Indication device

Abstract

To provide a display device that can suppress a decline in display quality. [Solution] A display device according to one embodiment comprises a display panel having a display area including a plurality of pixels, a light guide plate superimposed on the display panel, and a plurality of light-emitting elements that irradiate the light guide plate with light. The light guide plate has a first portion that overlaps the display area and a second portion connected to the first portion. A portion of the plurality of pixels is arranged in a matrix in a first and second direction which are orthogonal to each other. The width of the first portion in the first direction is greater than the width of the second portion in the first direction, and the second portion has, in a plan view, a first side surface that extends in a direction different from the first and second directions and a second side surface that extends in a direction different from the first side surface, and the plurality of light-emitting elements are arranged along the first and second side surfaces.

Description

Technical Field

[0001] Embodiments of the present invention relate to a display device.

Background Art

[0002] In recent years, display devices having a display panel with a polymer dispersed liquid crystal layer (PDLC), a light source, etc. have been proposed. The polymer dispersed liquid crystal layer can switch between a scattering state that scatters light and a transparent state that transmits light.

[0003] The display device can display an image in the scattering state. When the display panel is switched to the transparent state, the user can view the background through the display panel.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] One object of the present invention is to provide a display device capable of suppressing a decrease in display quality.

Means for Solving the Problems

[0006] A display device according to one embodiment has a liquid crystal layer containing polymer-dispersed liquid crystal, and is capable of switching between a state in which light incident on the liquid crystal layer is transmitted and a state in which light is scattered, depending on the applied voltage. The display device comprises a display panel having a display area including a plurality of pixels, a light guide plate superimposed on the display panel, and a plurality of light-emitting elements that irradiate the light guide plate with light. The light guide plate has a first portion that overlaps the display area and a second portion connected to the first portion. A portion of the plurality of pixels is arranged in a matrix in a first and second direction which are orthogonal to each other. The width of the first portion in the first direction is greater than the width of the second portion in the first direction, and the second portion has, in a plan view, a first side surface extending in a direction different from the first and second directions and a second side surface extending in a direction different from the first side surface, and the plurality of light-emitting elements are arranged along the first and second side surfaces.

[0007] A display device according to one embodiment comprises a display panel having a display area including a plurality of pixels, a light-transmitting substrate superimposed on the display panel and having a main surface and a side surface intersecting the main surface, and a plurality of light-emitting elements arranged along a part of the side surface. The substrate has a non-overlapping region that does not overlap with the display panel. The part of the side surface includes a first side surface and a second side surface located in the non-overlapping region. In a plan view, the first extension direction in which the first side surface extends is different from the second extension direction in which the second side surface extends. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 shows an example of the configuration of a display device according to the first embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view of the display panel shown in Figure 1. [Figure 3] Figure 3 is a schematic plan view of the display device according to the first embodiment. [Figure 4] Figure 4 is a schematic side view of the display device according to the first embodiment. [Figure 5]Figure 5 is a schematic plan view of a display device according to a comparative example. [Figure 6] Figure 6 is a schematic side view showing another example of the display device according to the first embodiment. [Figure 7] Figure 7 is a schematic plan view of the display device according to the second embodiment. [Figure 8] Figure 8 is a schematic plan view showing another example of the display device according to the second embodiment. [Figure 9] Figure 9 is a schematic plan view of the display device according to the third embodiment. [Figure 10] Figure 10 is a schematic plan view of the display device according to the fourth embodiment. [Figure 11] Figure 11 is a schematic plan view of the display device according to the fifth embodiment. [Modes for carrying out the invention]

[0009] The embodiments will be described below with reference to the drawings. It should be noted that the disclosure is merely illustrative, and any modifications that a person skilled in the art could easily conceive of while maintaining the spirit of the invention are naturally included within the scope of the present invention.

[0010] Furthermore, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. In addition, in this specification and each drawing, the same reference numerals are used for components that perform the same or similar functions as those described above with respect to previously shown drawings, and redundant detailed explanations may be omitted as appropriate.

[0011] Furthermore, the drawings will include mutually orthogonal X, Y, and Z axes as needed to facilitate understanding. The direction along the X axis will be referred to as the first direction X, the direction along the Y axis as the second direction Y, and the direction along the Z axis as the third direction Z. Viewing the various elements parallel to the third direction Z is called a plan view.

[0012] In each embodiment, as an example of a display device, a highly transparent liquid crystal display device (so-called transparent display device) applying polymer-dispersed liquid crystal is disclosed. However, the configurations disclosed in each embodiment are also applicable to other types of display devices.

[0013] [First Embodiment] FIG. 1 is a diagram showing a configuration example of a display device DSP according to this embodiment. The display device DSP includes a display panel PNL. The display panel PNL includes a first substrate SUB1 and a second substrate SUB2 stacked in the third direction Z. The first substrate SUB1 and the second substrate SUB2 are formed in a flat plate shape parallel to the X-Y plane defined by the X-axis and the Y-axis.

[0014] In the example shown in FIG. 1, the first substrate SUB1 and the second substrate SUB2 have a shape that is long in the first direction X in plan view. Specifically, the first substrate SUB1 and the second substrate SUB2 have a shape in which one end on the short axis side of an ellipse is missing.

[0015] Note that the shapes of the first substrate SUB1 and the second substrate SUB2 are not limited to this example, and the first substrate SUB1 and the second substrate SUB2 may have an oval shape, a rectangular shape, or other shapes. From another perspective, the first substrate SUB1 and the second substrate SUB2 have a symmetric shape having a symmetry axis extending in the second direction Y.

[0016] The first substrate SUB1 has a side surface E1 and a side surface E2. The side surface E1 has a linear shape extending in the first direction X. The side surface E2 is connected to both ends of the side surface E1. The side surface E2 has a curved shape. Specifically, the side surface E2 is formed so as to spread in the first direction X and the opposite direction of the first direction X more than the side surface E1.

[0017] The second substrate SUB2 has a side surface E3 and a side surface E4. The side surface E3 has a linear shape extending in the first direction. The side surface E4 has the same shape as the side surface E3. The display panel PNL has a curved portion in plan view. The side surface E4 is connected to both ends of the side surface E3. The side surface E4 overlaps the side surface E2 in the third direction Z.

[0018] The width of the first substrate SUB1 in the second direction Y is larger than the width of the second substrate SUB2 in the second direction Y. The first substrate SUB1 has a mounting area MA formed in a portion protruding in the direction opposite to the second direction Y from the second substrate SUB2.

[0019] The mounting area MA corresponds to the area of the first substrate SUB1 that does not overlap the second substrate SUB2. In other words, the mounting area MA corresponds to the area between the side surface E1 and the side surface E3 in the second direction Y. An integrated circuit or a flexible circuit board (not shown) is mounted in the mounting area MA.

[0020] The display panel PNL has a display area DA for displaying an image and a peripheral area SA surrounding the display area DA. Both the display area DA and the peripheral area SA are formed in the portion where the first substrate SUB1 and the second substrate SUB2 overlap. The display area DA includes a plurality of pixels PX arranged in a matrix in the first direction X and the second direction Y.

[0021] The display panel PNL further includes a liquid crystal layer LC sealed between the first substrate SUB1 and the second substrate SUB2. As schematically shown in an enlarged view below FIG. 1, the liquid crystal layer LC is composed of a polymer dispersed liquid crystal containing a polymer 31 and liquid crystal molecules 32.

[0022] In one example, the polymer 31 is a liquid crystalline polymer. The polymer 31 is formed in a streak shape extending along the first direction X and is arranged at intervals in the second direction Y. The liquid crystal molecules 32 are dispersed in the gaps of the polymer 31 and are oriented such that their long axes are along the first direction X.

[0023] Each of the polymer 31 and the liquid crystal molecules 32 possesses optical anisotropy or refractive index anisotropy. The responsiveness of polymer 31 to an electric field is lower than that of liquid crystal molecules 32. In one example, the orientation direction of polymer 31 hardly changes regardless of the presence or absence of an electric field. In contrast, the orientation direction of liquid crystal molecules 32 changes in response to the voltage applied to the liquid crystal layer LC.

[0024] 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 with almost no scattering (transparent state).

[0025] 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 the light incident on the liquid crystal layer LC is scattered within the liquid crystal layer LC (scattering state). In this way, the display device DSP can switch between a transparent state and a scattering state depending on the applied voltage.

[0026] As shown in the enlarged view above Figure 1, the display area DA contains multiple scan lines G and multiple signal lines S. The multiple scan lines G extend in the first direction X and are aligned in the second direction Y. The multiple signal lines S extend in the second direction Y and are aligned in the first direction X. The multiple signal lines S intersect with the multiple scan lines G.

[0027] Each pixel PX comprises a switching element SW, a pixel electrode PE, a common electrode CE, and a capacitor CS. The switching element SW is composed of, for example, a thin-film transistor (TFT) and is electrically connected to the scan line G and the signal line S. The pixel electrode PE is electrically connected to the switching element SW.

[0028] The liquid crystal layer LC (particularly the liquid crystal molecules 32) is driven by the electric field generated between the pixel electrode PE and the common electrode CE. A capacitance CS is formed, for example, between an electrode at the same potential as the common electrode CE and an electrode at the same potential as the pixel electrode PE.

[0029] Figure 2 is a schematic cross-sectional view of the display panel PNL shown in Figure 1. The first substrate SUB1 comprises a first transparent substrate 10, insulating films 11 and 12, a capacitive electrode 13, a switching element SW, a pixel electrode PE, and an alignment film AL1.

[0030] Although not shown in the diagram, the first substrate SUB1 further includes the scan lines G and signal lines S shown in Figure 1. The switching element SW is located on the main surface 10B of the first transparent substrate 10. The main surface 10B is the surface facing the second substrate SUB2. The insulating film 11 covers the switching element SW. The capacitive electrode 13 is located between the insulating film 11 and the insulating film 12.

[0031] In the illustrated example, the insulating film 11 and the capacitive electrode 13 are arranged across the entire surface of each pixel PX, but the example is not limited to this. The insulating film 11 only needs to be arranged to cover at least the switching element SW, the scan line G, and the signal line S.

[0032] The capacitive electrodes 13 may be formed in a grid pattern along the scan lines G and signal lines S. Pixel electrodes PE are arranged on the insulating film 12 for each pixel PX. The pixel electrodes PE are electrically connected to the switching element SW through the opening OP of the capacitive electrodes 13. The pixel electrodes PE overlap the capacitive electrodes 13 with the insulating film 12 in between, forming the capacitance CS of the pixel PX. The alignment film AL1 covers the pixel electrodes PE.

[0033] The second substrate SUB2 comprises a second transparent substrate 20, a light-shielding layer BM, a common electrode CE, and an alignment film AL2. The second transparent substrate 20 faces the first transparent substrate 10 in the third direction Z.

[0034] The light-shielding layer BM and the common electrode CE are located on the main surface 20A of the second transparent substrate 20. The main surface 20A is the surface facing the first transparent substrate 10. The light-shielding layer BM is located, for example, directly above the switching element SW and directly above the scan line G and signal line S (not shown).

[0035] The common electrode CE faces the pixel electrode PE in the third direction Z, with the liquid crystal layer LC in between. The common electrode CE is arranged across multiple pixels PX and directly covers the light-shielding layer BM. The common electrode CE is electrically connected to the capacitive electrode 13 and is at the same potential as the capacitive electrode 13. The alignment film AL2 covers the common electrode CE.

[0036] The liquid crystal layer LC is located between the first transparent substrate 10 and the second transparent substrate 20 and is in contact with the alignment films AL1 and AL2. In the first substrate SUB1, the insulating film 11, insulating film 12, capacitive electrode 13, switching element SW, pixel electrode PE, alignment film AL1, scan line G, and signal line S are located between the first transparent substrate 10 and the liquid crystal layer LC. In the second substrate SUB2, the light-shielding layer BM, common electrode CE, and alignment film AL2 are located between the second transparent substrate 20 and the liquid crystal layer LC.

[0037] The first transparent substrate 10 and the second transparent substrate 20 are insulating substrates such as glass substrates and plastic substrates. The insulating film 11 is formed from a transparent insulating material such as silicon oxide, silicon nitride, silicon oxynitride, or acrylic resin.

[0038] In one example, the insulating film 11 includes an inorganic insulating film and an organic insulating film. The insulating film 12 is an inorganic insulating film such as silicon nitride. The capacitive electrode 13, the pixel electrode PE, and the common electrode CE are transparent electrodes formed from transparent conductive materials such as indium tin oxide (ITO) and indium zinc oxide (IZO). The light-shielding layer BM is, for example, a conductive layer with lower resistance than the common electrode CE.

[0039] In one example, the light-shielding layer BM is formed from an opaque metallic material such as molybdenum, aluminum, tungsten, titanium, or silver. The alignment films AL1 and AL2 are horizontal alignment films having an alignment restricting force substantially parallel to the XY plane. In one example, the alignment films AL1 and AL2 are oriented along the first direction X. The orientation treatment may be a rubbing treatment or a photo-alignment treatment.

[0040] Figure 3 is a schematic plan view of the display device DSP according to this embodiment. Figure 4 is a schematic side view of the display device DSP according to this embodiment. In Figure 4, the display device DSP is viewed in the first direction X.

[0041] As shown in Figures 3 and 4, the display device DSP further includes a light guide plate 30 that is translucent. The light guide plate 30 is a transparent substrate, for example, a glass substrate, but it may also be an insulating substrate such as a plastic substrate.

[0042] In the example shown in Figure 4, the thickness of the light guide plate 30 is greater than the thickness of the first substrate SUB1 and the second substrate SUB2. Here, thickness refers to the distance along the third direction Z. In one example, the light guide plate 30 has a thickness of more than twice that of the first substrate SUB1 and the second substrate SUB2.

[0043] The size of the light guide plate 30 in a plan view is larger than the size of the display panel PNL in a plan view. The light guide plate 30 has a first portion 301 that overlaps the display panel PNL and a second portion 302 that is connected to the first portion 301. The first portion 301 and the second portion 302 are formed integrally, for example. However, the first portion 301 and the second portion 302 may be formed from separate components.

[0044] The first portion 301 includes a portion that overlaps with the display area DA in a plan view. In this embodiment, the size of the display panel PNL is equivalent to the size of the first portion 301 in a plan view. In this embodiment, the second portion 302 corresponds to a portion that does not overlap with the display panel PNL (non-overlapping area). In Figure 3, the second portion 302 is marked with a dot.

[0045] The second part 302 has a roughly triangular shape in plan view. The width of the second part 302 in the first direction X decreases at a constant rate as it moves away from the first part 301 (along the direction opposite to the second direction Y).

[0046] As shown in Figures 3 and 4, the light guide plate 30 has a main surface 30A, a main surface 30B opposite to the main surface 30A, and side surfaces 30C, 30D, and 30E that connect the main surface 30A and the main surface 30B. The side surfaces 30C, 30D, and 30E are surfaces that intersect the main surfaces 30A and 30B.

[0047] In this embodiment, side surface 30C is an example of a first side surface, and side surface 30D is an example of a second side surface. The main surfaces 30A and 30B are planes parallel to the XY plane. Main surface 30A faces the second substrate SUB2. The light guide plate 30 is bonded to, for example, the second transparent substrate 20 by an adhesive layer (not shown).

[0048] Sides 30C and 30D are included in the second part 302, and side 30E is included in the first part 301. In a plan view, sides 30C and 30D extend in directions different from the first direction X and the second direction Y.

[0049] Sides 30C and 30D extend in different directions. Here, the direction that intersects the second direction Y at an acute angle counterclockwise is defined as direction D1, and the direction that intersects the second direction Y at an acute angle clockwise is defined as direction D2. In this embodiment, direction D1 is an example of a first extension direction, and direction D2 is an example of a second extension direction.

[0050] Note that the angle between the second direction Y and direction D1, and the angle between the second direction Y and direction D2 are, for example, the same, but the angle between the second direction Y and direction D1 may be different from the angle between the second direction Y and direction D2.

[0051] Side 30C extends along direction D1, and side 30D extends along direction D2. For example, side 30C coincides with a tangent passing through one end of side 30E, and side 30D coincides with a tangent passing through the other end of side 30E. The second portion 302 is formed up to the point where these tangents intersect in the example shown in Figure 3. That is, side 30C is formed to intersect side 30D.

[0052] The length of side 30C is, for example, equivalent to the length of side 30D. In the example shown in Figure 3, both sides 30C and 30D extend in a straight line. One end of side 30C is connected to one end of side 30D. The angle θ1 between side 30C and side 30D is, for example, 90 degrees, but is not limited to this example.

[0053] Side surface 30E is formed in a curved shape and connects sides 30C and 30D. In the example shown in Figure 4, side surface 30E overlaps with side surface E2 of the first substrate SUB1 and side surface E4 of the second substrate SUB2.

[0054] The width W1 of the first part 301 in the first direction X is greater than the width W2 of the second part 302 in the first direction X. Width W1 is the maximum width of the first part 301 in the first direction X, and width W2 is the maximum width of the second part 302 in the first direction X. Also, width W1 corresponds to the width of the display panel PNL in the first direction X.

[0055] The first part 301 has regions A1 and A2 (outer regions) located outside the second part 302 in both the first direction X and the direction opposite to the first direction X. In Figure 3, regions A1 and A2 are shaded.

[0056] The widths of regions A1 and A2 correspond to the difference between widths W1 and W2. Regions A1 and A2 overlap with display region DA. Display region DA has a width greater than the width W2 in the first direction X of the second portion 302.

[0057] The display device DSP further includes light source units LU1 and LU2. Light source unit LU1 is positioned along side 30C (direction D1), and light source unit LU2 is positioned along side 30D (direction D2).

[0058] Light source unit LU1 has multiple light-emitting elements LS arranged along side 30C. Light source unit LU2 has multiple light-emitting elements LS arranged along side 30D. The multiple light-emitting elements LS arranged along side 30C (first side) and side 30D (second side) are an example of the first group of light-emitting elements. In other respects, the multiple light-emitting elements LS do not face each other on sides other than sides 30C and 30D.

[0059] Multiple light-emitting elements LS irradiate light toward sides 30C and 30D. In the example shown in Figure 3, the emission surface of the light-emitting elements LS of light source unit LU1 faces direction D2, and the emission surface of the light-emitting elements LS of light source unit LU2 faces direction D1.

[0060] From another perspective, at least one of the light-emitting elements LS of light source unit LU1 has its emission surface facing region A2, and at least one of the light-emitting elements LS of light source unit LU2 has its emission surface facing region A1.

[0061] In other words, region A2 is located in the direction normal to at least one emission surface of the light-emitting element LS of light source unit LU1, and region A1 is located in the direction normal to at least one emission surface of the light-emitting element LS of light source unit LU2.

[0062] For example, a plurality of light-emitting elements LS may include a light-emitting element that emits red light, a light-emitting element that emits green light, and a light-emitting element that emits blue light. These light-emitting elements may be arranged in directions D1 and D2, or they may be stacked in a third direction Z.

[0063] An LED (Light Emitting Diode) can be used as the light-emitting element LS. Furthermore, a light guide such as a prism lens may be placed between the light source unit LU1 and the side surface 30C, and between the light source unit LU2 and the side surface 30D.

[0064] Here, we will explain the path of the light L1 emitted by the light-emitting element LS of the light source unit LU1. The light L1 emitted from the light-emitting element LS is incident on the side surface 30C. This light travels from the second part 302 to the first part 301, undergoing repeated total internal reflection between the main surface 30B and the main surface 30A of the light guide plate 30.

[0065] Of the light that reaches the first section 301, the light that propagates to the main surface 30A propagates to the pixels PX in the transparent and scattered states as follows. First, in the vicinity of the transparent pixels PX, the light is hardly scattered by the liquid crystal layer LC. Therefore, the light hardly leaks out of the light guide plate 30 and the first transparent substrate 10.

[0066] On the other hand, near pixels PX in a scattered state, light is scattered by the liquid crystal layer LC. This scattered light is emitted from the light guide plate 30 and the first transparent substrate 10 and is visible to the user as a displayed image. By gradually defining the voltage applied to the pixel electrode PE within a predetermined range, it is also possible to achieve gradation in the degree of scattering (brightness). Similarly, the light L2 emitted by the light-emitting element LS of the light source unit LU2 also travels inside the light guide plate 30 and the display panel PNL.

[0067] Furthermore, in the vicinity of the transparent pixels PX, ambient light incident on the light guide plate 30 and the first transparent substrate 10 is transmitted through the liquid crystal layer LC with almost no scattering. That is, when viewing the display panel PNL from the light guide plate 30 side, the background on the first transparent substrate 10 side is visible, and when viewing the display panel PNL from the first transparent substrate 10 side, the background on the light guide plate 30 side is visible.

[0068] Figure 5 is a schematic plan view of a comparative example display device DSP10. The display device DSP10 is equipped with a display panel PNL, similar to this embodiment. The light guide plate 40 of the display device DSP10 has the same size as the display panel PNL in a plan view. In other words, the light guide plate 40 corresponds to the first part 301 of the light guide plate 30 in this embodiment.

[0069] The light guide plate 40 has sides 40A and 40B. Side 40A has a linear shape extending in the first direction X. Side 40A overlaps with side E1 of the first substrate SUB1 in the third direction Z. Side 40B is connected to both ends of side 40A. Side 40B overlaps with side E2 of the first substrate SUB1 and side E4 of the second substrate SUB2.

[0070] The display device DSP10 further comprises a light source unit LU3. The light source unit LU3 is arranged along the side 40A (first direction X). The light source unit LU3 comprises a plurality of light-emitting elements LS arranged along the side 40A.

[0071] The light-emitting element LS of the light source unit LU3 is oriented in the second direction Y. The light-emitting element LS of the light source unit LU3 emits light toward the side surface 40A. The light emitted from the light source unit LU3 travels through the inside of the light guide plate 40 in the second direction Y.

[0072] The width W1 of the light guide plate 40 in the first direction is greater than the width W10 of the side surface 40A in the first direction X. Therefore, the light guide plate 40, as in this embodiment, has regions A1 and A2 located outside the side surface 40A in the first direction X and the direction opposite to the first direction X.

[0073] Areas A1 and A2 are regions where light from the light source unit LU3 does not easily penetrate. Therefore, brightness tends to decrease in areas A1 and A2 compared to other areas. This can lead to a decrease in display quality.

[0074] In this embodiment, as shown in Figure 3, the light L1 emitted by the light-emitting element LS of the light source unit LU1 easily enters region A2, and the light L2 emitted by the light-emitting element LS of the light source unit LU2 easily enters region A1.

[0075] Specifically, the light guide plate 30 has sides 30C and 30D in the second portion 302. Sides 30C and 30D extend in directions different from the first direction X and the second direction Y. The light-emitting elements LS of the light source units LU1 and LU2 irradiate light toward sides 30C and 30D.

[0076] Light L1 emitted by the light-emitting element LS of the light source unit LU1 can enter region A2 of the first part 301 from the side surface 30C via the second part 302. Light L2 emitted by the light-emitting element LS of the light source unit LU2 can enter region A1 of the first part 301 from the side surface 30D via the second part 302. In other words, the second part 302 functions as a light guide layer for allowing light to enter regions A1 and A2.

[0077] Thus, since light from light source units LU1 and LU2 can enter regions A1 and A2, the brightness in regions A1 and A2 is less likely to decrease. This improves the uniformity of brightness in the first section 301.

[0078] Even when areas A1 and A2 overlap with display area DA, the uniformity of the brightness of display area DA can be improved. As a result, a decrease in display quality in the display device DSP can be suppressed.

[0079] Note that the shape of the display panel PNL is not limited to the examples described above. Figure 6 is a schematic side view showing another example of the display device DSP according to this embodiment. The display panel PNL may have the same size as the light guide plate 30, as shown in Figure 6. In this case, the second portion 302 of the light guide plate 30 overlaps with the display panel PNL. This makes it possible to increase the intensity in the third direction Z in the display device DSP.

[0080] In this embodiment, the first portion 301 had both regions A1 and A2, but the first portion 301 only needs to have a region (outer region) that is located outside the second portion 302 in at least one of the first direction X and the direction opposite to the first direction X.

[0081] In this embodiment, an example is disclosed in which the width of the display area DA in the first direction X is greater than the width W2 of the second portion 302 in the first direction X. However, the width of the display area DA in the first direction X may be smaller than the width W2 of the second portion 302 in the first direction X.

[0082] With a display device DSP configured as described above, a decrease in display quality can be suppressed.

[0083] Next, other embodiments will be described. In the following embodiments, the parts that are not specifically mentioned can be the same as those in the first embodiment.

[0084] [Second Embodiment] Figure 7 is a schematic plan view of the display device DSP according to this embodiment. In this embodiment, the shape of the second portion 302 of the light guide plate 30 differs from that of the first embodiment. Specifically, the second portion 302 has a substantially trapezoidal shape.

[0085] Side 30C is spaced apart from side 30D. The light guide plate 30 further has side 30F in the second portion 302. Side 30F is located between side 30C and side 30D. In this embodiment, side 30C is an example of a first side, side 30D is an example of a second side, and side 30F is an example of a third side. Side 30F connects side 30C and side 30D. In the example shown in Figure 7, side 30F extends along the first direction X.

[0086] As shown in Figure 7, the angle between side 30F and side 30C is defined as angle θ2, and the angle between side 30F and side 30D is defined as angle θ3. In this embodiment, angle θ2 is equivalent to angle θ3. Also, angles θ2 and θ3 are greater than 90 degrees and less than 180 degrees. In other words, angles θ2 and θ3 are obtuse angles.

[0087] The display device DSP further comprises a light source unit LU4. The light source unit LU4 is arranged along the side 30F (first direction X). The light source unit LU4 comprises a plurality of light-emitting elements LS arranged along the side 30F. The plurality of light-emitting elements LS arranged along the side 30F (third side) is an example of a second group of light-emitting elements. The plurality of light-emitting elements LS emit light toward the side 30F. In the example shown in Figure 7, the emission surface of the light-emitting elements LS of the light source unit LU4 faces the second direction Y.

[0088] In this embodiment, the same effects as in the first embodiment can be obtained. In this embodiment, a light source unit LU4 is provided that irradiates light in the second direction Y. As a result, the amount of light traveling in directions other than D1 and D2 (the second direction Y) increases, and the brightness of the area on the reverse side of the light can be further improved. As a result, the deterioration of display quality can be further suppressed.

[0089] Note that the difference between the width W1 of the first part 301 in the first direction X and the width W2 of the second part 302 in the first direction X may be greater than that shown in the example in Figure 7. Figure 8 is a schematic plan view showing another example of the display device DSP according to this embodiment.

[0090] In this embodiment as well, at least one of the light-emitting elements LS of the light source unit LU1 has its emission surface facing region A2, and at least one of the light-emitting elements LS of the light source unit LU2 has its emission surface facing region A1. As a result, even with the shape of the light guide plate 30 shown in Figure 8, light can be directed into regions A1 and A2.

[0091] [Third Embodiment] Figure 9 is a schematic plan view of the display device DSP according to this embodiment. In this embodiment, the shapes of the display panel PNL and the light guide plate 30 differ from those of the first embodiment. In this embodiment, the display panel PNL has a circular shape. Similarly, the display area DA also has a circular shape.

[0092] The light guide plate 30 overlaps the entire display panel PNL. The light guide plate 30 has a first portion 301 that overlaps the display panel PNL and a second portion 302 that is connected to the first portion 301. The width W1 of the first portion 301 in a first direction X is greater than the width W2 of the second portion 302 in a first direction X.

[0093] The light guide plate 30 has sides 30G, 30H, and 30I. In this embodiment, side 30G is an example of a first side, and side 30H is an example of a second side. Sides 30G and 30H are included in the second part 302, and side 30I is included in the first part 301. Side 30G extends along direction D1, and side 30H extends along direction D2. The length of side 30G is, for example, equivalent to the length of side 30H.

[0094] In the example shown in Figure 9, both sides 30G and 30H extend in a straight line. Side 30I is formed in an arc shape and connects sides 30G and 30H. Side 30I is formed to extend further than sides 30G and 30H in the first direction X and the direction opposite to the first direction X.

[0095] The display device DSP further includes light source units LU5 and LU6. Light source unit LU5 is positioned along side 30G, and light source unit LU6 is positioned along side 30H.

[0096] Light source unit LU5 has multiple light-emitting elements LS arranged along side 30G. Light source unit LU6 has multiple light-emitting elements LS arranged along side 30H. The multiple light-emitting elements LS emit light toward sides 30G and 30H. The multiple light-emitting elements LS arranged along side 30G (first side) and side 30H (second side) are an example of the first group of light-emitting elements.

[0097] The first part 301 has regions A3 and A4 (outer regions) located outside the second part 302 in both the first direction X and the direction opposite to the first direction X. In Figure 9, regions A3 and A4 are shaded. Regions A3 and A4 overlap, for example, with the display region DA.

[0098] At least one of the light-emitting elements LS of light source unit LU5 has its emission surface facing region A4, and at least one of the light-emitting elements LS of light source unit LU6 has its emission surface facing region A3.

[0099] In this embodiment as well, the same effects as in the first embodiment can be obtained. In this embodiment, the light emitted by the light-emitting element LS of the light source unit LU5 enters region A4, and the light emitted by the light-emitting element LS of the light source unit LU6 enters region A3. As a result, the brightness in regions A3 and A4 is less likely to decrease. Consequently, the uniformity of brightness in the first portion 301 can be improved.

[0100] [Fourth Embodiment] Figure 10 is a schematic plan view of the display device DSP according to this embodiment. In this embodiment, the shape of the second portion 302 of the light guide plate 30 differs from that of the third embodiment.

[0101] The light guide plate 30 further has a side surface 30J in the second portion 302. In this embodiment, side surface 30G is an example of a first side surface, side surface 30H is an example of a second side surface, and side surface 30J is an example of a third side surface. Side surface 30J connects side surface 30G and side surface 30H. In the example shown in Figure 10, side surface 30J extends along the first direction X.

[0102] As shown in Figure 10, the angle between side 30G and side 30J is defined as angle θ4, and the angle between side 30H and side 30J is defined as angle θ5. In this embodiment, angle θ4 is equivalent to angle θ5. Also, angles θ4 and θ5 are greater than 90 degrees and less than 180 degrees.

[0103] The display device DSP further comprises a light source unit LU7. The light source unit LU7 is arranged along the side 30J (first direction X). The light source unit LU7 comprises multiple light-emitting elements LS arranged along the side 30J. The multiple light-emitting elements LS emit light toward the side 30J. The multiple light-emitting elements LS arranged along the side 30J (third side) is an example of a second group of light-emitting elements. In the example shown in Figure 10, the emission surface of the light-emitting elements LS of the light source unit LU7 faces the second direction Y.

[0104] In this embodiment as well, the same effects as in the third embodiment can be obtained. In this embodiment, a light source unit LU7 is provided that irradiates light in the second direction Y. As a result, the amount of light traveling in directions other than D1 and D2 (the second direction Y) increases, and the brightness of the area on the reverse side of the light can be further improved. As a result, the deterioration of display quality can be further suppressed.

[0105] [Fifth Embodiment] Figure 11 is a schematic plan view of the display device DSP according to this embodiment. In this embodiment, the shapes of the display panel PNL and the light guide plate 30 differ from those of the first embodiment. In this embodiment, the display panel PNL has an elongated shape in the first direction X when viewed from above. The display panel PNL has, for example, a non-symmetrical shape.

[0106] The light guide plate 30 overlaps the entire display panel PNL. The light guide plate 30 has a first portion 301 that overlaps the display panel PNL and a second portion 302 that is connected to the first portion 301. The width W1 of the first portion 301 in a first direction X is greater than the width W2 of the second portion 302 in a first direction X.

[0107] The light guide plate 30 has sides 30K, 30L, 30M, and 30N. In this embodiment, side 30K is an example of a first side, side 30L is an example of a second side, and side 30M is an example of a third side. Sides 30K, 30L, and 30M are included in the second part 302, and side 30N is included in the first part 301.

[0108] Side 30K extends along direction D1, side 30L extends along direction D2, and side 30M extends along the first direction X. The length of side 30K is, for example, equivalent to the length of side 30L.

[0109] In the example shown in Figure 11, both sides 30K and 30L extend in a straight line. Side 30M extends in the first direction X and connects sides 30K and 30L. Side 30N includes both a straight and a curved portion and connects sides 30K and 30L. Side 30N is formed to extend in the opposite direction to the first direction X compared to side 30K.

[0110] The display device DSP further comprises light source units LU8, LU9, and LU10. Light source unit LU8 is positioned along side 30K, light source unit LU9 is positioned along side 30L, and light source unit LU10 is positioned along side 30M.

[0111] Light source unit LU8 has multiple light-emitting elements LS arranged along side 30K. Light source unit LU9 has multiple light-emitting elements LS arranged along side 30L. Light source unit LU10 has multiple light-emitting elements LS arranged along side 30M. The multiple light-emitting elements LS emit light toward sides 30K, 30L, and 30M. The multiple light-emitting elements LS arranged along side 30K (first side) and side 30L (second side) are an example of the first group of light-emitting elements. The multiple light-emitting elements LS arranged along side 30M (third side) are an example of the second group of light-emitting elements.

[0112] The first part 301 has a region A5 (outer region) located outside the second part 302 in the direction opposite to the first direction X. In Figure 11, region A5 is shaded. Region A5 overlaps, for example, with the display region DA. At least one of the light-emitting elements LS of the light source unit LU9 has its emission surface facing region A5.

[0113] In this embodiment as well, the same effects as in the first embodiment can be obtained. In this embodiment, the light emitted by the light-emitting element LS of the light source unit LU9 enters region A5. As a result, the brightness in region A5 is less likely to decrease. Consequently, the uniformity of brightness in the first portion 301 can be improved.

[0114] All display devices that a person skilled in the art can implement by appropriately modifying the design based on the display devices described above as embodiments of the present invention also fall within the scope of the present invention insofar as they encompass the gist of the present invention. Within the scope of the idea of ​​the present invention, a person skilled in the art can conceive of various modifications, and these modifications are also understood to fall within the scope of the present invention. For example, any modifications made by a person skilled in the art to add, delete, or modify components, or to add, omit, or change the conditions of the above-described embodiments, are also included within the scope of the present invention insofar as they retain the gist of the present invention.

[0115] Furthermore, any other effects and advantages brought about by the embodiments described above that are obvious from the description herein or that can be appropriately conceived by those skilled in the art are naturally considered to be brought about by the present invention. [Explanation of Symbols]

[0116] 10...First transparent substrate, 20...Second transparent substrate, 30...Light guide plate, 30C, 30D, 30I...Side, 301...First part, 302...Second part, DA...Display area, DSP...Display device, LC...Liquid crystal layer, LS...Light-emitting element, PNL...Display panel, PX...Pixel.

Claims

1. A display device having a liquid crystal layer containing polymer-dispersed liquid crystal, which can switch between a state in which light incident on the liquid crystal layer is transmitted and a state in which light is scattered, depending on the applied voltage, A display panel having a display area containing multiple pixels, A light guide plate superimposed on the aforementioned display panel, The light guide plate is provided with a plurality of light-emitting elements that irradiate light onto it, The light guide plate has a first portion that overlaps the display area and a second portion that is connected to the first portion. Some of the aforementioned plurality of pixels are arranged in a matrix in a first and second direction which are orthogonal to each other. The width of the first portion in the first direction is greater than the width of the second portion in the first direction. The second portion has, in a plan view, a first surface extending in a direction different from the first and second directions, and a second surface extending in a direction different from the first surface. The plurality of light-emitting elements are arranged along the first side and the second side, Display device.

2. The first portion has an outer region that is located outside the second portion in at least one of the first direction and the direction opposite to the first direction. The display device according to claim 1.

3. The first portion has an outer region in both the first direction and the direction opposite to the first direction. The display device according to claim 1.

4. The outer region overlaps the display region. The display device according to claim 2 or 3.

5. The width of the second portion in the first direction decreases as it moves away from the first portion. The display device according to claim 1.

6. The second part further comprises a third side connecting the first side and the second side, The plurality of light-emitting elements include a first group of light-emitting elements arranged along the first and second sides, and a second group of light-emitting elements arranged along the third side. The display device according to claim 1.

7. The third side extends along the first direction, The display device according to claim 6.

8. The angle between the first side and the third side is equivalent to the angle between the second side and the third side. The display device according to claim 7.

9. The angle between the first side and the third side, and the angle between the second side and the third side, are greater than 90 degrees and less than 180 degrees. The display device according to claim 8.

10. The size of the display panel is equivalent to the size of the first part. The display device according to claim 1.

11. The size of the display panel is equivalent to the size of the light guide plate. The display device according to claim 1.

12. The display panel has a circular shape in plan view. The display device according to claim 1.

13. The display panel has a curved portion in a plan view. The display device according to claim 1.

14. The liquid crystal layer comprises polymers extending in the first direction and arranged at intervals in the second direction, and liquid crystal molecules disposed between the polymers. The display device according to claim 1.

15. A display panel having a display area containing multiple pixels, A substrate is superimposed on the display panel, and has a main surface and a side surface intersecting the main surface, and is translucent, The system comprises a plurality of light-emitting elements arranged along a portion of the aforementioned side surface, The substrate has a non-overlapping region that does not overlap with the display panel. The portion of the aforementioned side surface includes a first side surface and a second side surface located in the non-overlapping region, In a plan view, the first extension direction in which the first side surface extends is different from the second extension direction in which the second side surface extends. Display device.

16. The first side intersects with the second side, The display device according to claim 15.

17. The plurality of light-emitting elements are arranged along the first side and the second side, Of the aforementioned sides, the sides other than the first and second sides do not face the plurality of light-emitting elements. The display device according to claim 15.

18. The first side is spaced apart from the second side, The portion of the aforementioned side surface includes a third side surface located between the first side surface and the second side surface. The direction in which the third side surface extends is different from the first and second extension directions. The plurality of light-emitting elements are arranged along the first side, the second side, and the third side. The display device according to claim 15.

Images