Patent Application
20160381317
The present invention relates to a display device and a television receiver.
A liquid crystal display device such as a liquid crystal television requires a separate backlight device as an illumination device since the liquid crystal panel, which is a display panel, does not emit light on its own, for example. LEDs, for example, are well-known as a light source used in such a backlight device. LEDs are broadly divided into a top-emitting type in which the surface opposite to the mounting surface to be mounted on a mounting substrate is the primary light-emitting surface, and a side-emitting type in which one of the side faces disposed upright on the mounting surface to be mounted on the mounting substrate is the primary light-emitting surface. Patent Document 1, for example, discloses a backlight unit that includes both such top-emitting LEDs and such side-emitting LEDs.
Backlight devices are broadly categorized into direct-lit and edge-lit types, depending on the configuration thereof. The backlight unit disclosed in Patent Document 1 is of the direct-lit type. In order to make the liquid crystal display device thinner, however, it is preferable to use a so-called “edge-lit backlight device” in which light from light sources disposed so as to face an end face of a light guide plate enters the end face of the light guide plate and then exits toward a display panel from one of the surfaces of the light guide plate.
When using LEDs as the light sources in an edge-lit backlight device, it is preferable to use top-emitting LEDs instead of side-emitting LEDs in order to ensure a high degree of brightness. In general, top-emitting LEDs have a higher rated value for forward current compared to side-emitting LEDs, and the amount of light emitted from the light-emitting surface is higher in top-emitting LEDs than in side-emitting LEDs. In addition, it is preferable to use a metal LED substrate instead of a non-metal LED substrate in order to ensure heat-dissipating characteristics. This is due to the fact that, while in side-emitting LEDs the surface to the rear of the light-emitting surface is not directly soldered onto the LED, top-emitting LEDs are disposed such that the surface to the rear of the light-emitting surface is attached to the LED substrate via direct soldering or the like; thus, heat is more effectively transmitted from the LEDs to the LED substrate in top-emitting LEDs than in side-emitting LEDs. As mentioned above, it is preferable in edge-lit backlight devices to use top-emitting LEDs disposed on a metal LED substrate in order to ensure a high degree of brightness and heat-dissipating characteristics.
In recent years, demand has increased for high-resolution liquid crystal panels and for liquid crystal panels with high color reproducibility. High-resolution liquid crystal panels include a large amount of wiring within the liquid crystal panel in order to increase the number of pixels, and liquid crystal panels with high color reproducibility require that color filters that form part of the liquid crystal panel be thicker in order to increase color purity; thus, transmittance in these types of liquid crystal panels is lower than in normal liquid crystal panels. As a result, there is demand to increase the brightness of the light emitted from the light sources toward the liquid crystal panel.
Thus, by disposing top-emitting LEDs, which are disposed in the above-described manner on a metal LED substrate, so as to face a plurality of end faces of the light guide plate, it is possible to increase the brightness of the light emitted from the light sources toward the liquid crystal panel while ensuring heat-dissipating characteristics. In an edge-lit backlight device, a mounting substrate on which the top-emitting LEDs are arranged is disposed in a vertical orientation inside a chassis. In addition, wiring patterns can be provided on only one surface of the metal mounting substrate, and the size of the surface of the mounting substrate is larger than in a case in which the mounting substrate is not made of metal. As a result, the display device is thicker in the area in which the top-emitting LEDs disposed on the metal LED substrate are arranged. Thus, when the top-emitting LEDs disposed on the metal LED substrate are disposed so as to face a plurality of end faces of the light guide plate, the respective areas where the LEDs are disposed become thicker, leading to the display device becoming thicker as a whole.
The technology disclosed in the present specification was made in view of the above-mentioned problems, and an aim thereof is to make a display device thinner while ensuring a high degree of brightness and heat-dissipating characteristics.
The technology disclosed in the present specification relates to a display device that includes: a chassis having at least a bottom plate; a display panel disposed on one surface side of the bottom plate; a flexible substrate that is flexible and bent such that one end side thereof is connected to the display panel and another end side reaches another surface side of the bottom plate; a signal transmission substrate that is connected to said another end side of the flexible substrate and disposed on said another surface side of the bottom plate, the signal transmission substrate transmitting signals to the flexible substrate; a light guide plate that is disposed between the display panel and the bottom plate and that emits light toward the display panel, an end face of the light guide plate facing the flexible substrate being a first light-receiving face and at least one other end face of the light guide plate being a second light-receiving face; first light sources of a top-emitting type disposed such that a light-emitting surface thereof faces the first light-receiving face of the light guide plate; second light sources of a side-emitting type disposed such that a light-emitting surface thereof faces the second light-receiving face of the light guide plate; a first light source substrate made of metal and supported by the bottom plate of the chassis, the first light sources being disposed on a surface of the first light source substrate; and a second light source substrate supported by the bottom plate of the chassis, the second light sources being disposed on a surface of the second light source substrate.
According to the above-described display device, the first light sources are of a top-emitting type and light enters at least two of the end faces of the light guide plate; thus, it is possible to increase the brightness of light exiting from the light guide plate toward the display panel compared to a configuration in which all of the light sources are of a side-emitting type or a configuration in which light is received at only one end face of the light guide plate. In addition, according to the above-described display device, while heat becomes concentrated in the area in which the signal transmission substrate is disposed as a result of heat generated by the first light sources and heat generated by a driving component that drives the display panel by processing signals from the signal transmission substrate, or the like, for example, the heat from the first light sources is effectively transmitted to the first light source substrate by having the first light sources be of the top-emitting type. Furthermore, by having the first light source substrate be made of metal and be supported by the bottom plate, it is possible to effectively transmit the heat generated by the first light sources and the driving component from the first light source substrate toward the bottom plate compared to a case in which the first light source substrate is not made of metal, and it is also possible to then dissipate the heat toward the outside of the display device.
Furthermore, the above-described display device is of a so-called “edge-lit” type in which light enters end faces of the light guide plate; thus, the first light source substrate is supported in a vertical orientation by the bottom plate since the first light sources are of the top-emitting type, and the second light source substrate is supported in a horizontal orientation by the bottom plate since the second light sources are of the side-emitting type. In addition, the first light source substrate is made of metal; thus, wiring patterns can be provided on only one surface of the first light source substrate and the size of the surface thereof will be larger than in a case in which the mounting substrate is not made of metal. Thus, the space in the thickness direction of the display device necessary to dispose the first light source substrate is larger than the space necessary to dispose the second light source substrate. Here, in the display device, a surface of the bottom plate of the chassis that is opposite to the side to which the light guide plate is disposed, or in other words, the above-mentioned other surface, is a surface that faces toward the exterior of the chassis. In addition, the signal transmission substrate is disposed on the other surface side of the bottom plate of the chassis; thus, the display device is thicker in the area in which the signal transmission substrate is disposed.
Thus, in the above-described display device, the first light source substrate is disposed in an area in which the display device is thicker as a result of the signal transmission substrate being disposed in the above-described manner; thus, it is possible for a thickness based on the arrangement of the signal transmission substrate to limit the effect of the disposition of the first light source substrate on the thickness of the display device. Meanwhile, in the area in which the second light source substrate is disposed, the display device will not become thicker since the second light source substrate is disposed horizontally in the above-described manner. Thus, it is possible for the display device as a whole to be made thinner. In the above-mentioned display device, it is possible in the manner described above to make the display device thinner while ensuring a high degree of brightness and heat-dissipating characteristics.
The first light sources may have a higher output than the second light sources. In the present specification, “higher output” refers to the driving power of the first light sources being higher than the driving power of the second light sources, and the amount of the light emitted from the first light sources being larger than the amount of light emitted from the second light sources.
Since the first light sources are of the top-emitting type and the first light source substrate is made of metal, even if the first light sources have a higher output, heat generated by the first light sources will be effectively transmitted to the first light source substrate and then transmitted to the bottom plate via the first light source substrate. Thus, it is possible to prevent heat buildup near the first light sources. According to the above-mentioned configuration, it is possible to increase the amount of light emitted from the first light sources while also ensuring heat-dissipating characteristics. By so doing, it is also possible to increase the brightness of light emitted from the light guide plate toward the display panel.
The first light source substrate may be disposed such that a portion thereof overlaps the signal transmission substrate in a direction orthogonal to the first light-receiving face.
According to such a configuration, it is possible to make the display device thinner in the area in which the signal transmission substrate and the first light source substrate are disposed.
The second light source substrate may be made of a flexible resin.
According to such a configuration, the second light source substrate can be made thinner compared to an instance in which the second light source substrate is made of a metal, and it is also possible to make the display device thinner in the area in which the second light source substrate is disposed.
At least a portion of the second light source substrate may be attached to a surface of the light guide plate such that the portion is sandwiched between the light guide plate and the bottom plate.
According to such a configuration, it is possible to use the second light source substrate to position the light guide plate with respect to the bottom plate.
A positioning portion that positions the light guide plate with respect to the bottom plate may be provided on an edge of the light guide plate near the first light-receiving face. In addition, a positioning portion that positions the light guide plate with respect to the first light source substrate may be provided on an edge of the light guide plate near the first light-receiving face.
According to such a configuration, it is possible to position the light guide plate with respect to the bottom plate at both the first light source side and the second light source side, and it is also possible to accurately position the light guide plate with respect to the bottom plate.
A pair of opposing end faces of the light guide plate may respectively be the first light-receiving face and the second light-receiving face, and the second light source substrate may have an abutting portion that abuts an end face of the light guide plate adjacent to the second light-receiving face, the abutting portion extending toward the first light source substrate from an end of the second light source substrate.
Since the second light source substrate is flexible, it is possible to have abutting portions abut the pair of opposing end faces of the light guide plate by folding the abutting portions. According to the above-mentioned configuration, it is possible to have the pair of opposing end faces of the light guide plate be sandwiched by the abutting portions, and it is possible to position the light guide plate with respect to the second light source substrate.
In such a configuration, light that reaches the abutting portions is reflected by the abutting portions; thus, it is possible to prevent light from leaking from the end faces adjacent to the second light-receiving face of the light guide plate.
The display device may further include a light source driving substrate that is disposed on said another surface side of the bottom plate and that provides driving power to the first light sources and the second light sources, a first wiring line may be connected to the first light source substrate, another end of the first wiring line being connected to the light source driving substrate, and a second wiring line may be connected to the abutting portion of the second light source substrate, another end of the second wiring line being connected to the light source driving substrate.
In such a configuration, as a result of the second wiring line being connected to the abutting portion that extends from the second substrate, it is possible to connect the first wiring line and the second wiring line to the light source driving substrate by drawing out both wiring lines to the other surface side of the bottom plate together. Thus, it is possible to easily draw out the wiring for driving the light sources.
The first wiring line and the second wiring line may be connected to the light source driving substrate via the signal transmission substrate.
In such a configuration, it is possible to shorten the drawn-out length of the first wiring line and the second wiring line compared to a configuration in which the first wiring line and the second wiring line are drawn out all the way to the light source driving substrate, and it is thus possible to simply draw out the respective wiring lines.
The chassis may have a side wall that rises from an edge of the bottom plate toward the display panel, and the display device may further include a first heat-dissipating member that contacts the first light source substrate and the side wall while being sandwiched therebetween.
In such a configuration, heat that was transmitted to the first light source substrate is transmitted toward the bottom plate of the chassis and is also transmitted toward the side wall of the chassis via the first heat-dissipating member; thus, it is possible to increase the heat-dissipating characteristics from the first light source substrate toward the chassis.
The display device may further include a second heat-dissipating member that contacts the bottom plate and the signal transmission substrate while being sandwiched therebetween.
In such a configuration, the heat transmitted toward the chassis from the first light sources and the heat generated by the signal transmission substrate can be effectively dissipated to the outside of the display device via the second heat-dissipating member.
In the technology disclosed in the present specification, a display device in which the display panel is a liquid crystal panel that uses liquid crystal is also novel and useful. Furthermore, a television receiver that includes the above-described display device is also novel and useful.
An aim of the technology disclosed in the present specification is to make a display device thinner while ensuring a high degree of brightness and heat-dissipating characteristics.
Embodiment 1 will be described with reference to the drawings. In the present embodiment, a liquid crystal display device (one example of a display device) 10 will be described as an example. Each of the drawings indicates an X axis, a Y axis, and a Z axis in a portion of the drawings, and each of the axes indicates the same direction in the respective drawings. The X axis direction corresponds to the horizontal direction, the Y axis direction corresponds to the vertical direction, and the Z axis direction corresponds to the thickness direction (front-rear direction). In
A television receiver TV includes: the liquid crystal display device 10; front and rear cabinets CA, CB that house the liquid crystal display device 10 therebetween; a power source P; a tuner T; and a stand S. The liquid crystal display device 10 has a horizontally-long quadrangular shape as a whole, and includes a liquid crystal panel 11 that is a display panel, and a backlight device 12 that is an external light source. These are integrally held together by a component such as a bezel 13 having a frame-like shape. In the liquid crystal display device 10, the liquid crystal panel 11 is assembled with a display surface 11C, which is capable of displaying images, facing toward the front. As shown in
The bezel 13 is made of a metal with excellent rigidity such as stainless steel, and, as shown in
The configuration of the backlight device 12 will be explained next. As shown in
The light guide plate 18 is made of a synthetic resin material (an acrylic resin such as PMMA, or a polycarbonate, for example) that has a refractive index sufficiently higher than that of air and that is almost completely transparent (has excellent light transmissivity). As shown in
One of the two long-side end faces of the light guide plate 18 is a first light-receiving face 18A1 that receives light emitted from the first LED unit 20A, and the other of the two long-side end faces is a second light-receiving face 18A2 that receives light emitted from the second LED unit 20B. Of these, the first light-receiving face 18A1 faces toward the side of the liquid crystal display device 10 on which source-side flexible substrates 30, which will be described later, are disposed. The light guide plate 18 is disposed such that: the pair of light-receiving faces 18A1, 18A2 respectively face the respective LED units 20A, 20B; a light-exiting surface 18B, which is the main surface (front surface), faces toward the optical sheets 16; and an opposite surface 18C, which is the surface (rear surface) on the side opposite of the light-exiting surface 18B, faces toward the reflective sheet 21. A light guide plate 18 with such a configuration receives light emitted from the respective LED units 20A, 20B at the respective light-receiving faces 18A1, 18A2, propagates the light therein, orients the light upward toward the optical sheets 16, and then emits the light from the light-exiting surface 18B.
Cutout portions (one example of a positioning portion) 18D, which have a recessed shape and respectively recede toward the inside (the center of the light guide plate 18), are provided in both short-side end faces of the light guide plate 18 near the first light-receiving face 18A1 edge of each short-side end face. As shown in
The reflective sheet 21 is a rectangular sheet-shaped member, is made of a synthetic resin, and the front surface thereof is white with excellent light-reflecting characteristics. The long-side direction of the reflective sheet 21 corresponds to the X axis direction, the short-side direction thereof corresponds to the Y axis direction, and the reflective sheet 21 contacts the light guide plate 18 and the chassis 15 while being sandwiched therebetween. The reflective sheet 21 is able to reflect light that has leaked from the respective LED units 20A, 20B or the light guide plate 18 toward the front surface of the reflective sheet 21. As shown in
As shown in
The chassis 15 forms the rear exterior of the liquid crystal display device 10. The chassis 15 is made of a metal such as aluminum, and as shown in
As shown in
As shown in
The first LED substrate 25A forming part of the first LED unit 20A is made of aluminum that has excellent heat-dissipating characteristics, and as shown in
On the inner surface of the first LED substrate 25A, or in other words, on the surface facing the light guide plate 18 (the face opposing the light guide plate 18), the first LEDs 24A having the configuration described above are surface-mounted, and this surface is considered to be the mounting surface. The respective first LEDs 24A are directly soldered onto the mounting surface of the first LED substrate 25A such that the light-emitting surface 24A1 thereof faces the light-receiving face 18A1 of the light guide plate 18. A plurality of the first LEDs 24A are disposed in a row (a straight line) at substantially the same pitch along the lengthwise direction (X axis direction) of the mounting surface of the first LED substrate 25A. A wiring pattern (not shown) made of a metal film (such as copper foil) is formed on the mounting surface of the first LED substrate 25A. The wiring pattern extends along the X axis direction and connects adjacent first LEDs 24A in series by going across the group of first LEDs 24A. Driving power is provided to the first LEDs 24A by having terminals formed at both ends of the wiring pattern be connected to an LED driving substrate (not shown) via a wiring member such as a connector or electric wiring. As shown in
As shown in
The second LED substrate 25B that forms part of the second LED unit 20B is formed of a synthetic resin material (a polyimide resin or the like, for example) that has insulating properties, is formed via a flexible film-shaped base material, and is disposed close to the second light-receiving face 18A2 edge of the light guide plate 18. The second LED substrate 25B has a horizontally-long rectangular shape in a plan view, and is supported in a horizontal orientation by the bottom plate 15A of the chassis 15. Specifically, the second LED substrate 25B is disposed such that the long-side direction thereof corresponds to the X axis direction and the short-side direction thereof corresponds to the Y axis direction. The front surface of the second LED substrate 25B is the face that faces the liquid crystal panel 11 (faces toward the front) and is the face on which the second LEDs 24B are disposed upright. The rear surface of the second LED substrate 25B faces toward the bottom plate 15A of the chassis 15. Approximately half of the second LED substrate 25B that is closer to the inside in the short-side direction thereof (the part closer to the center of the light guide plate 18) contacts the bottom plate 15A of the chassis 15 and the edge of the opposite surface 18C of the light guide plate 18 that is closer to the second light-receiving face 18A2 while being sandwiched therebetween. The approximately half of the second LED substrate 25B that contacts the light guide plate 18 is attached to the opposite surface 18C of the light guide plate 18 via adhesive tape or the like (not shown). In order to improve the reflection efficiency of the second LED substrate 25B, a white resist may be formed on the front surface of the second LED substrate 25B.
A plurality of the second LEDs 24B disposed upright on the front surface of the second LED substrate 25B are disposed in parallel along the long-side direction (X axis direction) of the second LED substrate 25B. The respective second LEDs 24B are disposed upright on the front surface of the second LED substrate 25B via an LED attachment member (not shown) such that the light-emitting surface 24B1 thereof faces the second light-receiving face 18A2 of the light guide plate 18. Wiring lines are connected to a portion of the two long-side ends of the second LED substrate 25B at a tip thereof. By having the other end of the wiring lines be electrically connected to an LED driving substrate or the like (not shown), power is provided to the second LEDs 24B and the driving of the second LEDs 24B is controlled.
The frame 14 is formed in a horizontally-long frame-like shape similar to the shape of the bezel 13 and is made of a synthetic resin (a polycarbonate or polyethylene terephthalate, for example). The frame 14 is formed of a frame framing section 14A that is parallel to the liquid crystal panel 11 and that has a substantially frame-like shape in a plan view, and frame cylindrical sections 14B that respectively extend in a substantially short-tube like shape from the peripheral edges of the frame framing section 14A toward the front and rear sides. The frame framing section 14A extends along the edges of the light-exiting surface 18B of the light guide plate 18, and sandwiches the light guide plate 18 between the bottom plate 15A of the chassis 15 and the frame framing section 14A by pressing upon the edges of the light-exiting surface 18B from the front. Cushioning material 26B is disposed between the frame framing section 14A and the liquid crystal panel 11. The frame framing section 14A supports the edges of the liquid crystal panel 11 from the rear via the cushioning material 26B. The length of the portion of the frame cylindrical section 14B that extends toward the rear from the peripheral edges of the frame framing section 14A is longer than the length of the portion that extends toward the front. The portion that extends toward the rear forms a portion of the exterior of the side faces of the liquid crystal display device 10 by being provided on a large portion of the first side wall 15B1 and second side wall 15B2 of the chassis 15. In addition, a recessed driver housing section 14B1 is provided in the portion of the frame cylindrical section 14B provided on the first side wall 15B1. The recessed driver housing section 14B1 opens toward the outside (the side opposite to the side that is next to the first side wall 15B1) and houses a source driver SD, which will be explained later (see
The configuration of the liquid crystal panel 11 will be explained next. As shown in
Capacitance wiring lines (auxiliary capacitance wiring lines, storage capacitance wiring lines) that are parallel to the gate wiring lines and overlap the pixel electrodes in a plan view are provided on the array substrate 11A. The capacitance wiring lines and the gate wiring lines are alternately arranged in a line along the Y axis direction. Meanwhile, the following are provided on the CF substrate 11B: color filters having respective colored portions such as R (red), G (green), and B (blue) arranged in a prescribed pattern, an opposite electrode, an alignment film, and the like. This liquid crystal panel 11 is divided into a display region that is provided toward the center of the screen of the display surface 11C and that can display images, and a non-display region that is located at the peripheral edges of the screen covered by the bezel frame section 13A of the bezel 13 and that forms a frame-like shape that surrounds the display region. Polarizing plates (not shown) are disposed to the outside of both substrates 11A, 11B.
As shown in
As shown in
The length of the source-side flexible substrate 30 extending from the array substrate 11A of the liquid crystal panel 11 is longer than that of the gate-side flexible substrate 28. As shown in
A source substrate (one example of a signal transmission substrate) 32 is disposed on a portion of the rear surface side of the bottom plate 15A of the chassis 15 (see
A plurality of wiring patterns (not shown) are formed on an inward-facing (facing toward the chassis 15) surface of the source-side flexible substrate 30. One end of these wiring patterns is connected to the source-side terminals of the liquid crystal panel 11, and the other end is connected to the source substrate 32. The source-side flexible substrate 30 is of a one surface-mounting type in which the wiring patterns and the source driver SD are selectively mounted on only one surface. On the inner surface of the source-side flexible substrate 30, an insulating film is formed so as to cover a large portion of the wiring pattern (except for both ends), thereby insulating the wiring patterns.
A portion (a middle portion) of the wiring pattern between the one end and the other end is connected the source driver SD mounted on the inner surface of the source-side flexible substrate 30. As shown in
In addition, by having the source driver SD not contact the driver housing section 14B1 in this manner, a large portion of the heat generated in the source driver SD when the source driver SD is driven is transmitted to the mounting portion 30C of the source-side flexible substrate 30 on which the source driver SD is mounted. As shown in
As shown in
As shown in
In the liquid crystal display device 10 of the present embodiment that has the above-mentioned configuration, light is received at two end faces (the first light-receiving face 18A1 and the second light-receiving face 18A2) of the light guide plate 18; thus, it is possible to increase the brightness of light emitted from the light guide plate 18 toward the liquid crystal panel 11 compared to a configuration in which light is received at only one end face of the light guide plate 18. In addition, the first LEDs 24A are of the top-emitting type; thus, the amount of light received by the light guide plate 18 is higher than in a configuration in which all of the LEDs are of the side-emitting type, and it is possible to increase the brightness of light emitted from the light guide plate 18 toward the liquid crystal panel 11 compared to a configuration in which light is received at only one end face of the light guide plate 18.
In addition, in the liquid crystal display device 10 of the present embodiment, heat becomes concentrated in the area in which the source substrate 32 is disposed, or in other words, near the first light-receiving face 18A1 of the light guide plate 18, as a result of heat generated by the first LEDs 24A and heat generated by the source driver SD. As a countermeasure, in the present embodiment, the first LEDs 24A are of the top-emitting type; thus, the first LEDs 24A are directly soldered onto the first LED substrate 25A, and the contact area between the LEDs and the LED substrate is larger than in a configuration in which the first LEDs 24A are of the side-emitting type. Thus, heat is effectively transmitted from the first LEDs 24A to the first LED substrate. Furthermore, the first LED substrate 25A is made of aluminum and is supported by the bottom plate 15A of the chassis 15; thus, it is possible for heat generated by the first LEDs 24A to be effectively transmitted from the first LED substrate 25A toward the bottom plate 15A compared to a case in which the first LED substrate 25A is not made of metal. As a result, in the liquid crystal display device 10 of the present embodiment, it is possible to effectively dissipate heat that becomes concentrated near the first light-receiving face 18A1 as a result of the addition of heat generated by the source driver SD, with the heat being effectively dissipated to the outside of the liquid crystal display device 10 via the bottom plate 15A of the chassis 15.
Furthermore, the liquid crystal display device 10 of the present embodiment is configured to include an edge-lit backlight device 12; thus, the first LED substrate 25A is supported in a vertical orientation by the bottom plate 15A of the chassis 15 since the first LEDs 24A are of the top-emitting type, and the second LED substrate 25B is supported in a horizontal orientation by the bottom plate 15A of the chassis 15 since the second LEDs 24B are of the side-emitting type. In addition, the first LED substrate 25A is made of aluminum, or in other words, made of metal; thus, wiring patterns can be provided on just one surface of the first LED substrate 25A, and the size of the surface of the first LED substrate 25A is larger than in a case in which the first LED substrate 25A is not made of metal. Thus, the space in the thickness direction (Z axis direction) of the liquid crystal display device 10 necessary to dispose the first LED substrate 25A is larger than the space necessary to dispose the second LED substrate 25B.
The source substrate 32 is disposed on the rear surface side of the bottom plate 15A of the chassis 15; thus, the thickness (the dimension in the Z axis direction) of the liquid crystal display device 10 is larger in the area where the source substrate 32 is disposed (the area near the first light-receiving face 18A1). As a countermeasure, in the liquid crystal display device 10 of the present embodiment, the first LED substrate 25A is disposed in the area in which the liquid crystal display device 10 is thicker as a result of the source substrate 32 being disposed in the above-described manner. Thus, having the thickness based on the disposition of the source substrate 32 makes it possible to limit the effect of the disposition of the first LED substrate 25A on the thickness of the liquid crystal display device 10. Meanwhile, in the area in which the second LED substrate 25B is disposed, the liquid crystal display device 10 will not become thicker since the second LED substrate 25B is disposed horizontally in the above-described manner. Thus, it is possible to make the liquid crystal display device 10 thinner overall.
In the liquid crystal display device 10 of the present embodiment described above, it is possible to increase the brightness of light emitted from the light guide plate 18 toward the liquid crystal panel 11; thus, it is possible to realize a higher degree of brightness even when the liquid crystal panel 11 is a high-resolution liquid crystal panel as in the present embodiment. In addition, even in a configuration such as that of the present embodiment in which heat becomes concentrated in the area in which the source substrate 32 is disposed as a result of LEDs being disposed in the same area, it is possible to effectively dissipate heat to the outside of the liquid crystal display device 10 in the above-described manner. Furthermore, in the liquid crystal display device 10 of the present embodiment, it is possible to prevent the liquid crystal display device 10 from becoming thicker in areas (such as the area where the second LED substrate 25B is disposed) other than the area where the source substrate 32 is disposed, while also limiting the effect of the disposition of the first LED substrate 25A on the thickness of the liquid crystal display device 10 in the area in which the source substrate 32 is disposed. As a result, in the liquid crystal display device 10 of the present embodiment, it is possible to make the liquid crystal display device 10 thinner while ensuring heat-dissipating characteristics and a high degree of brightness.
In addition, in the liquid crystal display device 10 of the present embodiment, the first LEDs 24A have a higher output than the second LEDs 24B. In other words, the driving power of the first LEDs 24A is larger than the driving power of the second LEDs 24B, and the amount of light emitted from the first LEDs 24A is larger than the amount of light emitted from the second LEDs 24B. Also, since the first LEDs 24A are of the top-emitting type and the first LED substrate 25A is made of aluminum, even if the first LEDs 24A have a higher output as described above, heat generated by the first LEDs 24A will be effectively transmitted to the first LED substrate 25A and then transmitted to the bottom plate 15A of the chassis 15 via the first LED substrate 25A. Thus, it is possible to prevent heat buildup near the first LEDs 24A. In this manner, it is possible to increase the amount of light emitted from the first LEDs 24A while also ensuring heat-dissipating characteristics. By so doing, it is also possible to increase the brightness of light emitted from the light guide plate 18 toward the liquid crystal panel 11.
In addition, in the liquid crystal display device 10 of the present embodiment, a portion of the first LED substrate 25A is disposed so as to overlap the source substrate 32 in a direction (the Y axis direction) orthogonal to the first light-receiving face 18A1. By using such a configuration, it is possible to make the liquid crystal display device 10 thinner in the area in which the source substrate 32 and the first LED substrate 25A are disposed.
In addition, in the liquid crystal display device 10 of the present embodiment, the second LED substrate 25B is made of a flexible synthetic resin. As a result, there is a degree of freedom in regards to the drawing-out configuration of the wiring lines, such as using multiple layers of wiring lines, and there is also a degree of freedom with respect to the shape of the second LED substrate 25B; thus, by doing things such as making the reflective sheet 21 and the second LED substrate 25B have the same thickness, it is possible to make the liquid crystal display device 10 even thinner in the area in which the second LED substrate 25B is disposed.
In addition, in the liquid crystal display device 10 of the present embodiment, the light guide plate 18 is positioned with respect to the bottom plate 15A by having the respective protrusions 15C engage the respective cutout portions 18D near the first light-receiving face, and the light guide plate 18 is also positioned with respect to the bottom plate 15A via the second LED substrate 25B by having a portion of the second LED substrate 25B be attached to the opposite surface 18C of the light guide plate 18 near the second light-receiving face. By using such a configuration, it is possible to more accurately position the light guide plate 18 with respect to the bottom plate 15A compared to configuration in which only a central portion of the light guide plate 18 is positioned with respect to the bottom plate 15A, for example.
Next, a modification example of Embodiment 1 will be described with reference to
In the plan view shown in
Embodiment 2 will be described with reference to the drawings. Embodiment 2 differs from Embodiment 1 in that the configuration of the second LED substrate 125B and the drawing-out configuration of the various wiring lines that connect the respective LED substrates 125A, 125B to the LED driving substrate 134 are different. Other configurations are similar to those of Embodiment 1; thus, descriptions of the configurations, operation, and effects thereof are omitted.
As shown in
As shown in
In addition, in the present embodiment, the second LED substrate 125B has light-reflecting characteristics as a result of the white resist being formed on the second LED substrate 125B in the above-described manner; thus, in a state in which the respective abutting portions 125B2 abut both short-side end faces of the light guide plate 118, light that has passed through the light guide plate 118 and reached both short-side end faces of the light guide plate 118 is reflected by the respective abutting portions 125B2 and once again enters the light guide plate 118. As a result, it is possible to prevent light leakage from both short-side end faces of the light guide plate 118.
Also in the present embodiment, as shown in
In the present embodiment, as shown in
Next, a modification example of Embodiment 2 will be described with reference to
In the present modification example, first LED substrate-side wiring lines (one example of first wiring lines) CN3 are connected to one end of the first LED substrate in the long-side direction (X axis direction) thereof, and second LED substrate-side wiring lines (one example of second wiring lines) CN4 are connected to a portion of the abutting portion of the second LED substrate. As shown in
In the present modification example, as a result of the respective wiring lines CN3, CN4, CN5, CN6 having the above-described drawing-out configuration, the first LED substrate-side wiring lines CN3, CN5 and the second LED substrate-side wiring lines CN4, CN6 are connected to the LED driving substrate 134 via the source substrate 132. Thus, compared to a configuration in which the first LED substrate-side wiring lines CN3, CN5 and the second LED substrate-side wiring lines CN4, CN6 are drawn out all the way to the LED driving substrate 134, it is possible to shorten the drawn-out length of the first LED substrate-side wiring lines CN3, CN5 and the second LED substrate-side wiring lines CN4, CN6, and it is also possible to simply draw out the respective wiring lines CN3, CN4, CN5, CN6.
Embodiment 3 will be described with reference to the drawings. Embodiment 3 differs from Embodiment 1 in the arrangement and number of second LED units 220B. Other configurations are similar to those of Embodiment 1 and Embodiment 1, and therefore, descriptions of the configurations, operation, and effects thereof will be omitted. Parts in
As shown in
In the present embodiment, by using the above-mentioned configuration, light from first LEDs 224A is received by a first light-receiving face 218A1, and light from the second LEDs 224B is received by the respective second light-receiving faces 218A2, resulting in light being received at three of the end faces of the light guide plate 218. Thus, it is possible to increase the brightness of light emitted from a light-exiting surface 218B of the light guide plate 218.
Modification examples of the respective above-mentioned embodiments are described below.
(1) In the respective above-mentioned embodiments, a configuration was used as an example in which the second LED substrate was made of a synthetic resin. However, a configuration in which the second LED substrate is made of a metal such as aluminum may also be used. Even in such a case, the second LED substrate is disposed in a horizontal orientation with respect to the bottom plate of the chassis; thus, it is possible to make the liquid crystal display device thinner.
(2) In the respective above-mentioned embodiments, a configuration was used as an example in which one or two end faces of the end faces of the light guide plate (excluding the end face facing the source substrate) were second light-receiving faces. However, a configuration in which three of the end faces (excluding the end face facing the source substrate) are all second light-receiving faces may also be used. In such a case, light is received at all of the end faces of the light guide plate; thus, it is possible to further increase the brightness of the light emitted from the light-exiting surface of the light guide plate.
(3) In the respective above-mentioned embodiments, a configuration was used as an example in which a portion of the second light source substrate was attached to the opposite surface of the light guide plate. A configuration in which a portion of the second light source substrate is not attached to the light guide plate may also be used, however, and there are no restrictions regarding the assembly configuration of the second light source substrate with respect to the light guide plate.
(4) In the respective above-mentioned embodiments, a configuration was used an example in which a positioning portion for positioning the light guide plate with respect to the bottom plate of the chassis was provided near the first light-receiving face of the light guide plate. There are no restrictions regarding the configuration of the positioning portion, however.
(5) In the respective above-mentioned embodiments, a high-resolution liquid crystal panel was used as an example. The present invention can also be applied to a display panel that does not have high resolution, however. For example, even if the liquid crystal panel is a liquid crystal panel with high color reproducibility, by applying the present invention, it is possible to make the display device thinner while ensuring a high degree of brightness and heat-dissipating characteristics.
(6) In the respective above-mentioned embodiments, an example was used of a television receiver that included a cabinet. The present invention can also be applied in a television receiver that does not include a cabinet, however.
(7) In the respective above-mentioned embodiments, an example was used of a television receiver that included a high-resolution liquid crystal panel. The present invention can also be applied in a display device other than a television receiver, however.
Respective embodiments of the present invention were described in detail above, but these are merely examples, and do not limit the scope as defined by the claims. The technical scope defined by the claims includes various modifications of the specific examples described above.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-056070 | Mar 2014 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2015/054551 | 2/19/2015 | WO | 00 |
