Indication device

Abstract

To provide a display device or transparent display device with high display quality. [Solution] The display device comprises multiple gate lines, multiple video signal lines intersecting the gate lines, and multiple pixels. The multiple pixels are arranged in a matrix with multiple rows and multiple columns, and each pixel is electrically connected to a corresponding gate line and a corresponding video signal line. Each of the multiple gate lines has a zigzag shape. The pitch of the zigzag shape in the row direction is an integer multiple of the pitch of the video signal lines in the row direction.

Description

Technical Field

[0001] One embodiment of the present invention relates to a display device.

Background Art

[0002] In recent years, display devices that include a liquid crystal layer composed of polymer-dispersed liquid crystal in each pixel have been proposed. In such a liquid crystal layer, the transmission and scattering of light incident on the liquid crystal layer can be controlled by the voltage applied to the liquid crystal layer. By utilizing this feature, pixels that transmit light and pixels that scatter light can be created by controlling the voltage applied to the liquid crystal layer. Therefore, in a display device including polymer-dispersed liquid crystal, an image can be displayed using pixels that scatter light, and the display device can be provided with translucency by pixels that transmit light. As a result, a so-called transparent display device can be provided. For example, Patent Document 1 proposes a structure for preventing scattering of light from a light source by a gate line and selectively causing light scattering in the liquid crystal layer to prevent image quality degradation.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One embodiment of the present invention aims to provide a display device having a novel structure. Alternatively, one embodiment of the present invention aims to provide a display device with high display quality or a transparent display device.

Means for Solving the Problems

[0005] One embodiment of the present invention is a display device. The display device comprises a plurality of gate lines, a plurality of video signal lines intersecting the plurality of gate lines, and a plurality of pixels. The plurality of pixels are arranged in a matrix having a plurality of rows and a plurality of columns, and each pixel is electrically connected to a corresponding one of the plurality of gate lines and a corresponding one of the plurality of video signal lines. Each of the plurality of gate lines has a zigzag shape. The pitch in the row direction of the bending points of the zigzag shape is an integer multiple of the pitch in the row direction of the plurality of video signal lines. [Brief explanation of the drawing]

[0006] [Figure 1] A schematic unfolded perspective view of a display device according to one embodiment of the present invention. [Figure 2] A schematic end view of a display device according to one embodiment of the present invention. [Figure 3] An equivalent circuit diagram of a pixel in a display device according to one embodiment of the present invention. [Figure 4] A schematic top view of a display device according to one embodiment of the present invention. [Figure 5] A schematic top view of a display device according to one embodiment of the present invention. [Figure 6] A schematic top view of a display device according to one embodiment of the present invention. [Figure 7] A schematic top view of a display device according to one embodiment of the present invention. [Figure 8] A schematic top view of a display device according to one embodiment of the present invention. [Figure 9] A schematic end view of a display device according to one embodiment of the present invention. [Figure 10] A schematic end view of a display device according to one embodiment of the present invention. [Figure 11] A schematic top view of a display device according to one embodiment of the present invention. [Figure 12] A schematic top view of a display device according to one embodiment of the present invention. [Figure 13] A schematic top view of the display device fabricated in the example. [Figure 14]A schematic top view of the display device fabricated in the example. [Modes for carrying out the invention]

[0007] The embodiments of the present invention will be described below with reference to the drawings and other materials. However, the present invention can be implemented in various forms without departing from its spirit, and is not to be interpreted as being limited to the embodiments described below.

[0008] While drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. In this specification and each figure, elements having the same function as those described in previously shown figures are denoted by the same reference numeral, and redundant explanations may be omitted. This reference numeral is used to represent multiple identical or similar structures collectively, and when representing them individually, a hyphen and a natural number are added after the reference numeral.

[0009] In this invention, when a single film is processed to form multiple films, these multiple films may have different functions and roles. However, these multiple films originate from a film formed as the same layer in the same process, and have substantially the same layer structure, the same material, and the same morphology. Therefore, these multiple films are defined as existing in the same layer.

[0010] In this specification and claims, when describing a manner in which one structure is placed on top of another structure, unless otherwise specified, the term "on top of" includes both cases: when one structure is placed directly on top of another structure so as to be in contact with it, and when another structure is placed above another structure via yet another structure.

[0011] In this specification and claims, the expression "a structure is exposed from another structure" means a portion of a structure that is not covered by another structure, and this portion that is not covered by another structure may also be covered by yet another structure. Furthermore, the expression also includes a portion of a structure that is not in contact with another structure.

[0012] 1. Overall configuration of the display device Figure 1 shows a schematic unfolded view of a display device 100 according to one embodiment of the present invention. The display device 100 is a liquid crystal display device having polymer-dispersed liquid crystal, and has an array substrate 106 and a counter substrate 108 facing the array substrate 106. Various patterned conductive films, insulating films, and semiconductor films are provided on the array substrate 106, and these are appropriately combined to provide a plurality of pixels 130, drive circuits for controlling the pixels 130 (gate line drive circuit 110, signal line drive circuit 112), terminals 114, etc. A light source 116 is further provided on the array substrate 106. The display device 100 is further provided with a pair of light guide plates 102 and 104 that sandwich the array substrate 106 and the counter substrate 108. The area on the array substrate 106 that surrounds all pixels 130 and adjacent pixels is called the display area, and the area surrounding the display area is called the frame area. These configurations will be described in detail below.

[0013] (1) Array substrate, opposing substrate, and light guide plate The array substrate 106 and the counter substrate 108 are both provided to impart physical strength to the display device 100 and to provide surfaces for supporting various components (for example, pixels 130, drive circuits, etc.) for realizing the functions of the display device. The array substrate 106 and the counter substrate 108 are both configured to transmit at least a part of visible light. Therefore, as the array substrate 106 and the counter substrate 108, a glass substrate, a quartz substrate, or a polymer substrate such as polyimide, polyamide, or polycarbonate can be used. The array substrate 106 and / or the counter substrate 108 may have flexibility. For example, the array substrate 106 and / or the counter substrate 108 may have flexibility to the extent of being elastically deformable, or may have flexibility to the extent of being plastically deformable. The array substrate 106 and the counter substrate 108 are fixed to each other using a sealing material not shown in FIG. 1. As understood from FIG. 1, a part of the array substrate 106 is exposed from the counter substrate 108, and the entire or a part of the drive circuit, the terminal 114, the light source 116, etc. are arranged on this exposed part.

[0014] Similar to the array substrate 106 and the counter substrate 108, the light guide plates 102 and 104 are also provided to impart physical strength to the display device 100 and, as will be described later, to efficiently supply the light from the light source 116 to the pixels 130. The light guide plates 102 and 104 are also configured to transmit visible light, and are configured to include, for example, glass, quartz, or the above-described polymers. The light guide plates 102 and 104 are fixed to the array substrate 106 and the counter substrate 108 respectively by an adhesive (not shown).

[0015] (2) Drive Circuit and Terminal The driving circuit is configured to control a plurality of pixels 130. As shown in FIG. 1, the whole or part of the driving circuit (for example, the gate line driving circuit 110) can be composed of a conductive film, a semiconductor film, and an insulating film patterned on the array substrate 106. In this case, the driving circuit is arranged and protected between the array substrate 106 and the counter substrate 108. Alternatively, the whole or part of the driving circuit (for example, the whole or part of the signal line driving circuit 112) may be formed by mounting an integrated circuit formed on a semiconductor substrate on the array substrate 106. In this case, the driving circuit is arranged on the array substrate 106 or on a connector described later so as to be exposed from the counter substrate 108.

[0016] The terminal 114 is formed by one or more conductive films patterned on the array substrate 106 and is exposed from the counter substrate 108. The terminal 114 is electrically connected to the driving circuit and is further connected to an external circuit (not shown) via a connector such as a flexible printed circuit (FPC) board not shown in FIG. 1. Thereby, power and various signals supplied from the external circuit are supplied to the driving circuit via the terminal 114. The driving circuit generates various control signals (for example, a gate signal, a video signal, a reset signal, etc.) for controlling the pixel 130 based on the supplied signals and supplies them to the pixel 130 via a gate line and a video signal line not shown in FIG. 1. Thereby, an image can be created on the display area.

[0017] (3) Pixel The pixel 130 functions as the minimum unit for giving color information and is provided on the array substrate 106. The pixels 130 are arranged in a matrix having a plurality of rows and a plurality of columns. Hereinafter, as shown in FIG. 1, the row direction is defined as the x direction and the column direction is defined as the y direction. The normal direction of the array substrate 106 is the z direction. When the array substrate 106 and / or the counter substrate 108 is rectangular, the x direction and the y direction can be set to be parallel to two mutually connected sides of the array substrate 106 and / or the counter substrate 108, respectively. Details regarding the configuration of the pixel 130 will be described later.

[0018] (4) Light source The light source 116 is provided on the array substrate 106 and is exposed from the opposing substrate 108. In other words, the light source 116 is arranged so as not to overlap with the display area in the z direction. The light source 116 has light-emitting elements that provide the three primary colors. More specifically, the light source 116 is provided with a plurality of red light-emitting elements, a plurality of green light-emitting elements, and a plurality of blue light-emitting elements. Each light-emitting element is composed of an organic electroluminescent element or an inorganic electroluminescent element, and preferably an inorganic electroluminescent element that emits light with high brightness and has a long element life is used. Although not shown in the figures, the plurality of light-emitting elements are arranged in the row direction. Furthermore, the light source 116 is configured so that the light emitted from the light-emitting elements is mainly emitted in the y direction (i.e., the column direction).

[0019] The driving method of the display device 100 can be set arbitrarily; for example, the display device 100 can be driven using a field sequential method. In this case, the light source 116 is configured such that light-emitting elements of different colors do not light up simultaneously, and multiple red light-emitting elements, multiple green light-emitting elements, and multiple blue light-emitting elements light up sequentially for each frame period. By adopting this method, all pixels 130 can function as units that provide red, green, and blue information, making full-color display possible without the need for a color filter.

[0020] Figure 2 shows a schematic end view of the display device 100. As will be described in detail later, a liquid crystal layer 166 containing polymer-dispersed liquid crystal is arranged in the space formed by the array substrate 106, the opposing substrate 108, and the sealing material 120 that fixes the array substrate 106 and the opposing substrate 108. Power and signals for driving the light source 116 are input to the light source 116 from the connector 118 via terminal 114, and based on these, the light-emitting element in the light source 116 emits light in the y direction. The emitted light is incident on the light guide plate 104, and some of it propagates in the y direction while repeatedly undergoing total internal reflection between the upper surface of the light guide plate 104 and the lower surface of the light guide plate 102 (see dotted arrow in Figure 2). At this time, the light scattering properties of the liquid crystal layer 166 are controlled by controlling the voltage applied to the liquid crystal layer 166 at each pixel 130. If the voltage applied to the liquid crystal layer 166 is controlled so that it transmits light rather than scatters it, light will be transmitted through the pixel 130 without scattering, and the light will undergo total internal reflection repeatedly. Therefore, the light from that pixel cannot be seen from the outside. However, because the pixel 130 transmits light, the background behind the display device can be seen. On the other hand, if the voltage applied to the liquid crystal layer 166 is controlled so that it scatters light, light will be scattered through the pixel 130 (see the solid arrow in Figure 2), and some of it will be emitted to the outside via the array substrate 106 and the light guide plate 102, or the opposing substrate 108 and the light guide plate 104. Therefore, color information can be obtained from the pixel 130. By utilizing this principle, various images can be created on the display area by appropriately combining pixels 130 in which the liquid crystal layer 166 scatters light. Furthermore, the liquid crystal layer 166 may be configured to scatter light from the light source 116 when a voltage is applied to the liquid crystal layer 166, or it may be configured to transmit light.

[0021] 2. Pixel structure (1) Basic Pixel Configuration The equivalent circuit diagram of pixel 130 is shown in Figure 3. Here, the equivalent circuit diagrams of two pixels 130 are shown. On the array substrate 106, multiple gate lines 122 extending from the gate line drive circuit 110 extend into the display area. On the other hand, multiple video signal lines 124 extending from multiple signal line drive circuits 112 extend into the display area. The multiple gate lines 122 and the multiple signal line drive circuits 112 intersect with each other. The area enclosed by two adjacent gate lines 122 and two adjacent video signal lines 124 is one pixel 130. Each pixel 130 is provided with a liquid crystal element 160 and a pixel circuit 132 electrically connected to the liquid crystal element 160. Each pixel circuit 132 is electrically connected to one of the multiple gate lines 122 and one of the multiple signal line drive circuits 112.

[0022] The configuration of the pixel circuit 132 can be arbitrarily determined, and it is sufficient that it includes at least one transistor 140 and at least one retaining capacitance element 134. In this case, the gate electrode of the transistor 140 is electrically connected to the gate line 122, and one terminal is connected to the video signal line 124. The other terminal of the transistor 140 is electrically connected to the liquid crystal element 160 (more specifically, the pixel electrode of the liquid crystal element 160 described later) and one electrode (capacitance electrode) of the retaining capacitance element 134. The other electrode of the liquid crystal element 160 (more specifically, the common electrode of the liquid crystal element 160 described later) and the retaining capacitance element 134 are electrically connected to a common wiring 126 to which a constant potential is supplied. As described above, there are no restrictions on the configuration of the pixel circuit 132. For this reason, although not shown in Figure 3, the pixel circuit 132 may be configured using multiple transistors or multiple retaining capacitance elements.

[0023] (2) Shape of the gate wire Schematic top views of a portion of the display device 100 are shown in Figures 4 and 5. These figures show a total of 20 pixels 130 arranged in a 5x4 grid, along with gate lines 122 and video signal lines 124 connected to these pixels 130. However, in Figure 5, the video signal lines 124 are shown as dotted lines. Also, for the sake of clarity, the individual components that make up the transistor 140 are not shown in these figures.

[0024] As shown in these figures, each gate line 122 is configured to have a zigzag shape when viewed from above. That is, although each gate line 122 extends in the x-direction (i.e., the row direction) as a whole, most of it is inclined from the x-direction, and the direction of extension is configured to change at a constant period. In addition, for each gate line 122, the angle θ between the direction in which a virtual straight line with adjacent bending points of the zigzag structure (black circles in Figure 5) as both endpoints extends and the x-direction is greater than 0° and less than 90°. As will be described later, adopting a zigzag structure prevents a decrease in display contrast and improves display quality. However, since the gate line 122 becomes longer, the load on the gate line 122 increases. Furthermore, if θ increases, the zigzag shape may be reflected in the contour of the image depending on the size of the pixel 130. Therefore, θ should be set considering the balance of these characteristics, and is preferably between 15° and 45°. Due to the shape of the gate line 122, the shape of each pixel 130 can be considered to be approximately a parallelogram. The bending points of the zigzag structure are the points where the extension directions of two adjacent straight sections, which have different extension directions and are inclined from the x-direction, intersect in each gate line 122. Each straight section has a length of at least the pitch P1 (see Figure 4) in the x-direction of the video signal line 124 and has a constant width.

[0025] As shown in Figure 5, the gate lines 122 are configured such that the bends in the zigzag structure are located between adjacent pixels 130 (i.e., diagonally opposite pixels 130) in a direction inclined from the x or y direction via the video signal lines 124. Therefore, each bend in the zigzag structure may overlap with any of the multiple video signal lines 124. In contrast, the video signal lines 124 extend almost along the y direction. For this reason, the distance D1 between adjacent bends (i.e., the length of the virtual straight line) is longer than the pitch P1 of the video signal lines 124 in the row direction. On the other hand, the pitch P2 of the bends in the x direction is the same as the pitch P1 of the video signal lines 124. By adopting this configuration, the bends in the zigzag structure can be positioned so as not to exist between adjacent video signal lines 124, but to overlap with the video signal lines 124.

[0026] (3) Arrangement of pixel circuits and liquid crystal elements Schematic top views of the display device 100 are shown in Figures 6 to 8, and schematic end views along the dashed lines AA' and BB' in Figure 7 are shown in Figures 9 and 10, respectively. For ease of viewing, Figure 6 does not show the capacitive electrodes of the retaining capacitance element 134 or the pixel electrodes constituting the liquid crystal element 160, but shows the main components constituting the gate line 122, the video signal line 124, and the transistor 140. Figure 7 is a schematic diagram of Figure 6 with the pixel electrode 162 added, and Figure 8 is a schematic diagram of Figure 6 with the capacitive electrode 136 of the retaining capacitance element 134 added.

[0027] As shown in Figure 6, a portion of the bent portion or its vicinity of the gate line 122, which has a zigzag structure, extends in the y direction and functions as the gate electrode 142 of the transistor 140. As shown in Figures 9 and 10, a gate insulating film 144 is provided on the gate electrode 142 so as to cover it, and a semiconductor film 146 that overlaps with the gate electrode 142 is laminated on the gate insulating film 144. On the other hand, as can be understood from Figures 6 and 7, a portion of the video signal line 124 overlaps with the gate electrode 142 and the semiconductor film 146, and is in contact with the semiconductor film 146 (Figures 9 and 10). This portion functions as the source electrode 148 of the transistor 140. Furthermore, a drain electrode 150 that overlaps with the gate electrode 142 and the semiconductor film 146 and is in the same layer as the video signal line 124 is provided so as to be in contact with the semiconductor film 146. The transistor 140 is composed of the gate electrode 142, gate insulating film 144, semiconductor film 146, source electrode 148, and drain electrode 150. By supplying a gate signal to the gate line 122, the transistor 140 of the pixel circuit 132 is turned on. In this state, by inputting a video signal via the video signal line 124, a potential corresponding to the video signal can be supplied to the liquid crystal element 160 via the transistor 140.

[0028] An interlayer insulating film 152, which also functions as a protective film, is provided on the transistor 140 in an arbitrary configuration, and further on top of that, a planarization film 154 is provided that absorbs irregularities caused by the pixel circuit 132 and gives a flat surface (Figures 9 and 10). The planarization film 154 is removed by etching in the region where the liquid crystal element 160 is provided, and in this region the interlayer insulating film 152 is exposed from the planarization film 154 (Figure 10). As shown in Figure 9, auxiliary wiring 170 for supplying potential to the retaining capacitance element 134 is provided on the planarization film 154 so as to overlap with the video signal line 124 and a part thereof, the source electrode 148.

[0029] The capacitive electrode 136 of the retaining capacitance element 134 is provided on the auxiliary wiring 170 so as to be in contact with the auxiliary wiring 170. At this time, the capacitive electrode 136 overlaps with the pixel electrode 162 of the liquid crystal element 160 and is provided so as to expose the contact hole (dotted circle in Figure 6, and see Figures 8 and 10) for contact between the drain electrode 150 and the pixel electrode 162. The capacitive electrode 136 is further provided across adjacent pixels 130 so as to be shared by all pixels 130 (see Figure 8). Although not shown, the auxiliary wiring 170 is connected to the common wiring 126 in the frame region, thereby supplying a constant potential. As will be described later, since the auxiliary wiring 170 is configured to include a metal such as aluminum, even if a relatively large area of ​​the capacitive electrode 136 is provided so as to be shared by all pixels 130, voltage drop of the capacitive electrode 136 can be prevented by arranging the capacitive electrode 136 in contact with the auxiliary wiring 170.

[0030] A capacitive insulating film 138 is provided on the capacitive electrode 136 and interlayer insulating film 152 of the retaining capacitance element 134, and furthermore, the pixel electrode 162 of the liquid crystal element 160 is formed on the capacitive insulating film 138. Contact holes are formed in the interlayer insulating film 152 and the capacitive insulating film 138 that expose the drain electrode 150, and an electrical connection is made between the pixel electrode 162 and the drain electrode 150 through these contact holes. This electrically connects the pixel circuit 132 and the liquid crystal element 160. Unlike the capacitive electrode 136, the pixel electrode 162 is formed for each pixel 130. Therefore, the potential of the pixel electrode 162 is controlled in each pixel 130. The pixel electrode 162 overlaps with the capacitive electrode 136 via the capacitive insulating film 138, and the retaining capacitance element 134 is composed of the capacitive electrode 136, the pixel electrode 162, and the capacitive insulating film 138 sandwiched between them. In other words, the pixel electrode 162 is shared by the liquid crystal element 160 and the retaining capacitance element 134. As shown in Figure 8, the capacitive electrode 136 may be provided with an aperture 136a that overlaps with the pixel electrode 162. By appropriately adjusting the size of the aperture 136a, the capacitance of the retaining capacitance element 134 can be adjusted.

[0031] A first alignment film 164-1 is provided on the pixel electrode 162. Meanwhile, a light-shielding film 156 is provided on the opposing substrate 108 (below the opposing substrate 108 in Figures 9 and 10; the same applies hereafter), overlapping with the pixel circuit 132, video signal lines 124, gate lines 122, etc. Furthermore, an opposing electrode 168 is provided so as to cover the light-shielding film 156, and a second alignment film 164-2 is positioned to cover the opposing electrode 168. A liquid crystal layer 166 containing polymer-dispersed liquid crystal is provided between the first alignment film 164-1 and the second alignment film 164-2. The liquid crystal element 160 is composed of the pixel electrode 162, the first alignment film 164-1, the liquid crystal layer 166, the second alignment film 164-2, and the opposing electrode 168.

[0032] The above-described configuration can be formed using known materials. Briefly, the gate line 122, video signal line 124, auxiliary wiring 170, etc., are configured to include metals such as molybdenum, tungsten, titanium, tantalum, aluminum, copper, or alloys containing metals selected from these. These configurations may have a single-layer structure or a laminated structure. Preferably, to reduce electrical resistance, the video signal line 124 and auxiliary wiring 170 are configured to include aluminum, for example, a titanium / aluminum / titanium laminated structure is employed.

[0033] The semiconductor film 146 may be composed of Group 14 elements, such as silicon, or it may be composed of an oxide semiconductor containing indium. There are no restrictions on the crystallinity of the semiconductor film 146; it may be amorphous or polycrystalline, but it is preferable to use a polycrystalline semiconductor film 146 to obtain higher carrier mobility. For example, if the semiconductor film 146 contains an oxide semiconductor or is composed of an oxide semiconductor, it is preferable that the semiconductor film 146 contains indium and metal elements other than indium. Examples of metal elements other than indium include gallium, zinc, aluminum, hafnium, yttrium, ziriconium, and lanthanide metals. The semiconductor film 146 containing an oxide semiconductor or composed of an oxide semiconductor can be formed by sputtering or atomic layer deposition (ALD).

[0034] The gate insulating film 144, the interlayer insulating film 152, the capacitance insulating film 138, etc., may consist of one or more layers containing silicon-containing inorganic compounds such as silicon oxide or silicon nitride. These films may be formed by sputtering or chemical vapor deposition (CVD). The planarization film 154 contains polymers such as polyimide, polyamide, acrylic resin, and epoxy resin, and is formed using methods such as spin coating, dip coating, printing, and inkjet. Similarly, the first alignment film 164-1 and the second alignment film 164-2 are also configured to contain polymers such as polyimide, and their surfaces are rubbed.

[0035] The capacitive electrode 136, the pixel electrode 162, and the counter electrode 168 are configured to transmit visible light. Therefore, these electrodes contain translucent oxides such as indium-tin oxide (ITO) or indium-zinc oxide (IZO) and are formed using methods such as sputtering. The light-shielding film 156 may be formed using a metal with low reflectivity to visible light, such as chromium, or a resin containing a black or similar colored pigment.

[0036] The liquid crystal layer 166 can be formed by injecting monomers containing liquid crystal molecules and liquid crystal units into the space (see Figure 2) formed by the array substrate 106, the opposing substrate 108, and the sealing material 120, and polymerizing the monomers. This makes it possible to obtain a polymer-dispersed liquid crystal as the liquid crystal layer 166, which has a structure in which the polymer network obtained from the monomers and the liquid crystal molecules are layer-separated.

[0037] As described above, transparent display devices use the scattering of light by the liquid crystal elements 160 of the pixels 130 to display images. Therefore, if light is scattered by components other than the liquid crystal elements 160, the display quality will deteriorate. In particular, unlike the video signal lines 124 which extend almost parallel to the direction of light emission from the light source 116, the gate lines 122 intersect with the video signal lines 124. Therefore, if light strikes the end face of the gate lines 122 perpendicularly, diffuse reflection of light is likely to occur. When such diffuse reflection of light occurs, for example, even in black displays, scattered light can be seen through the pixels 130, resulting in a decrease in image contrast.

[0038] However, in the display device 100, the gate line 122 has a zigzag structure, so the end face of the gate line 122 is oblique to the direction of light propagation. Furthermore, the gate line 122 can be positioned so that its bends coincide with the video signal line 124. As a result, as shown in the embodiment, scattering of light emitted from the light source 116 on the surface of the gate line 122 can be significantly suppressed, preventing a decrease in contrast and improving display quality. Therefore, by applying the embodiments of the present invention, it is possible to provide a display device capable of high-quality display and a transparent display device.

[0039] 3. Variant In the example described above, the pitch P2 in the x-direction of the zigzag structure of the gate line 122 is the same as the pitch P1 of the video signal line 124. However, the pitch P2 may be different from the pitch P1, for example, it may be an integer multiple (n times) of the pitch P1, where n is an integer. Specifically, as shown in Figures 11 and 12, the pitch P2 may be twice or three times the pitch P1. There is no restriction on the maximum value of n, but for example, an integer n between 1 and 4 is preferred. Even in such a configuration, the zigzag structure's bends can be positioned so as not to exist between adjacent video signal lines 124, but to overlap with the video signal lines 124. [Examples]

[0040] In this embodiment, we fabricated a display device with a gate line 122 of a different shape and described the results of investigating the effect of light scattering from the light source 116 on the gate line 122. Specifically, we fabricated a display device equipped with a gate line 122 having the structure shown in Figures 13 and 14. In the structure shown in Figure 13 (comparative example), the gate line 122 has no inflection points and extends linearly in the x direction. On the other hand, the structure shown in Figure 14 (example) is the structure of the gate line 122 in the display device 100 according to an embodiment of the present invention, where the pitch P2 in the x direction of the inflection points is the same as the pitch P1 of the video signal line 124, and the inflection points overlap with the video signal line 124. Also, the angle in the x direction with a virtual straight line having adjacent inflection points as both endpoints is 45°.

[0041] All pixels of the display devices in the example and comparative example were set to display black, and the brightness was measured at 10 measurement points for each display device, and the average brightness was calculated. As a result, when the brightness of the display device in the comparative example (Figure 13) was set to 1, the relative brightness of the display device in the example was 0.80. These results indicate that by applying the embodiment of the present invention, light leakage caused by light scattering on the gate line 122 is suppressed, and a display with higher contrast becomes possible.

[0042] As long as the embodiments described above as embodiments of the present invention do not contradict each other, they can be implemented in appropriate combinations. Also, based on each embodiment, those in which a person skilled in the art has appropriately added, deleted, or changed the design of components, or those in which the steps have been added, omitted, or the conditions have been changed, as long as they have the gist of the present invention, they are included in the scope of the present invention.

[0043] Even if there are other effects different from the effects brought about by the aspects of the above-described embodiments, those that are obvious from the description of this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention.

Description of Reference Numerals

[0044] 100: Display device, 102: Light guide plate, 104: Light guide plate, 106: Array substrate, 108: Counter substrate, 110: Gate line drive circuit, 112: Signal line drive circuit, 114: Terminal, 116: Light source, 118: Connector, 120: Sealing material, 122: Gate line, 124: Video signal line, 126: Common wiring, 130: Pixel, 132: Pixel circuit, 134: Holding capacitance element, 136: Capacitance electrode, 136a: Opening, 138: Capacitance insulating film, 140: Transistor, 142: Gate electrode, 144: Gate insulating film, 146: Semiconductor film, 148: Source electrode, 150: Drain electrode, 152: Interlayer insulating film, 154: Planarization film, 156: Light shielding film, 160: Liquid crystal element, 162: Pixel electrode, 164-1: First alignment film, 164-2: Second alignment film, 166: Liquid crystal layer, 168: Counter electrode, 170: Auxiliary wiring

Claims

1. Multiple gate lines, Multiple video signal lines that intersect with the aforementioned multiple gate lines, and Arranged in a matrix having multiple rows and multiple columns, each comprising multiple pixels electrically connected to one corresponding gate line and one corresponding video signal line, Each of the aforementioned plurality of gate lines has a zigzag shape, A display device in which the pitch of the zigzag-shaped inflection points in the row direction is an integer multiple of the pitch of the plurality of video signal lines in the row direction.

2. The pitch of the zigzag-shaped bending points in the row direction is n times the pitch of the plurality of video signal lines in the row direction. The display device according to claim 1, wherein n is selected from an integer between 1 and 4.

3. The display device according to claim 1, wherein the distance between adjacent inflection points is longer than the pitch of the plurality of video signal lines in the row direction.

4. The display device according to claim 1, wherein the inflection point coincides with one of the plurality of video signal lines.

5. The display device according to claim 1, wherein the inflection point is located between adjacent pixels in a direction inclined with respect to the row direction via the video signal line.

6. The display device according to claim 1, wherein each of the plurality of gate lines is configured such that the length of a virtual straight line ending at an adjacent bending point is longer than the pitch of the video signal lines in the row direction.

7. The display device according to claim 6, wherein the angle between the virtual line and the row direction is 15° or more and 45° or less.

8. The display device according to claim 1, wherein each of the plurality of pixels includes a liquid crystal element.

9. The display device according to claim 8, wherein the liquid crystal element has a polymer-dispersed liquid crystal.

10. The plurality of gate lines, the plurality of video signal lines, and the array substrate beneath the plurality of pixels, The array substrate further comprises a light source having a plurality of light-emitting elements, The display device according to claim 1, wherein the plurality of light-emitting elements are arranged parallel to the row direction.

11. The display device according to claim 10, wherein the light source is configured to sequentially emit light of the three primary colors.

Images