1 is a diagram schematically showing the liquid crystal device 100 in an off state (OFF) in which no electric field is formed in the liquid crystal layer LC1.

[0095] Among the illumination light emitted from the illumination device IL, p-polarized light POL1 that has passed through the optical sheet OS is incident on the first substrate S1 of the liquid crystal device 100 . The incident p-polarized light POL1 is collimated by the louver 3 of the first substrate S1 and then is incident on the liquid crystal lens 4 .

[0096] In the liquid crystal layer LC1 in the off state, the liquid crystal molecules LM1 are initially aligned. In this off state, the liquid crystal layer LC1 has a substantially uniform refractive index distribution. Therefore, p-polarized light POL1 incident on the liquid crystal lens unit 4 is barely refracted (or diverged) and passes through the liquid crystal layer LC1.

[0097] Therefore, when the liquid crystal lens portion 4 of the liquid crystal device 100 is off, illumination light with a relatively small divergence can be formed, and image display in a narrow viewing angle mode can be achieved using light that has passed through the display panel PNL.

[0098] Figure 7 1 is a diagram schematically showing the liquid crystal device 100 in an on state (ON) in which an electric field is formed in the liquid crystal layer LC1.

[0099] For example, if the liquid crystal layer LC1 has positive dielectric anisotropy, in the on state, when an electric field is applied to the liquid crystal layer LC1, the liquid crystal molecules LM1 align with their long axes along the electric field. For example, an electric field corresponding to the potential difference between adjacent first electrodes E1 and the potential difference between the first electrode E1 and the second electrode E2 is applied to the liquid crystal layer LC1. This electric field acts on the liquid crystal layer LC1, creating regions in the liquid crystal layer LC1 where the liquid crystal molecules LM1 stand approximately perpendicular to the substrates, regions where the liquid crystal molecules LM1 maintain their initial alignment, and regions where the liquid crystal molecules LM1 stand obliquely relative to the substrates.

[0100] Liquid crystal molecules LM1 have a refractive index anisotropy Δn. Therefore, the liquid crystal layer LC1 in the on state has a refractive index distribution or retardation distribution corresponding to the alignment of the liquid crystal molecules LM1. Retardation here is the value represented by Δn·d, when the thickness of the liquid crystal layer LC1 (or the gap between the first substrate S1 and the second substrate S2) is d.

[0101] In this on state, the collimated p-polarized light POL1 is diverged by the refractive index distribution of the liquid crystal layer LC1 when passing through the liquid crystal layer LC1. The degree of divergence of the transmitted light can be controlled by applying a voltage to the liquid crystal layer LC1.

[0102] Therefore, when the liquid crystal lens portion 4 of the liquid crystal device 100 is turned on, illumination light with a relatively large divergence can be formed, and image display in a wide viewing angle mode can be realized using the light that has passed through the display panel PNL.

[0103] In this manner, according to the liquid crystal device 100 including the louver portion 3 and the liquid crystal lens portion 4 , the emission direction of the illumination light emitted from the illumination device IL can be controlled.

[0104] Furthermore, according to the liquid crystal device 100 , the overall thickness of the device can be reduced compared to a case where an optical element including a liquid crystal lens portion between a pair of substrates is required in addition to a liquid crystal element including louvers on the substrates.

[0105] Figure 8 1 is a plan view showing a portion of the first electrode E1 and the light shielding layer B1. Note that, here, only the light shielding layer B1 is shown among the plurality of light shielding layers constituting the louver portion, but the light shielding layers B2 to B5 overlap each other directly above the light shielding layer B1.

[0106] As described above, the first electrode E1 includes the first strip electrodes E11 and the second strip electrodes E12 alternately arranged in the first direction X. The first strip electrodes E11 and the second strip electrodes E12 extend along the second direction Y, respectively.

[0107] The light-shielding layer B1 includes light-shielding bodies B11 to B15 arranged sequentially in the first direction X. The light-shielding bodies B11 to B15 are parallel to one another and extend in a direction different from the second direction Y. That is, when viewed from above, the light-shielding bodies B11 to B15 intersect the first electrode E1. In other words, the light-shielding bodies B11 to B15 extend in a direction different from the direction in which the first strip electrode E11 and the second strip electrode E12 extend.

[0108] For example, focusing on the light-blocking body B11, the reference orientation indicated by the dotted line in the figure is parallel to the second direction Y, and the light-blocking body B11 extends in a direction rotated clockwise by an angle θ from the reference orientation. The angle θ is an acute angle, for example, 4°.

[0109] When forming the liquid crystal lens unit 4, the smaller the second pitch P2, the lower the voltage applied to the liquid crystal layer LC1 and the smaller the thickness TLC of the liquid crystal layer LC1. Therefore, the second pitch P2 is preferably set to the minimum pitch that allows processing of the first electrode E1.

[0110] The first pitch P1 is set based on the required louver performance, aperture ratio, workability of the light-shielding body, etc. An example of setting the first pitch P1 will be described later.

[0111] Figure 9 2 is a plan view showing a portion of the light shielding layer 21 and the light shielding layer B1 of the display panel PNL. In addition, here, only the light shielding layer B1 among the plurality of light shielding layers constituting the louver portion is shown with a dotted line.

[0112] The light shielding layer 21 has a first portion 21X extending in the first direction X and a second portion 21Y extending in the second direction Y. For example, the first portion 21X overlaps with the scanning line G, and the second portion 21Y overlaps with the signal line S.

[0113] The quadrilateral opening AP formed in the light shielding layer 21 is Figure 3 The pixels PX or the pixel electrodes PE shown overlap. In one example, the opening AP is formed in a rectangular shape extending along the second direction Y, but is not limited to this shape.

[0114] The plurality of openings AP are arranged in a matrix along the first direction X and the second direction Y. For example, the plurality of openings AP are arranged along the first direction X at a pixel pitch P11.

[0115] The light shielding members B11 to B15 of the light shielding layer B1 intersect the first portion 21X and the second portion 21Y of the light shielding layer 21. The first pitch P1 of the light shielding members B11 to B15 is smaller than the pixel pitch P11. In one example, the pixel pitch P11 is 20 μm to 100 μm.

[0116] In this way, in the display device DSP, when the liquid crystal device 100 overlaps with the display panel PNL, the light shielding layer B1 and the light shielding layer 21 intersect with each other, and the pixel pitch P11 is different from the first pitch P1, thereby suppressing unwanted moiré fringes and suppressing the reduction of display quality.

[0117] Figure 10 1 is a plan view showing a portion of the first electrode E1 and other light shielding layers B1. Note that, here, only the light shielding layer B1 is shown among the plurality of light shielding layers constituting the louver portion.

[0118] Figure 10 The light shielding layer B1 shown is Figure 8 Compared with the light shielding layer B1 shown in FIG. 1 , the light shielding body is different in that it is formed in a sawtooth shape.

[0119] The light-shielding bodies B11 to B15 are parallel to each other and extend in a direction different from the second direction Y. In a plan view, the light-shielding bodies B11 to B15 intersect with the first electrode E1 .

[0120] Focusing on the light-blocking body B11, it comprises multiple first portions BA and multiple second portions BB. The first portions BA and second portions BB extend in different directions and are arranged alternately along the second direction Y. The reference orientation, indicated by the dashed line in the figure, is parallel to the second direction Y. The first portions BA extend in a direction rotated clockwise by an angle θA from the reference orientation, while the second portions BB extend in a direction rotated counterclockwise by an angle θB from the reference orientation. The angles θA and θB are equal and acute, for example, 4°.

[0121] There is a tendency that the visibility of the moiré fringe decreases as the pitch P3 between the first portion BA and the second portion BB along the second direction Y increases. In one example, the pitch P3 is 100 μm or more.

[0122] Figure 11 and Figure 12 It is a cross-sectional view showing another example of each light-shielding body constituting the louver portion 3 . Figure 11 and Figure 12 The examples shown are Figure 4 Compared with the example shown, the difference is that the light-shielding bodies B11, B21, B31, B41, and B51 each have a trapezoidal cross-section.

[0123] exist Figure 11 In the example shown, the cross-sectional shape of the light-shielding bodies B11 , B21 , B31 , B41 , and B51 is a forward tapered shape in which the width a decreases upward along the third direction Z.

[0124] exist Figure 12 In the example shown, the cross-sectional shape of the light-shielding bodies B11 , B21 , B31 , B41 , and B51 is an inverted tapered shape in which the width a increases upward along the third direction Z.

[0125] The light-blocking bodies B11 , B21 , B31 , B41 , and B51 are each formed of, for example, a resin material, but the light-blocking body B11 may be formed of a metal material.

[0126] Furthermore, among the light-shielding bodies B11 , B21 , B31 , B41 , and B51 , some may have forward tapered cross-sectional shapes, while others may have inverted tapered cross-sectional shapes.

[0127] Figure 13 It is a cross-sectional view showing another example of each light-shielding body constituting the louver portion 3 . Figure 13 The example shown is similar to Figure 4Compared with the example shown, the difference is that at least one of the light-shielding bodies B11, B21, B31, B41, and B51 has a cross section that is narrowed in the middle portion.

[0128] exist Figure 13 In the example shown, light shielding body B11 is formed of a metal material (e.g., molybdenum-tungsten alloy), while light shielding bodies B21, B31, B41, and B51 are each formed of a resin material. Light shielding bodies B21, B31, B41, and B51 each have the same thickness T21, T31, T41, and T51, for example, 2 μm. Light shielding body B11 is thinner than light shielding bodies B21, B31, B41, and B51. That is, thickness T11 is smaller than thickness T21, for example, less than 1 μm.

[0129] If we focus on the light shielding body B21, the light shielding body B21 has a lower portion BL2, an upper portion BU2, and a middle portion BM2. The lower portion BL2 is the portion facing the first transparent substrate 1 or the organic insulating film I1. The upper portion BU2 is the portion facing the first transparent substrate 1 or the organic insulating film I1. Figure 4 The middle portion BM2 is a portion between the lower portion BL2 and the upper portion BU2.

[0130] The width aL2 of the lower portion BL2 is the same as the width aU2 of the upper portion BU2. However, the width aL2 may be smaller than the width aU2 or may be larger than the width aU2.

[0131] The width aM2 of the middle portion BM2 is smaller than either the width aL2 or the width aU2.

[0132] Furthermore, when the shapes of the light-blocking bodies B21 , B31 , B41 , and B51 are compared, the width of the middle portion tends to increase as the distance from the light-blocking body B11 increases.

[0133] For example, when the light-blocking body B21 and the light-blocking body B31 are compared, the width aM2 of the middle portion BM2 of the light-blocking body B21 is smaller than the width aM3 of the middle portion BM3 of the light-blocking body B31 .

[0134] In addition, the width in the description here corresponds to the length along the first direction X.

[0135] Figure 14 It is a diagram for explaining the opening ratio of the louver portion 3 .

[0136] The light-shielding bodies B21, B31, B41, and B51 are respectively located directly above the light-shielding body B11, and the light-shielding bodies B22, B32, B42, and B52 are respectively located directly above the light-shielding body B12.

[0137] When the width of light shielding body B11 is a and the interval between light shielding body B11 and light shielding body B12 is b, the aperture ratio of louver 3 can be defined as (b / (a+b)). Width a is preferably greater than 3 μm, interval b is preferably greater than 10 μm, and the aperture ratio is preferably greater than 60%.

[0138] Figure 15 It is a diagram for explaining the thickness c of the louver portion 3 .

[0139] Here, it is assumed that the louver 3 is composed of five light-shielding layers B1 to B5 , and the length along the third direction Z from the lower surface of the lowest light-shielding layer B1 to the upper surface of the uppermost light-shielding layer B5 is defined as the thickness c of the louver 3 .

[0140] In the figure, dotted lines indicate a light path R1 between the light blocking body B11 and the light blocking body B12, passing near the light blocking body B11 and reaching the light blocking body B52, and a light path R2 emitted from the louver portion 3 into the air.

[0141] When the refractive index of the organic insulating film covering the light-shielding layers B1 to B5 is set to n1, the refractive index of air is set to n2, the angle formed by the light path R1 relative to the normal N of the first transparent substrate 1 is set to θ1, and the angle formed by the light path R2 relative to the normal N is set to θ2, the relationship shown in formula (1) in the figure holds between them.

[0142] In equation (1), sinθ1 is expressed as equation (2) in the figure. Substituting equation (2) into equation (1) and solving for c, the relationship in equation (3) holds. That is, the thickness c of the louver 3 is set based on equation (3). Here, angle θ2 is the lower limit of the angle between the light beam to be shielded and the normal line N.

[0143] Next, the spacing c' between the plurality of light-shielding layers B1 to B5 along the third direction Z will be described. For example, the dashed line in the figure indicates light path R3, which passes between light-shielding bodies B42 and B52 and reaches light-shielding body B52, in a light path parallel to light path R1. In order for light shielding bodies B42 or B52 to block light passing through light path R3, the spacing c' must satisfy the relationship of equation (4) in the figure.

[0144] The number of light shielding layers constituting the louver portion 3 is determined based on the interval c′ and the interval b.

[0145] According to the present embodiment described above, a liquid crystal device for viewing angle control that can achieve thickness reduction and a display device including the liquid crystal device can be provided.

[0146] Based on the liquid crystal devices described above as embodiments of the present invention, any liquid crystal devices that can be implemented by appropriately changing the design of a liquid crystal device by a person skilled in the art also fall within the scope of the present invention as long as they include the gist of the present invention.

[0147] Within the scope of the present invention, those skilled in the art can conceive of various variations, which are also interpreted as falling within the scope of the present invention. For example, with respect to the above-mentioned embodiments, embodiments obtained by those skilled in the art by appropriately adding, deleting, or changing the design of structural elements, or by adding, omitting, or changing the conditions of processes, are also included within the scope of the present invention as long as they have the gist of the present invention.

[0148] In addition, regarding other effects brought about by the methods described in the above embodiments, effects that can be understood from the description of this specification, or effects that can be appropriately thought of by those skilled in the art, are of course also interpreted as effects brought about by the present invention.

Claims

1. A liquid crystal device comprising: a first transparent substrate; a plurality of first light-shielding bodies, each formed in a strip shape and arranged at a first pitch on the inner surface of the first transparent substrate; a transparent first organic insulating film covering the plurality of first light-shielding bodies; a plurality of second light-shielding bodies, respectively overlapping the first light-shielding bodies and formed into strips parallel to the first light-shielding bodies; a transparent second organic insulating film covering the plurality of second light-shielding bodies; a plurality of third light-shielding bodies, respectively overlapping the second light-shielding bodies and formed into strips parallel to the second light-shielding bodies; a transparent third organic insulating film covering the plurality of third light-shielding bodies; an overcoat layer disposed above the third organic insulating film; a plurality of first electrodes, each formed in a strip shape, arranged on the outer coating layer at a second pitch smaller than the first pitch; a first alignment film covering the plurality of first electrodes; a second transparent substrate; a second electrode disposed on the inner surface of the second transparent substrate and facing the plurality of first electrodes; a second alignment film, covering the second electrode; as well as a liquid crystal layer disposed between the first alignment film and the second alignment film, The second light-shielding body and the third light-shielding body each have a lower portion facing the first transparent substrate, an upper portion facing the liquid crystal layer, and an intermediate portion between the lower portion and the upper portion. The width of the middle portion is smaller than the width of the lower portion and the width of the upper portion, The width of the lower portion is the same as the width of the upper portion.

2. The liquid crystal device according to claim 1, wherein The first light-blocking body, the second light-blocking body, and the third light-blocking body are formed of a resin material and have the same thickness.

3. The liquid crystal device according to claim 1, wherein The first organic insulating film, the second organic insulating film, and the third organic insulating film have the same thickness. The overcoat layer is thinner than the first organic insulating film.

4. The liquid crystal device according to claim 3, wherein The liquid crystal layer is thicker than the first organic insulating film.

5. The liquid crystal device according to claim 4, wherein The thickness of the liquid crystal layer is greater than 10 μm. The liquid crystal device according to claim 1 , wherein: The first electrode intersects the first light-blocking body in a plan view.

7. The liquid crystal device according to claim 1, wherein The first light shielding body is formed of a metal material. The second light-shielding body and the third light-shielding body are formed of a resin material. The first light-blocking body is thinner than the second light-blocking body and the third light-blocking body.

8. The liquid crystal device according to claim 7, wherein The width of the middle portion of the second light-blocking body is smaller than the width of the middle portion of the third light-blocking body.

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