Display device

Abstract

A display device according to an embodiment includes: an array substrate; the opposite substrate is opposite to the array substrate; the liquid crystal layer is arranged between the array substrate and the opposite substrate; a transparent first cover member having a first main surface facing the facing substrate, a second main surface on the opposite side to the first main surface, and a first side surface extending in a first direction; and a light source that irradiates light to the first side surface in a second direction that intersects the first direction. When viewed in the first direction, the first side surface is a curved surface which connects the first main surface and the second main surface and protrudes toward the light source.

Description

[0001] This application is based upon and claims the benefit of priority from Japanese patent application No. 2023-029613 filed on February 28, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] An embodiment of the utility model relates to a display device. Background Art

[0003] In recent years, a display device having a display panel having a polymer dispersed liquid crystal layer (PDLC), a light source, etc. has been proposed. The polymer dispersed liquid crystal layer can switch between a scattering state in which light is scattered and a transparent state in which light is transmitted. By switching the display panel to the scattering state, the display device can display an image. On the other hand, by switching the display panel to the transparent state, the user can visually confirm the background through the display panel. Utility Model Content

[0004] In general, a display device according to an embodiment includes: an array substrate; an opposing substrate opposite to the array substrate; a liquid crystal layer provided between the array substrate and the opposing substrate; a transparent first cover member having a first main surface opposite to the opposing substrate, a second main surface opposite to the first main surface, and a first side surface extending along a first direction; and a light source irradiating light toward the first side surface along a second direction intersecting the first direction. When viewed along the first direction, the first side surface is a curved surface connecting the first main surface and the second main surface and convex toward the light source.

[0005] According to this configuration, a display device capable of improving display quality can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a diagram showing a configuration example of a display device according to the first embodiment.

[0007] Figure 2 It is a schematic cross-sectional view of a display device.

[0008] Figure 3 Yes means including Figure 2 The first cover member and the second cover member are shown in a schematic plan view of the display device.

[0009] Figure 4 It is along Figure 3 A schematic cross-sectional view of the display device taken along line IV-IV is shown.

[0010] Figure 5 It is along Figure 3A schematic cross-sectional view of the display device taken along line VV is shown.

[0011] Figure 6 It is a cross-sectional view showing the light-reflecting side of the display device in an enlarged manner.

[0012] Figure 7 It is a diagram for explaining the propagation of light in a display device of a comparative example.

[0013] Figure 8 It is a diagram for explaining the propagation of light in the display device according to the first embodiment.

[0014] Fig. 9 This is a diagram showing measurement points of brightness intensity in the simulation.

[0015] Fig.10 It is a diagram for explaining another example of the reflecting member.

[0016] Fig.11 It is a diagram for explaining still another example of the reflecting member.

[0017] Fig.12 It is a diagram for explaining still another example of the reflecting member.

[0018] Fig.13 It is a schematic cross-sectional view of a display device according to a second embodiment.

[0019] Fig.14 It is a schematic cross-sectional view of a display device according to a third embodiment.

[0020] Fig.15 It is a schematic cross-sectional view of a display device according to a third embodiment.

[0021] Fig.16 It is a schematic cross-sectional view of a display device according to a fourth embodiment. DETAILED DESCRIPTION

[0022] The following describes various embodiments of the present invention with reference to the accompanying drawings. This application is only an example, and appropriate changes that can be easily thought of by those skilled in the art while maintaining the spirit of the invention are of course also included in the scope of the present invention.

[0023] In addition, the drawings sometimes schematically show the width, thickness, shape, etc. of each part compared with the actual mode in order to make the description clearer, but this is only an example and does not limit the interpretation of the present invention. In each figure, the reference numerals are sometimes omitted for the same or similar elements arranged continuously.

[0024] In addition, in this specification and each figure, with respect to the figures which have already appeared, the same figure mark is attached|subjected to the component which is the same as or performs a similar function as the above-mentioned component, and the repeated detailed description may be appropriately omitted.

[0025] In addition, in the drawings, mutually orthogonal X-axis, Y-axis, and Z-axis are described as necessary to facilitate understanding. The direction along the X-axis is called the first direction X, the direction along the Y-axis is called the second direction Y, and the direction along the Z-axis is called the third direction Z. Observing various elements parallel to the third direction Z is called a top view.

[0026] In this embodiment, a highly light-transmitting liquid crystal display device (so-called transparent display device) using polymer-dispersed liquid crystal is disclosed as an example of a display device. However, the configuration disclosed in this embodiment can also be applied to other types of display devices.

[0027] [First embodiment]

[0028] Figure 1 1 is a diagram showing a configuration example of a display device DSP according to the first embodiment. The display device DSP includes a display panel PNL, a light source unit LU, and a light guide LG. Figure 1 In FIG. 1 , a part of the light source unit LU and the light guide LG is provided with a breaking line and a part is omitted.

[0029] The display panel PNL includes an array substrate AR and a counter substrate CT which overlap each other in the third direction Z. The counter substrate CT faces the array substrate AR. Figure 1 In the figure, the shapes of the array substrate AR and the counter-substrate CT in a plan view are both rectangular shapes that are long in the first direction X. However, the shapes of the array substrate AR and the counter-substrate CT are not limited to this example.

[0030] The width of the array substrate AR in the second direction Y is greater than the width of the counter substrate CT in the second direction Y. Thus, the array substrate AR has a mounting area MA that does not overlap with the counter substrate CT. A flexible circuit substrate and an integrated circuit described later are mounted in the mounting area MA.

[0031] The display panel PNL includes a display area DA for displaying an image and a frame-shaped peripheral area SA surrounding the display area DA. The display area DA and the peripheral area SA are both formed in the overlapping portion of the array substrate AR and the counter substrate CT. The display area DA includes a plurality of pixels PX arranged in a matrix in a first direction X and a second direction Y.

[0032] The display panel PNL further includes a liquid crystal layer LC sealed between the array substrate AR and the counter substrate CT. Figure 1As shown schematically and enlarged below, the liquid crystal layer LC is composed of a polymer dispersed liquid crystal including a polymer 31 and liquid crystal molecules 32. In one example, the polymer 31 is a liquid crystal polymer. The polymer 31 is formed into a rib shape extending along the first direction X and is arranged in the second direction Y. The liquid crystal molecules 32 are dispersed in the gaps between the polymers 31 and are oriented so that their long axes are along the first direction X.

[0033] The polymer 31 and the liquid crystal molecules 32 have optical anisotropy or refractive index anisotropy, respectively. The responsiveness of the polymer 31 to the electric field is lower than that of the liquid crystal molecules 32 to the electric field. In one example, the orientation direction of the polymer 31 hardly changes regardless of the presence or absence of the electric field. On the other hand, the orientation direction of the liquid crystal molecules 32 changes according to the voltage applied to the liquid crystal layer LC.

[0034] When no voltage is applied to the liquid crystal layer LC, the optical axes of the polymer 31 and the liquid crystal molecules 32 are parallel to each other, and light incident on the liquid crystal layer LC is transmitted through the liquid crystal layer LC without being scattered (transparent state).

[0035] When a voltage is applied to the liquid crystal layer LC, the optical axes of the polymer 31 and the liquid crystal molecules 32 intersect with each other, and light incident on the liquid crystal layer LC is scattered in the liquid crystal layer LC (scattering state). That is, the liquid crystal layer LC can switch between a transparent state and a scattering state according to an applied voltage.

[0036] As in Figure 1 As shown in the enlarged form above, a plurality of scanning lines G and a plurality of signal lines S are arranged in the display area DA. The plurality of scanning lines G extend along the first direction X and are arranged in the second direction Y. The plurality of signal lines S extend along the second direction Y and are arranged in the first direction X.

[0037] Each pixel PX includes a switching element SW, a pixel electrode PE, a common electrode CE, and a capacitor CS. The switching element SW is formed of, for example, a thin film transistor (TFT), and is electrically connected to the scanning line G and the signal line S. The pixel electrode PE is electrically connected to the switching element SW.

[0038] The liquid crystal layer LC (particularly the liquid crystal molecules 32) is driven by an electric field generated between the pixel electrode PE and the common electrode CE. The capacitor CS is formed between, for example, an electrode having the same potential as the common electrode CE and an electrode having the same potential as the pixel electrode PE.

[0039] The light source unit LU and the light guide LG are arranged in the mounting area MA along the first direction X. The light source unit LU includes a plurality of light sources LS arranged in the first direction X. Each light source LS irradiates light to the light guide LG. As the light guide LG, for example, a lens such as a prism lens can be used.

[0040] The plurality of light sources LS include, for example, a light emitting element emitting red light, a light emitting element emitting green light, and a light emitting element emitting blue light. These light emitting elements may be arranged in a first direction X or stacked in a third direction Z. As the light emitting element, an LED (Light Emitting Diode) may be used.

[0041] Figure 2 1 is a schematic cross-sectional view of the display device DSP. The structure of the display panel PNL and the like is schematically shown in this figure, and elements such as the scanning lines G, the signal lines S, and the switching elements SW are omitted.

[0042] The array substrate AR is bonded to the counter substrate CT via a sealing material SE. The sealing material SE has a shape surrounding the display area DA in a plan view. The liquid crystal layer LC is sealed in a space surrounded by the sealing material SE.

[0043] The array substrate AR includes the above-mentioned pixel electrode PE. The counter substrate CT includes the above-mentioned common electrode CE. The pixel electrode PE and the common electrode CE are opposite to each other via the liquid crystal layer LC. In addition, the configuration of the pixel electrode PE and the common electrode CE is not limited to this example. As another example, the array substrate AR may also include both the pixel electrode PE and the common electrode CE.

[0044] The array substrate AR has a main surface F1, a main surface F2 on the opposite side of the main surface F1, and side surfaces E1a and E1b connecting the main surface F1 and the main surface F2. The counter substrate CT has a main surface F3, a main surface F4 on the opposite side of the main surface F3, and side surfaces E2a and E2b connecting the main surface F3 and the main surface F4. The main surface F3 is opposite to the main surface F2 via the liquid crystal layer LC.

[0045] The display panel PNL further includes a first cover member CM1 and a second cover member CM2. The first cover member CM1 and the second cover member CM2 are both transparent, and in one example, are cover glasses formed of glass. Alternatively, the first cover member CM1 and the second cover member CM2 may be formed of a transparent resin material such as plastic.

[0046] The first cover component CM1 has, for example, the same thickness as the second cover component CM2. Here, the thickness refers to the distance along the third direction Z. The thickness of the first cover component CM1 and the second cover component CM2 is sufficiently greater than the thickness of the array substrate AR and the counter substrate CT. In one example, the first cover component CM1 and the second cover component CM2 have a thickness that is more than twice the thickness of the array substrate AR and the counter substrate CT.

[0047] The first cover part CM1 has a main surface F5 opposite to the main surface F4, a main surface F6 on the opposite side of the main surface F5, and side surfaces E3a and E3b connecting the main surface F5 and the main surface F6. In this embodiment, the main surface F5 is equivalent to the first main surface, the main surface F6 is equivalent to the second main surface, the side surface E3a is equivalent to the first side surface, and the side surface E3b is equivalent to the second side surface.

[0048] The main surface F4 is bonded to the main surface F5 via a transparent first adhesive layer AD1. As the first adhesive layer AD1, for example, OCA (Optical Clear Adhesive) can be used.

[0049] The second cover part CM2 has a main surface F7 opposite to the main surface F1, a main surface F8 on the opposite side of the main surface F7, and side surfaces E4a and E4b connecting the main surface F7 and the main surface F8. In this embodiment, the main surface F7 is equivalent to the third main surface, the main surface F8 is equivalent to the fourth main surface, the side surface E4a is equivalent to the fourth side surface, and the side surface E4b is equivalent to the third side surface.

[0050] The main surface F1 is bonded to the main surface F7 via a transparent second adhesive layer AD2. As the second adhesive layer AD2, OCA can be used similarly to the first adhesive layer AD1.

[0051] The side surfaces E1a, E2a, E3a, and E4a are all located on the light source LS side (light incident side), and the side surfaces E1b, E2b, E3b, and E4b are all located on the side opposite to the light source LS (anti-light incident side).

[0052] The mounting area MA is formed in a portion of the array substrate AR that protrudes from the side surface E2a. The side surface E4b is, for example, located directly below the side surface E3b. The side surface E4a is, for example, provided at a position that protrudes in a direction opposite to the second direction Y from the side surface E1a.

[0053] The display panel PNL further includes a reflective member RF1. The reflective member RF1 is disposed near the side surfaces E1b, E2b, E3b, and E4b. In other words, the reflective member RF1 is disposed on the opposite side of the light source unit LU across the first cover member CM1 when viewed from above. The reflective member RF1 is, for example, a reflective tape attached to the side surfaces E1b, E2b, E3b, and E4b.

[0054] The light source LS is opposite to the side surface E3a. The light guide LG is disposed between the side surface E3a and the light source LS. Figure 2 An example of the path of the light L emitted from the light source LS is shown in FIG.

[0055] The light source LS irradiates light along the second direction Y. Specifically, the light source LS irradiates light toward the side surface E3a. The light L emitted from the light source LS passes through the light guide LG and is incident on the side surface E3a. The light L is emitted toward the light-reflecting side while being repeatedly totally reflected between the main surface F6 and the main surface F8. The light L reaching the side surfaces E1b, E2b, E3b, and E4b is reflected by the reflective component RF1 and is emitted toward the light-incident side while being repeatedly totally reflected between the main surface F6 and the main surface F8.

[0056] In the vicinity of the pixel PX in the transparent state, the light L is hardly scattered in the liquid crystal layer LC, and therefore, the light L hardly leaks to the outside of the first cover member CM1 and the second cover member CM2.

[0057] On the other hand, near the pixel PX in the scattering state, the light L is scattered in the liquid crystal layer LC. The scattered light SL is emitted from the first cover part CM1 and the second cover part CM2 and visually recognized by the user as a display image. By gradually regulating the voltage applied to the pixel electrode PE within a prescribed range, grayscale expression of the scattering degree (brightness) can also be achieved.

[0058] In addition, near the pixel PX in the transparent state, the external light incident on the first cover part CM1 and the second cover part CM2 passes through the liquid crystal layer LC without being scattered. That is, when the display device DSP is observed from the first cover part CM1 side, the background on the second cover part CM2 side can be visually confirmed, and when the display device DSP is observed from the second cover part CM2 side, the background on the first cover part CM1 side can be visually confirmed.

[0059] For example, as a method for the display device DSP to display images, a field sequential method can be used, which repeatedly lights up the red light-emitting elements in the multiple light sources LS to display a first subframe of a red image, lights up the green light-emitting elements to display a second subframe of a green image, and lights up the blue light-emitting elements to display a third subframe of a blue image.

[0060] Figure 3 Yes means including Figure 2 The first cover member CM1 and the second cover member CM2 are shown in a schematic plan view of the display device DSP.

[0061] First, an example of a configuration that can be applied near the mounting area MA is described. The display device DSP further includes a frame FM that holds the light source unit LU and the light guide LG. The frame FM has a shape that is long in the first direction X, covers the mounting area MA, and overlaps a portion of the second cover member CM2. Figure 3 In the example shown, there are ribs RI extending in the first direction X, and a plurality of openings OP.

[0062] One ends of a plurality of flexible circuit boards FPC are connected to the mounting area MA, and the other ends of the flexible circuit boards FPC are connected to a circuit board PCB, which is a rigid printed circuit board, for example.

[0063] Next, the first cover member CM1 and the second cover member CM2 will be described.

[0064] exist Figure 3 In the example shown, the planar shapes of the counter-substrate CT and the first cover member CM1 are identical. The second cover member CM2 has a greater width in the first direction X than the array substrate AR, the counter-substrate CT, and the first cover member CM1.

[0065] Thus, both ends of the second cover member CM2 in the first direction X protrude from the array substrate AR, the counter-substrate CT, and the second cover member CM2. The both ends of the second cover member CM2 can be used to install a frame to protect both sides of the display panel PNL in the first direction X.

[0066] The first cover member CM1 further has side surfaces E3c and E3d. In the present embodiment, the side surface E3c corresponds to the fifth side surface, and the side surface E3d corresponds to the sixth side surface. The side surfaces E3c and E3d connect the main surface F5 and the main surface F6.

[0067] The side surfaces E3a and E3b extend along the first direction X and are arranged in the second direction Y. The side surfaces E3a and E3b are arranged, for example, in this order in the second direction Y. The side surfaces E3c and E3d extend along the second direction Y and are arranged in the first direction X. The side surfaces E3c and E3d are arranged, for example, in this order in the first direction X.

[0068] The second cover member CM2 further has side surfaces E4c and E4d. In the present embodiment, the side surface E4c corresponds to the seventh side surface, and the side surface E4d corresponds to the eighth side surface. The side surfaces E4c and E4d connect the main surface F7 and the main surface F8.

[0069] The side surfaces E4a and E4b extend along the first direction X and are arranged in the second direction Y. The side surfaces E4a and E4b are arranged, for example, in this order in the second direction Y. The side surfaces E4c and E4d extend along the second direction Y and are arranged in the first direction X. The side surfaces E4c and E4d are arranged, for example, in this order in the first direction X.

[0070] like Figure 3 As shown, the side surface E4c is provided at a position protruding in a direction opposite to the first direction X compared to the side surface E3c, and the side surface E4d is provided at a position protruding in the first direction X compared to the side surface E4c. The reflecting member RF1 is provided along the first direction X.

[0071] Next, use Figure 4 as well as Figure 5 A structure applicable to the first cover member CM1 and the second cover member CM2 will be described.

[0072] Figure 4 It is along Figure 3 A schematic cross-sectional view of the display device DSP taken along line IV-IV is shown. Figure 5 It is along Figure 3 A schematic cross-sectional view of the display device DSP taken along line VV is shown. Figure 4 In the cross section of the display device DSP observed along the first direction X, Figure 5 , the cross section of the display device DSP is viewed along the second direction Y. The first cover member CM1 has the side surfaces E3a, E3b, E3c, and E3d as described above.

[0073] like Figure 4 As shown, the side surfaces E3a and E3b are convex curved surfaces connecting the main surface F5 and the main surface F6. Specifically, the side surface E3a is a curved surface convex in the direction opposite to the second direction Y, and the side surface E3b is a curved surface convex in the second direction Y.

[0074] In other words, the side surfaces E3a and E3b have a cross-sectional shape of an arc. The cross-sectional shape of the side surfaces E3a and E3b can also be said to be an R shape. The side surfaces E3a and E3b extend along the first direction X in the cross-sectional shape described above. From the perspective of the light source LS, the side surface E3a is a curved surface convex toward the light source LS, and the side surface E3b is a curved surface convex away from the light source LS.

[0075] like Figure 5 As shown, the side surfaces E3c and E3d are convex curved surfaces connecting the main surface F5 and the main surface F6. Specifically, the side surface E3c is a curved surface convex in the direction opposite to the first direction X, and the side surface E3d is a curved surface convex in the first direction X. In other words, the side surfaces E3c and E3d have a cross-sectional shape of an arc. The side surfaces E3c and E3d extend along the second direction Y in the cross-sectional shape described above.

[0076] As described above, the second cover member has side surfaces E4a, E4b, E4c, and E4d. Figure 4 As shown, the side surfaces E4a and E4b are convex curved surfaces connecting the main surface F7 and the main surface F8.

[0077] Specifically, the side surface E4a is a curved surface convex in the direction opposite to the second direction Y, and the side surface E4b is a curved surface convex in the second direction Y. In other words, the side surfaces E4a and E4b have a circular arc cross-sectional shape. The side surfaces E4a and E4b extend in the first direction X in the above-mentioned cross-sectional shape.

[0078] like Figure 5 As shown, the side surfaces E4c and E4d are convex curved surfaces connecting the main surface F7 and the main surface F8. Specifically, the side surface E4c is a curved surface convex in the direction opposite to the first direction X, and the side surface E4d is a curved surface convex in the first direction X. In other words, the side surfaces E4c and E4d have a cross-sectional shape of an arc. The side surfaces E4c and E4d extend along the second direction Y in the cross-sectional shape described above.

[0079] As described above, in the present embodiment, the side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d are all formed as convex curved surfaces. In the present embodiment, the side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d have the same surface properties. Here, the side surface E3a of the first cover part CM1 is further described, but the side surfaces E3b, E3c, E3d, E4a, E4b, E4c, E4d are also formed in the same manner.

[0080] like Figure 4 As shown, the side surface E3a is a convex curved surface. The side surface E3a has a uniform radius of curvature R in the first direction X. The center C1 of the radius of curvature R is located, for example, at the center of the thickness of the first cover part CM1.

[0081] The radius of curvature R of the side surface E3a is, for example, smaller than the thickness of the first cover component CM1. The radius of curvature R of the side surface E3a is, for example, larger than the thickness of the array substrate AR and the counter substrate CT. When the thickness of the first cover component CM1 is 2.75 mm, the radius of curvature R of the side surface E3a is, for example, greater than 2.0 mm and less than 2.5 mm, and is 2.5 mm in one example. The radius of curvature R of the side surface E3a can be appropriately changed according to the thickness of the first cover component CM1, etc.

[0082] Next, the surface properties of the side surface E3a will be described.

[0083] In one example, the side surface E3a may be formed as a mirror surface. A mirror surface is, for example, a smooth surface with almost no irregularities. The side surface E3a is formed by, for example, grinding after CNC processing or the like.

[0084] In this case, from the viewpoint of parameters defined in JIS B 0601: 2013, the arithmetic mean roughness Ra of the side surface E3a is, for example, 0.02 μm or less, and the maximum height roughness Rz of the side surface E3a is, for example, 0.2 μm or less. The parameters of the side surface E3a when formed into a mirror surface are not limited to the above examples.

[0085] In other examples, the side surface E3a may also be formed as a rough surface. The rough surface refers to, for example, a surface with fine and random concave and convex shapes. In other words, the side surface E3a is formed in a frosted glass shape. The side surface E3a is formed by CNC processing or the like. The side surface E3a has, for example, a surface texture that is rougher than the main surfaces F5 and F6.

[0086] In this case, from the perspective of the parameters specified in JIS B 0601, the arithmetic mean roughness Ra of the side surface E3a is, for example, 0.1 μm or more and 0.5 μm or less, and the maximum height roughness Rz of the side surface E3a is, for example, 1.5 μm or more and 9.5 μm or less. In addition, the parameters of the side surface E3a when formed into a frosted glass shape are not limited to the above examples.

[0087] like Figure 4 As shown, reflection tapes TP1 and TP2 are provided on the upper surface and the lower surface of the light guide LG, respectively.

[0088] Figure 6 1 is an enlarged cross-sectional view showing the light-reflecting side of the display device DSP. The reflecting component RF1 is provided from the side surface E3b to the side surface E4b. Figure 6 In the example shown, it is not provided on the entire side surface E3b and the side surface E4d.

[0089] In other words, the side surface E3b has a portion P1 that does not overlap with the reflective component RF1 in the second direction Y, and the side surface E4b has a portion P2 that does not overlap with the reflective component RF1 in the second direction Y. The portion P1 is located on the principal surface F6 side of the side surface E3b, and the portion P2 is located on the principal surface F8 side of the side surface E4b. The length of the portion P1 and the portion P2 in the third direction Z is, for example, 0.5 mm.

[0090] Next, the propagation of light on the light incident side and the light anti-incident side of the display panel PNL will be described. Figure 7 It is a diagram for explaining the propagation of light in the display device DSP10 of the comparative example. Figure 8 1 is a diagram for explaining the propagation of light in the display device DSP of this embodiment. Figure 7 as well as Figure 8 Some elements such as the display panel PNL and the light guide LG are omitted.

[0091] The display device DSP10 of the comparative example includes a first cover member CM10. The first cover member CM10 has side surfaces E30a and E30b. The side surface E30a corresponds to the side surface on the light incident side, and the side surface E30b corresponds to the side surface on the anti-light incident side.

[0092] The side surfaces E30a and E30b are not curved surfaces but are planes parallel to an XZ plane defined by the first direction X and the third direction Z. Elements other than the first cover member CM10 constituting the display device DSP10 are the same as those of the display device DSP.

[0093] First, the light incident side is described. Figure 7 as well as Figure 8 , the propagation of light emitted from the light source LS provided at the same position is shown.

[0094] exist Figure 7 In the diagram, light incident on the first cover member CM10 from the side surface E30a travels in the second direction Y while repeatedly being reflected at the interface between the first cover member CM10 and the air layer and at the interface between the second cover member (not shown) and the air layer.

[0095] like Figure 7 As shown in FIG. 1 , the angle formed between the light incident from the side surface E30a and the main surface F60 and the light traveling toward the main surface F60 of the first cover member CM10 is defined as angle θ1. Figure 8 In FIG. 5 , an angle formed between the light that enters from the side surface E3a and travels toward the main surface F6 of the first cover member CM1 and the main surface F6 is defined as an angle θ2.

[0096] As described above, the side surface E3a of the first cover member CM1 is a curved surface convex toward the light source LS. The light emitted from the light source LS is refracted at the side surface E3a and enters the first cover member CM1, so the angle θ2 becomes smaller than the angle θ1.

[0097] As the angle θ2 decreases, the number of times that light traveling in the second direction Y is totally reflected between the main surfaces F6 and F8 decreases. In other words, the number of times that light passes through the liquid crystal layer LC per unit length in the second direction Y is less in display device DSP than in display device DSP10.

[0098] As light passes through the array substrate AR and the counter substrate CT, it is scattered in the liquid crystal layer LC or absorbed and scattered by wiring of the array substrate AR, etc. These may cause the light emitted from the light source LS to weaken as it travels toward the light-reflecting side.

[0099] According to this embodiment, the number of times light passes through the liquid crystal layer LC on the light incident side is reduced, so that light propagating in the second direction Y is less likely to become weak. In other words, compared with the comparative example, stronger light can be transmitted to the opposite light incident side.

[0100] Next, the light reflection side will be described.

[0101] like Figure 7As shown, in the display device DSP10 of the comparative example, when light traveling in the second direction Y reaches the light-returning side and is reflected by the reflective member RF1 , the light travels in the direction opposite to the second direction Y.

[0102] On the other hand, Figure 8 As shown, in the display device DSP of this embodiment, if the light traveling along the second direction Y reaches the light-reflecting side, the light is refracted at the side surface E3b before and after being reflected by the reflective component RF1. Thus, the light is converted into light traveling toward the liquid crystal layer LC. As a result, on the light-reflecting side, the light incident on the liquid crystal layer LC increases, and the brightness of the light-reflecting side can be increased.

[0103] Fig. 9 is a diagram showing the measurement points of the brightness intensity in the simulation. Fig. 9 In FIG. 1 , the first cover part CM1 is shown, and other elements of the display device DSP are omitted. Fig. 9 , the first cover part CM1 is shown in a plan view.

[0104] The conditions in the simulation are as follows.

[0105] The measuring points A, B, and C are located at the center of the width of the first cover part CM1 in the first direction X. The distance D1 from the side surface E3a to the measuring point A is 57 mm, the distance D2 from the side surface E3a to the measuring point B is 130 mm, and the distance D3 from the side surface E3a to the measuring point C is 216 mm. The measuring point B corresponds to the center of the width of the display area DA in the second direction Y. The distance from the side surfaces E3a and E3b to the ends DA1 and DA2 of the display area DA is 3 mm.

[0106] The width of the first cover part CM1 in the second direction Y is 265.2 mm, the thickness of the first cover part CM1 is 2.75 mm, and the refractive index of the first cover part CM1 is 1.47.

[0107] The thickness of the second cover member CM2 is 2.75 mm, and the refractive index of the second cover member CM2 is 1.47. The distance from the side surface E4a of the second cover member CM2 to the end DA1 of the display area DA is 28.7 mm.

[0108] The side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d are all convex curved surfaces. The side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d have the same surface properties.

[0109] The transparent substrate of the array substrate AR has a thickness of 0.5 mm and a refractive index of 1.51. The switch element SW and the pixel electrode PE ( Figure 1 The thickness of the transparent substrate of the counter substrate CT is 0.7 mm, and the refractive index of the transparent substrate is 1.51. A common electrode CE ( Figure 1 shown).

[0110] The thickness of the first adhesive layer AD1 and the second adhesive layer AD2 are 0.125 mm, and the refractive index of the first adhesive layer AD1 and the second adhesive layer AD2 are 1.47, respectively. The thickness of the light guide LG is 2.4 mm, and the thickness of the reflective tapes TP1 and TP2 are both 0.21 mm.

[0111] In this way, the refractive indexes of the transparent substrate of the array substrate AR, the transparent electrode of the counter substrate CT, the first adhesive layer AD1, the second adhesive layer AD2, the first cover component CM1, and the second cover component CM2 are all the same. In addition, the "same" here is not limited to the case where the difference in refractive index is zero, but includes the case where the difference in refractive index is less than 0.05.

[0112] In the simulation, the curvature radii of the side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d were changed into 2.0 mm, 2.25 mm and 2.5 mm. The centers of the curvature radii were located at the centers of the thicknesses of the first cover part CM1 and the second cover part CM2, respectively.

[0113] Among them, when the curvature radius is 2.5 mm, the position of the center of the curvature radius changes by 0.2 mm along the third direction Z (expressed as "+0.2" in Table 1), and changes by 0.2 mm in the direction opposite to the third direction Z (expressed as "-0.2" in Table 1).

[0114] In the simulation, the surface properties of the side surfaces E3a, E3b, E3c, and E3d and the side surfaces E4a, E4b, E4c, and E4d were changed into two types: a mirror surface and a rough surface.

[0115] Table 1 is a table showing the simulation results. The brightness of the screen becomes darker from the light incident side to the anti-light incident side, which is called brightness gradient. The brightness gradient is calculated by the ratio of the brightness intensities at the measurement points A, B, and C calculated under the above conditions.

[0116] Table 1

[0117]

[0118]

[0119] The brightness gradient (C / A) refers to the ratio of the brightness intensity at the measurement point A to the brightness intensity at the measurement point C. The brightness gradient (B / A) refers to the ratio of the brightness intensity at the measurement point A to the brightness intensity at the measurement point B. The brightness gradient (C / B) refers to the ratio of the brightness intensity at the measurement point B to the brightness intensity at the measurement point C. The brightness gradient indicates that the smaller the value thereof, the smaller the change in brightness in the second direction Y. Therefore, the brightness gradient is preferably smaller in the display device.

[0120] In Table 1, as a comparative example, the case where the side surfaces E3a, E3b, E3c, and E3d and the side surfaces E4a, E4b, E4c, and E4d are flat surfaces is indicated as “no chamfer.” The surface property in this comparative example is a rough surface.

[0121] As shown in Table 1, by forming the side surfaces E3a, E3b, E3c, E3d and the side surfaces E4a, E4b, E4c, E4d into convex curved surfaces, the brightness gradient (C / A), brightness gradient (B / A) and brightness gradient (C / B) are overall reduced compared to the comparative example, confirming that the display quality of the display device DSP is improved.

[0122] In the brightness gradient (C / A), it was confirmed that it was reduced by 4 to 14% compared with the comparative example. In the brightness gradient (C / A), when the radius of curvature was 2.5 mm and the surface texture was a mirror surface, it was confirmed that the value of the brightness gradient was the smallest. From the perspective of surface texture, in the brightness gradient (C / A), it was confirmed that the value of the brightness gradient of the mirror surface was smaller than that of the rough surface.

[0123] In the brightness gradient (C / A), it was also confirmed that the value of the brightness gradient became smaller when the position of the center of the radius of curvature was changed. More specifically, it was confirmed that the value of the brightness gradient became smaller when the position of the center of the radius of curvature was changed in the direction opposite to the third direction Z, compared with the case where the position of the center of the radius of curvature was changed in the third direction Z. In this way, according to the brightness gradient (C / A) of the simulation result, it can also be confirmed that the light incident on the liquid crystal layer LC on the side opposite to the incident light increases.

[0124] If the display device DSP is constructed as described above, the display quality can be improved. More specifically, the display device DSP includes an array substrate AR, a counter substrate CT, a liquid crystal layer LC provided between the array substrate AR and the counter substrate CT, a first cover member CM1 having a side surface E3a, and a light source LS for irradiating light to the side surface E3a. The side surface E3a is a curved surface convex toward the light source LS when viewed along the first direction X.

[0125] If used Figure 7 as well as Figure 8As described above, by using the side surface E3a, the number of times that light passes through the liquid crystal layer LC on the light incident side is reduced, and the light propagating along the second direction Y is not easily weakened. Therefore, according to this embodiment, the brightness on the side opposite to the light incident side can be increased compared with the display device DSP10 of the comparative example. As a result, the brightness gradient is suppressed, and the display quality of the display device DSP can be improved.

[0126] The first cover part CM1 of this embodiment also has a side surface E3b which is a convex curved surface. By forming the side surfaces E3a and E3b connecting the main surface F5 and the main surface F6 into curved surfaces, the corners formed by the main surfaces F5 and F6 and the side surfaces E3a and E3b are not easily damaged, thereby improving the strength of the first cover part CM1.

[0127] Furthermore, in the present embodiment, both the side surfaces E3c and E3d connecting the main surface F5 and the main surface F6 are formed into curved surfaces. This can further improve the strength of the first cover member CM1.

[0128] If used Figure 7 as well as Figure 8 As described above, the side surface E3b increases the amount of light incident on the liquid crystal layer LC on the light-reflecting side. As a result, the brightness on the light-reflecting side increases, and the brightness gradient is suppressed. As a result, the display quality of the display device DSP can be further improved.

[0129] In this embodiment, the display device DSP further includes a second cover member CM2 having a side surface E4b as a convex curved surface. By using the side surface E4b, as with the side surface E3b, the light incident on the liquid crystal layer LC can be increased on the light-reflecting side. As a result, the brightness on the light-reflecting side can be further increased, and the brightness gradient can be suppressed. As a result, the display quality of the display device DSP can be further improved.

[0130] Moreover, in the second cover part CM2 of the present embodiment, the side surfaces E4a, E4b, E4c, and E4d connecting the main surface F7 and the main surface F8 are all formed into curved surfaces. The corners formed by the main surfaces F7 and F8 and the side surfaces E4a, E4b, E4c, and E4d are not easily damaged, which can improve the strength of the second cover part CM2.

[0131] According to this embodiment, the display quality in the display device DSP can be improved. In addition, according to this embodiment, the above-mentioned various effects can be obtained.

[0132] In addition, the reflective member is not limited to the above-mentioned example. Figures 10 to 12 It is a diagram for explaining another example of the reflecting member.

[0133] The reflective component RF1 is Fig.10In the example shown, it is provided on the entire side surface E3b and the entire side surface E4d. In other words, the entire side surface E3b overlaps with the reflective component RF1 in the second direction Y, and the entire side surface E4b overlaps with the reflective component RF1 in the second direction Y. Thus, since light is not easily leaked to the outside from the light-reflecting side, the light utilization efficiency can be improved.

[0134] exist Fig.11 In the example shown, the display device DSP includes reflecting members RF2 and RF3 instead of the reflecting member RF1. The reflecting member RF2 is provided on the entire side surface E3b, and the reflecting member RF3 is provided on the entire side surface E4d.

[0135] The reflective members RF2 and RF3 are, for example, reflective films. The reflective members RF2 and RF3 may be formed by coating a material having light reflectivity such as silver, or may be formed by vapor deposition of such a material. The reflective members RF2 and RF3 are not limited to these examples.

[0136] By providing the reflective component RF2 on the side E3b and the reflective component RF3 on the side E4d, it is difficult for light to leak out from the light-reflecting side. Fig.11 In the example shown, no reflective member is provided on the side surface E1 b of the array substrate AR and the side surface E2 b of the counter-substrate CT.

[0137] exist Fig.12 In the example shown, the reflective component RF1 and the reflective components RF2 and RF3 are all provided. Since the reflective component RF1 is provided on the side E1b of the array substrate AR and the side E2b of the counter substrate CT, Fig.11 Compared with the example shown in the figure, light is less likely to leak out from the light-reflecting side, thereby further improving the light utilization efficiency.

[0138] In addition, in the first cover part CM1, the side surfaces E3c and E3d may have surface properties different from those of the side surfaces E3a and E3b. By forming the side surfaces E3c and E3d into a frosted glass shape, light is diffused near the side surfaces E3c and E3d, thereby suppressing uneven display of the display area DA in the first direction X. The above example can also be applied to the second cover part CM2.

[0139] In the other embodiments and modifications described below, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and the detailed description thereof may be omitted or simplified.

[0140] [Second Embodiment]

[0141] Here, the second embodiment will be described. Here, the differences from the first embodiment will be mainly mentioned, but the same structure as that of the first embodiment can be applied to each part of the display device DSP of this embodiment.

[0142] Fig.13 FIG. 1 is a schematic cross-sectional view of the display device DSP of this embodiment. Fig.13 , the cross section of the display device DSP is observed along the second direction Y. In this embodiment, the side surfaces E3c and E3d of the first cover part CM1 and the side surfaces E4c and E4d of the second cover part CM2 are different from those in the first embodiment. The side surfaces E3a and E3b of the first cover part CM1 and the side surfaces E4a and E4b of the second cover part CM2 have the same Figure 4 The examples shown are of the same construction.

[0143] like Fig.13 As shown, the first cover part CM1 has side surfaces E3c and E3d. The side surfaces E3c and E3d have shapes different from the side surfaces E3a and E3b. Specifically, the side surfaces E3c and E3d are planes parallel to the YZ plane defined by the second direction Y and the third direction Z.

[0144] like Fig.13 As shown, the second cover part CM2 has side surfaces E4c and E4d. The side surfaces E4c and E4d have shapes different from the side surfaces E4a and E4b. Specifically, the side surfaces E4c and E4d are planes parallel to the YZ plane.

[0145] In the configuration of this embodiment, the same effect as that of the first embodiment can be obtained. In this embodiment, the side surfaces E3c, E3d, E4c, and E4d are planes. Thus, light propagating inside the first cover part CM1 and the second cover part CM2 is not easily leaked to the outside from the side surfaces E3c, E3d, E4c, and E4d. Thus, the utilization efficiency of light in the display device DSP can be improved.

[0146] [Third Embodiment]

[0147] Here, the differences from the above-mentioned embodiments are mainly mentioned, but the same structure as that of the above-mentioned embodiments can be applied to each part of the display device DSP of this embodiment.

[0148] Fig.14 as well as Fig.15 FIG. 1 is a schematic cross-sectional view of the display device DSP of this embodiment. Fig.14 The cross section of the display device DSP is observed along the first direction X. Fig.15The cross section of the display device DSP is viewed along the second direction Y. In the present embodiment, the side surfaces E3c and E3d of the first cover member CM1 and the side surfaces E4a, E4b, E4c, and E4d of the second cover member CM2 are different from those in the first embodiment.

[0149] like Fig.15 As shown, the first cover part CM1 has side surfaces E3c and E3d. The side surfaces E3c and E3d are planes parallel to the YZ plane. Fig.14 as well as Fig.15 As shown, the second cover part CM2 has side surfaces E4a, E4b, E4c, and E4d.

[0150] The side surfaces E4a and E4b are planes parallel to the XZ plane, and the side surfaces E4c and E4d are planes parallel to the YZ plane. In the configuration of this embodiment, the same effects as those of the above-described embodiments can be obtained.

[0151] [Fourth Embodiment]

[0152] Here, the differences from the above-mentioned embodiments are mainly mentioned, but the same structure as that of the above-mentioned embodiments can be applied to each part of the display device DSP of this embodiment.

[0153] Fig.16 FIG. 1 is a schematic cross-sectional view of the display device DSP of this embodiment. Fig.16 , a cross section of the display device DSP is observed along the first direction X. In this embodiment, the side surface E4a of the second cover part CM2 is different from that in the second embodiment. The side surfaces E3c and E3d of the first cover part CM1 and the side surfaces E4c and E4d of the second cover part CM2 have the same Fig.13 The examples shown are of the same construction.

[0154] like Fig.16 As shown, the second cover part CM2 has a side surface E4a. The side surface E4a is a plane parallel to the XZ plane. Although not shown, the side surfaces E3c, E3d, and the side surfaces E4c, E4d are planes parallel to the YZ plane.

[0155] In the configuration of this embodiment, the same effects as those of the above-mentioned embodiments can be obtained. In this embodiment, light is not easily leaked from the side surfaces E3c, E3d, E4c, and E4d, and the liquid crystal layer LC is easily incident with light on the light-reflecting side, thereby improving the light utilization efficiency.

[0156] In addition, in the second embodiment to the fourth embodiment, the use of Figures 10 to 12 The reflecting components RF1, RF2, RF3 are described.

[0157] Based on the display device described above as the embodiment of the present invention, any display device implemented by appropriately designing and modifying by a person skilled in the art also belongs to the scope of the present invention as long as it includes the gist of the present invention.

[0158] Within the scope of the concept of the present invention, those skilled in the art can think of various variations, and these variations should also be understood to belong to the scope of the present invention. For example, those skilled in the art appropriately add, delete, or design changes the components of the above-mentioned embodiments, or add, omit, or change the conditions of the processes, as long as they have the gist of the present invention, are included in the scope of the present invention.

[0159] Furthermore, other effects brought about by the methods described in the above-mentioned embodiments, which are obvious from the description of this specification or which can be appropriately imagined by a person skilled in the art, should of course be understood to be brought about by the present invention.

Claims

1. A display device, characterized in that: have: An array substrate; an opposing substrate, opposite to the array substrate; A liquid crystal layer, disposed between the array substrate and the counter substrate; a transparent first cover member having a first main surface opposite to the counter substrate, a second main surface opposite to the first main surface, and a first side surface extending along a first direction; as well as a light source, irradiating light toward the first side surface along a second direction intersecting the first direction, When viewed along the first direction, the first side surface is a curved surface that connects the first main surface and the second main surface and protrudes toward the light source.

2. The display device according to claim 1, wherein: The first cover component further has a second side surface extending along the first direction and arranged side by side with the first side surface in the second direction. When viewed along the first direction, the second side surface is a convex curved surface connecting the first main surface and the second main surface.

3. The display device according to claim 2, wherein: A transparent second cover component is further provided, wherein the second cover component has a third main surface opposite to the array substrate, a fourth main surface opposite to the third main surface, and a third side surface extending along the first direction. When viewed along the first direction, the third side surface is a curved surface that connects the third main surface and the fourth main surface and convexes toward the second direction.

4. The display device according to claim 3, characterized in that The second cover component further has a fourth side surface extending along the first direction and arranged side by side with the third side surface in the second direction. When viewed along the first direction, the fourth side surface is a curved surface that connects the third main surface and the fourth main surface and convexes in a direction opposite to the second direction.

5. The display device according to claim 3, characterized in that The second cover component further includes a fourth side surface extending along the first direction and arranged parallel to the third side surface in the second direction and being a plane.

6. The display device according to claim 2, wherein: The first cover component further includes a fifth side surface extending along the second direction, and a sixth side surface extending along the second direction and arranged parallel to the fifth side surface in the first direction. When viewed along the second direction, the fifth side surface and the sixth side surface are convex curved surfaces connecting the first main surface and the second main surface.

7. The display device according to claim 2, wherein: The first cover component further includes a fifth side surface extending along the second direction, and a sixth side surface extending along the second direction and arranged parallel to the fifth side surface in the first direction. The fifth side surface and the sixth side surface are planes.

8. The display device according to claim 3 or 4, characterized in that: The second cover component further includes a seventh side surface extending along the second direction, and an eighth side surface extending along the second direction and arranged parallel to the seventh side surface in the first direction. The seventh side surface and the eighth side surface are planes.

9. The display device according to claim 4, characterized in that: The second cover component further includes a seventh side surface extending along the second direction, and an eighth side surface extending along the second direction and arranged parallel to the seventh side surface in the first direction. When viewed along the second direction, the seventh side surface and the eighth side surface are convex curved surfaces connecting the third main surface and the fourth main surface.

10. The display device according to claim 1, wherein: The first side surface has a radius of curvature of not less than 2.0 mm and not more than 2.5 mm.

11. The display device according to claim 10, wherein: The first cover member has a thickness that is at least twice as great as a thickness of the array substrate.

12. The display device according to claim 1, wherein: The first side surface is formed as a mirror surface.

13. The display device according to claim 1, wherein: The first side surface is formed as a rough surface.

14. The display device according to claim 2, wherein: The first cover component further includes a fifth side surface extending along the second direction, and a sixth side surface extending along the second direction and arranged parallel to the fifth side surface in the first direction. The first side surface and the second side surface are formed as mirror surfaces, The fifth side surface and the sixth side surface are formed as rough surfaces.

15. The display device according to claim 1, wherein: It also has a reflective component. The first cover component further has a second side surface extending along the first direction and arranged side by side with the first side surface in the second direction. The reflective component is disposed on the second side surface.

16. The display device according to claim 15, characterized in that The second side surface has a portion that is located on the second main surface side in the second direction and does not overlap with the reflecting member.

17. The display device according to claim 1, wherein: Also available: a transparent second cover member; and Reflective components, The first cover component further has a second side surface extending along the first direction and arranged side by side with the first side surface in the second direction. The second cover component has a third main surface opposite to the array substrate, a fourth main surface opposite to the third main surface, and a third side surface located below the first side surface and extending along the first direction. The reflective component is disposed on the second side surface and the third side surface.

18. The display device according to claim 1, wherein: The liquid crystal layer is a polymer dispersed liquid crystal layer that can switch between a state of transmitting incident light and a state of scattering incident light according to an applied voltage.

19. The display device according to claim 1, wherein: The invention further includes a light guide disposed between the first side surface and the light source.

20. The display device according to claim 19, wherein: The array substrate has a mounting area formed in a portion protruding in a direction opposite to the second direction relative to the counter substrate. The light guide overlaps the mounting area.

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