WO2013008779A1 - Backlight device, display device, and television receiver - Google Patents

Abstract

Provided are an LED substrate (light source substrate) (6) on which a plurality of light-emitting diodes (light sources) (5) are installed, and an installation surface (attachment plate) (9b) on which the LED substrate (6) is installed, and which is for attaching the LED substrate (6). Narrowed sections (heat dissipation structures) (9b1) that dissipate heat from the light-emitting diodes (5) are disposed between two adjacent light-emitting diodes (5) on the installation surface (9b).

Description

Backlight device, display device, and television receiver

The present invention relates to a backlight device, a display device using the backlight device, and a television receiver.

In recent years, for example, in a television receiver for home use, as represented by a liquid crystal display device, a display device provided with a liquid crystal panel as a flat display portion having many features such as a thinner and lighter than a conventional cathode ray tube. Is becoming mainstream. Such a liquid crystal display device includes a backlight device that emits light, and a liquid crystal panel that displays a desired image by acting as a shutter for light from a light source provided in the backlight device. It has been. In the television receiver, information such as characters and images included in the video signal of the television broadcast is displayed on the display surface of the liquid crystal panel.

In addition, as the backlight device, an edge light type or a direct type is provided in which a linear light source composed of a cold cathode tube or a hot cathode tube is disposed on the side or below the liquid crystal panel. However, the above-described cold cathode tubes and the like contain mercury, and it is difficult to recycle the discarded cold cathode tubes. Therefore, a backlight device using a light emitting diode (LED) that does not use mercury as a light source has been developed and put into practical use.

In addition, as described in, for example, Patent Document 1 below, a conventional backlight device includes a plurality of light emitting diodes (light sources) with respect to a side surface portion of a casing constituting an outer container of the backlight device. While installing the installed LED board, the heat sink was installed with respect to the bottom face part of a housing | casing. And in this conventional backlight apparatus, it was supposed that the heat which generate | occur | produced in the light emitting diode could be thermally radiated efficiently.

JP 2006-267936 A

However, the conventional backlight device as described above has a problem that the number of parts of the backlight device increases because the heat sink is installed on the bottom surface of the casing. In addition, in this conventional backlight device, it is necessary to perform a work process for assembling the heat sink, and the heat sink itself is expensive, which causes a problem that the cost of the backlight device is greatly increased.

In view of the above problems, the present invention provides an inexpensive backlight device that can efficiently dissipate heat from a light source while preventing an increase in the number of components, a display device using the backlight device, and a television receiver. The purpose is to provide.

To achieve the above object, a backlight device according to the present invention includes a plurality of light sources,
A light source substrate on which the plurality of light sources are installed;
The light source board is installed, and includes a mounting plate for mounting the light source board,
The mounting plate is provided with a heat radiating structure for radiating heat from the light source between two adjacent light sources.

In the backlight device configured as described above, the light source substrate is installed, and an attachment plate for attaching the light source substrate is provided. The mounting plate is provided with a heat dissipation structure between two adjacent light sources. Thus, unlike the conventional example, it is possible to configure a low-cost backlight device that can efficiently dissipate heat from the light source while preventing an increase in the number of components.

Further, in the backlight device, it is preferable that the mounting plate is provided with an installation portion where the light source substrate is installed so as to face the installation portion of the light source on the light source substrate.

In this case, the heat generated by the light source can be reliably transmitted to the heat dissipation structure via the light source substrate and the installation portion, and heat can be radiated more efficiently.

Further, in the backlight device, it is preferable that the mounting plate is provided with a facing surface that is opposite to the light source substrate and is opposed to the installation portion at a predetermined distance.

In this case, it is possible to allow air to come into contact with the installation portion, and heat generated by the light source can be radiated more efficiently.

In the backlight device, a diaphragm portion provided so as to protrude from the installation portion to the side opposite to the light source substrate may be used as the heat dissipation structure.

In this case, the surface area of the mounting plate can be increased by the diaphragm portion, and the heat generated by the light source can be radiated more efficiently.

In the backlight device, an opening provided between two adjacent installation portions may be used as the heat dissipation structure.

In this case, the light source substrate can be directly exposed to the air through the opening, and the heat generated by the light source can be radiated more efficiently.

Further, in the backlight device, a diaphragm portion provided so as to protrude from the installation portion to the side opposite to the light source substrate and an opening portion provided in the diaphragm portion may be used as the heat dissipation structure. Good.

In this case, the surface area of the mounting plate can be increased by the diaphragm, and the light source substrate can be directly exposed to the air by the opening, so that the heat generated by the light source can be radiated more efficiently.

In the backlight device, a flexible printed board may be used as the light source board.

In this case, a light source substrate having excellent heat dissipation is used, and heat generated by the light source can be radiated more efficiently.

In the backlight device, an aluminum substrate may be used as the light source substrate.

In this case, a light source substrate having excellent heat dissipation is used, and heat generated by the light source can be radiated more efficiently.

In the backlight device, aluminum may be used as the mounting plate.

In this case, a mounting plate having excellent heat dissipation is used, and heat generated by the light source can be radiated more efficiently.

Further, in the backlight device, the light source, and a housing for accommodating at least the light source substrate,
It is preferable that the mounting plate is configured using a side surface portion of the housing.

In this case, a compact backlight device with a small number of parts can be easily configured.

In the backlight device, it is preferable that a light emitting diode is used as the light source.

In this case, a backlight device with low power consumption and excellent environmental characteristics can be easily configured.

The display device of the present invention is characterized by using any one of the above backlight devices.

Also, the television receiver of the present invention is characterized by using the above display device.

In the display device and the television receiver configured as described above, an inexpensive backlight device that can efficiently dissipate heat from the light source while preventing an increase in the number of components is used. Therefore, it is possible to easily configure a display device and a television receiver that are low in performance and low in cost.

According to the present invention, it is possible to provide an inexpensive backlight device that can efficiently dissipate heat from a light source while preventing an increase in the number of components, a display device using the backlight device, and a television receiver. It becomes possible.

FIG. 1 is an exploded perspective view for explaining a television receiver and a liquid crystal display device according to a first embodiment of the present invention. FIG. 2 is a diagram for explaining a main configuration of the liquid crystal display device. FIG. 3 is a diagram for explaining the configuration of the liquid crystal panel shown in FIG. FIG. 4 is a plan view showing the main configuration of the backlight device shown in FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a plan view showing a main configuration of a backlight device according to the second embodiment of the present invention. 7 is a cross-sectional view taken along line VII-VII in FIG. FIG. 8 is a plan view showing the main configuration of the backlight device according to the third embodiment of the present invention. 9 is a cross-sectional view taken along line IX-IX in FIG.

Hereinafter, preferred embodiments of the backlight device, the display device, and the television receiver of the present invention will be described with reference to the drawings. In the following description, the case where the present invention is applied to a transmissive liquid crystal display device will be described as an example. Moreover, the dimension of the structural member in each figure does not faithfully represent the actual dimension of the structural member, the dimensional ratio of each structural member, or the like.

[First Embodiment]
FIG. 1 is an exploded perspective view for explaining a television receiver and a liquid crystal display device according to a first embodiment of the present invention. In the figure, the television receiver Tv of the present embodiment includes a liquid crystal display device 1 as a display device, and is configured to be able to receive a television broadcast by an antenna, a cable (not shown) or the like. The liquid crystal display device 1 is erected by a stand D while being housed in the front cabinet Ca and the back cabinet Cb. In the television receiver Tv, the display surface 1a of the liquid crystal display device 1 is configured to be visible through the front cabinet Ca. The display surface 1a is installed by the stand D so as to be parallel to the direction of action of gravity (vertical direction).

Further, in the television receiver Tv, an image corresponding to a television broadcast video signal received by a TV tuner unit (not shown) is displayed on the display surface 1a, and audio is output from a speaker Ca1 provided in the front cabinet Ca. Is played out. The back cabinet Cb is formed with a large number of ventilation holes so that heat generated by the backlight device, the power source, etc. can be appropriately dissipated.

Subsequently, the liquid crystal display device 1 of the present embodiment will be specifically described with reference to FIG.

FIG. 2 is a diagram for explaining a main configuration of the liquid crystal display device.

2, the liquid crystal display device 1 of the present embodiment includes a liquid crystal panel 2 in which the upper side of FIG. 2 is installed as a viewing side (display surface side), and a non-display surface side of the liquid crystal panel 2 (lower side of FIG. 2). And the backlight device 3 of the present invention that generates illumination light for illuminating the liquid crystal panel 2 is provided. Further, in the liquid crystal display device 1, the liquid crystal panel 2 and the backlight device 3 are assembled with each other inside the bezel 4 having an L-shaped cross section, and illumination light from the backlight device 3 enters the liquid crystal panel 2. The transmissive liquid crystal display device 1 is integrated.

Further, in the liquid crystal display device 1, a control device 12 that controls driving of each part of the liquid crystal display device 1 is installed on the backlight device 3 side (back cabinet Cb) side. The control device 12 includes a panel control unit 13 that performs drive control of the liquid crystal panel 2 and a backlight control unit 14 that performs drive control of the backlight device 3.

In the liquid crystal display device 1, the display surface 1 a is defined by a rectangular opening 4 a provided in the bezel 4. That is, in the liquid crystal display device 1, the display surface of the liquid crystal panel 2 visually recognized through the opening 4a constitutes the display surface 1a.

The liquid crystal panel 2 is provided with a liquid crystal layer, a color filter substrate and an active matrix substrate as a pair of substrates sandwiching the liquid crystal layer, and an outer surface of each of the color filter substrate and the active matrix substrate. A polarizing plate is provided (not shown). In the liquid crystal panel 2, the polarization state of the illumination light incident via the polarizing plate on the backlight device 3 side is modulated by the liquid crystal layer, and the polarizing plate on the opening 4 a side (display surface 1 a side) is used. A desired image is displayed by controlling the amount of light passing therethrough.

Next, the liquid crystal panel 2 of the present embodiment will be specifically described with reference to FIG.

FIG. 3 is a diagram for explaining the configuration of the liquid crystal panel shown in FIG.

3, the liquid crystal display device 1 (FIG. 2) includes the panel control unit 13 that performs drive control of the liquid crystal panel 2 (FIG. 2) as a display unit that displays information such as characters and images, and the panel control. A source driver 15 and a gate driver 16 that operate based on an instruction signal from the unit 13 are provided.

The panel control unit 13 is provided in the control device 12 (FIG. 2) provided in the liquid crystal display device 1, and receives a video signal from the outside of the liquid crystal display device 1. . Further, the panel control unit 13 performs predetermined image processing on the input video signal to generate each instruction signal to the source driver 15 and the gate driver 16, and the input video signal. A frame buffer 13b capable of storing display data for one frame included. Then, the panel control unit 13 performs drive control of the source driver 15 and the gate driver 16 according to the input video signal, so that information according to the video signal is displayed on the liquid crystal panel 2.

The source driver 15 and the gate driver 16 are installed on the active matrix substrate, for example. Specifically, the source driver 15 is installed on the surface of the active matrix substrate so as to be along the lateral direction of the liquid crystal panel 2 in the outer area of the effective display area A of the liquid crystal panel 2 as a display panel. Further, the gate driver 16 is installed on the surface of the active matrix substrate so as to be along the vertical direction of the liquid crystal panel 2 in the outer region of the effective display region A.

The source driver 15 and the gate driver 16 are driving circuits that drive a plurality of pixels P provided on the liquid crystal panel 2 side by pixel, and the source driver 15 and the gate driver 16 include a plurality of source lines S1 to S1. SM (M is an integer of 2 or more, hereinafter collectively referred to as “S”) and a plurality of gate wirings G1 to GN (N is an integer of 2 or more, hereinafter collectively referred to as “G”). Each is connected. These source wiring S and gate wiring G constitute a data wiring and a scanning wiring, respectively, on a transparent glass material or a transparent synthetic resin substrate (not shown) included in the active matrix substrate. They are arranged in a matrix so as to cross each other. That is, the source wiring S is provided on the substrate so as to be parallel to the matrix-like column direction (vertical direction of the liquid crystal panel 2), and the gate wiring G is arranged in the matrix-like row direction (horizontal of the liquid crystal panel 2). Is provided on the substrate so as to be parallel to (direction).

Further, in the vicinity of the intersection between the source line S and the gate line G, the thin film transistor 17 as a switching element and the pixel P having the pixel electrode 18 connected to the thin film transistor 17 are provided. In each pixel P, the common electrode 19 is configured to face the pixel electrode 18 with the liquid crystal layer provided on the liquid crystal panel 2 interposed therebetween. That is, in the active matrix substrate, the thin film transistor 17, the pixel electrode 18, and the common electrode 19 are provided for each pixel.

In the active matrix substrate, a plurality of pixels P are formed in each region partitioned in a matrix by the source wiring S and the gate wiring G. The plurality of pixels P include red (R), green (G), and blue (B) pixels. These RGB pixels are sequentially arranged in this order, for example, in parallel with the gate wirings G1 to GN. Further, these RGB pixels can display corresponding colors by a color filter layer (not shown) provided on the color filter substrate side.

In the active matrix substrate, the gate driver 16 scans the gate wirings G1 to GN based on the instruction signal from the image processing unit 13a (gate signal for turning on the gate electrode of the corresponding thin film transistor 17). Signal) in sequence. Further, the source driver 15 sends a data signal (voltage signal (gradation voltage)) corresponding to the luminance (gradation) of the display image to the corresponding source wirings S1 to SM based on the instruction signal from the image processing unit 13a. Output.

Subsequently, the backlight device 3 of the present embodiment will be specifically described with reference to FIGS. 2, 4, and 5.

FIG. 4 is a plan view showing a main configuration of the backlight device shown in FIG. 5 is a cross-sectional view taken along line VV in FIG. In FIG. 4, the bending surface 9 d is omitted from the side surface portion of the housing 9 for simplification of the drawing.

First, the basic configuration of the backlight device 3 of the present embodiment will be specifically described with reference to FIGS. 2 and 4.

As shown in FIGS. 2 and 4, the backlight device 3 of this embodiment includes a light emitting diode 5 as a light source, an LED substrate 6 as a light source substrate on which the light emitting diode 5 is mounted, and a light emitting diode 5. A light guide plate 7 into which light enters is provided. As the light emitting diode 5, for example, a white (W) light emitting diode that emits white light is used. Further, in the backlight device 3 of the present embodiment, as illustrated in FIG. 4, two LED substrates 6 are used, and each LED substrate 6 has a plurality of, for example, six, arranged in a straight line. The light emitting diodes 5 are installed at a predetermined interval from each other. Further, a printed circuit board using a synthetic resin such as an epoxy resin is used for the LED board 6.

The light guide plate 7 is made of, for example, a synthetic resin such as a transparent acrylic resin, and is configured to receive light from the light emitting diode (light source) 5. That is, in the light guide plate 7, the two side surfaces facing each other function as a light incident surface 7 a that receives light from the light emitting diode 5. The light guide plate 7 is configured to emit the light of the light emitting diode 5 that has entered from the light incident surface 7 a toward the liquid crystal panel 2 from the emission surface 7 b that is provided to face the liquid crystal panel 2. ing. That is, the light guide plate 7 guides the light from the light emitting diode 5 in a predetermined propagation direction (left-right direction in FIG. 2), and from the emission surface 7b to the liquid crystal panel (irradiated object) 2 as an irradiated object. Light is emitted.

Further, on the opposite side of the light guide plate 7 from the liquid crystal panel 2, for example, a reflection sheet 8 is installed so that the light use efficiency from the light emitting diode 5 can be improved. The reflection sheet 8 is provided inside the housing 9 so as to contact the bottom surface portion 9 a of the housing 9.

Further, in the backlight device 3 of the present embodiment, an optical sheet 11 such as a lens sheet or a diffusion sheet is provided on the liquid crystal panel 2 side (outgoing surface 7 b side) of the light guide plate 7. The light from the light emitting diode 5 guided in the propagation direction is changed to the planar illumination light having a uniform luminance and applied to the liquid crystal panel 2.

Further, as shown in FIG. 2, the backlight device 3 of the present embodiment is provided with a bottomed casing 9 having an opening on the liquid crystal panel 2 side, a rectangular opening, and an edge of the casing 9. And a P (plastic) chassis 10 attached to the part. The optical sheet 11 is disposed in the opening of the P chassis 10 so that the light from the emission surface 7b (FIG. 4) of the light guide plate 7 is increased in brightness and incident on the liquid crystal panel 2. It has become.

For example, a metal material such as aluminum is used for the housing 9, and the housing 9 is erected with respect to the bottom surface portion 9a at four sides of the flat bottom surface portion 9a and the bottom surface portion 9a. It has a side part. The housing 9 is configured to accommodate at least the light emitting diode 5 and the LED substrate 6. Further, in the housing 9, the reflection sheet 8 and the light guide plate 7 are sequentially placed on the bottom surface portion 9 a. It has become so.

Moreover, in the said side part, the side part (side part of the side of the right and left side of FIG. 4) of the edge | side which opposes the LED board 6 and the side part of the side which does not oppose the LED board 6 (side surface of the upper and lower side of FIG. 4) Are formed in different shapes.

Specifically, in the side surface portion, the side surface portion of the side facing the LED substrate 6 is provided on the LED substrate 6 side, and the installation surface 9b on which the LED substrate 6 is installed, and the installation surface 9b. And a bending surface 9d provided so as to be substantially orthogonal to the installation surface 9b and the opposing surface 9c. As shown in FIG. ing. On the other hand, the side portion of the side that does not face the LED substrate 6 is configured only by the installation surface 9b.

Further, in the backlight device 3 of the present embodiment, the installation surface 9b, the facing surface 9c, and the bending surface 9d included in the side surface portion of the side facing the LED substrate 6 among the side surface portions are the same as those of the present embodiment. A mounting plate is configured, and an LED substrate (light source substrate) 6 is installed, and the LED substrate 6 is mounted in the backlight device 3. That is, in the backlight device 3 of the present embodiment, the LED substrate 6 is attached using an attachment plate having a U-shaped cross section.

Subsequently, the configuration of the main part of the backlight device 3 of the present embodiment will be described with reference to FIG.

As shown in FIGS. 4 and 5, the installation surface 9 b is provided with a diaphragm portion 9 b 1 as a heat dissipation structure and an installation portion 9 b 2 facing the light emitting diode 5. On the installation surface 9b, the LED substrate 6 is installed on the surface on the light guide plate 7 side through an attachment member (not shown) such as a double-sided tape or a screw. In addition, on the installation surface 9b, as shown in FIG. 4, the installation portion 9b2 on which the LED board 6 is installed is provided so as to face the installation part of the light emitting diode 5 on the LED board 6. Further, as shown in FIG. 5, the installation surface 9b is provided with the facing surface 9c facing the installation portion 9b2 on the side opposite to the LED substrate 6 with a predetermined distance.

As shown in FIG. 4, the aperture portion 9b1 is provided so as to protrude from the installation portion 9b2 to the side opposite to the LED substrate 6 between at least two adjacent light emitting diodes 5. More specifically, on the installation surface 9b, there are five diaphragms 9b1 provided between the two adjacent light emitting diodes 5 and outside the left and right light emitting diodes 5 (left side and right side). Two provided throttle portions 9b1 are formed.

Further, the diaphragm portion 9b1 is provided continuously with the installation portion 9b2, and is provided so as to be parallel to the installation portion 9b2 between the inclined surface 9b1a inclined to the facing surface 9c side and the two inclined surfaces 9b1a. Parallel planes 9b1b. And in the aperture | diaphragm | squeeze part 9b1, it is comprised so that the surface area of the installation surface 9b may be enlarged and the heat | fever from the light emitting diode 5 transmitted to the installation surface 9b via the LED board 6 from the light emitting diode 5 can be radiated more efficiently. ing.

In the backlight device 3 of the present embodiment configured as described above, an LED substrate (light source substrate) 6 is installed, and an installation surface 9b, an opposing surface 9c, and a mounting plate for mounting the LED substrate 6 are provided. And the bending surface 9d is provided. In addition, on the installation surface 9b, a diaphragm portion (heat dissipation structure) 9b1 is provided between two adjacent light emitting diodes 5. Thereby, in the backlight apparatus 3 of this embodiment, unlike the said prior art example, the heat | fever which generate | occur | produced in the light emitting diode 5 can be thermally radiated efficiently, without providing heat radiating members, such as a heat sink. Therefore, in the present embodiment, unlike the conventional example, it is possible to configure the backlight device 3 at a low cost that can efficiently dissipate heat from the light emitting diode 5 while preventing an increase in the number of components.

Further, in the present embodiment, the diaphragm portion 9b1 provided so as to protrude from the installation portion 9b2 to the opposite side of the LED substrate 6 is used as the heat dissipation structure, so that the surface area of the installation surface 9b is reduced by the diaphragm portion 9b1. The heat generated in the light emitting diode 5 can be radiated more efficiently.

Further, according to the experiment result by the inventor of the present invention, by providing the throttle portion 9b1 as described above, the surface area of the installation surface 9b is increased by 10 to 20% compared to the case where the throttle portion 9b1 is not provided. In this case, it was confirmed that the temperature in the vicinity of the light emitting diode 5 at the time of lighting is reduced by about 5 ° C. Further, it has been demonstrated that this temperature decrease extends the life of the light-emitting diode 5 by about 10,000 to 20000 hours.

In the present embodiment, the installation surface 9b is provided with an installation portion 9b2 on which the LED substrate 6 is installed so as to face the installation portion of the light emitting diode 5 on the LED substrate 6. Thereby, in this embodiment, the heat generated in the light emitting diode 5 can be reliably transmitted to the throttle portion (heat dissipating structure) 9b1 via the LED substrate 6 and the installation portion 9b2, and heat can be radiated more efficiently. it can.

Moreover, in this embodiment, since the opposing surface 9c which opposes the installation part 9b2 on the opposite side to the LED substrate 6 and at a predetermined distance is provided, air is provided to the installation part 9b2. The heat generated in the light emitting diode 5 can be dissipated more efficiently.

In the present embodiment, since the inexpensive backlight device 3 that can efficiently dissipate heat from the light emitting diode (light source) 5 while preventing an increase in the number of components is used, the number of components is small. The liquid crystal display device (display device) 1 and the television receiver Tv that are high performance and low in cost can be easily configured.

[Second Embodiment]
FIG. 6 is a plan view showing a main configuration of a backlight device according to the second embodiment of the present invention. 7 is a cross-sectional view taken along line VII-VII in FIG. In the figure, the main difference between the present embodiment and the first embodiment is that a slit (opening) provided between two adjacent installation portions is used as the heat dissipation structure. In addition, about the element which is common in the said 1st Embodiment, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted. Further, in FIG. 6, the bending surface 20 d is omitted from the side surface portion of the housing 20 for simplification of the drawing.

That is, in FIGS. 6 and 7, in the backlight device 3 of the present embodiment, a bottomed casing 20 having an opening on the liquid crystal panel 2 side is used. For example, a metal material such as aluminum is used for the housing 20, and the housing 20 is erected with respect to the bottom surface portion 20 a at a flat bottom surface portion 20 a and four sides of the bottom surface portion 20 a. It has a side part. Moreover, the housing | casing 20 is comprised so that the light emitting diode 5 and the LED board 22 may be accommodated at least, and also in the housing | casing 20, the reflective sheet 8 and the light-guide plate 7 are mounted in order on the bottom face part 20a. It has become so.

Moreover, in the said side part, like 1st Embodiment, the side part (side part of the side of the right-and-left side of FIG. 6) of the edge | side which opposes the LED board 22, and the side part (side part of the side which does not oppose LED board 22) The side portions of the upper and lower sides in FIG. 6 are formed in different shapes.

Specifically, in the side surface portion, the side surface portion of the side facing the LED substrate 22 is provided on the LED substrate 22 side, and the installation surface 20b on which the LED substrate 22 is installed, and the installation surface 20b. And a bending surface 20d provided so as to be substantially orthogonal to the installation surface 20b and the opposing surface 20c. As shown in FIG. ing. On the other hand, the side surface portion of the side that does not face the LED substrate 22 is configured only by the installation surface 20b.

Further, in the backlight device 3 of the present embodiment, the installation surface 20b, the facing surface 20c, and the bending surface 20d included in the side surface portion of the side facing the LED substrate 22 among the side surfaces are the same as those of the present embodiment. An attachment plate is configured, and an LED substrate (light source substrate) 22 is installed, and the LED substrate 22 is attached in the backlight device 3. That is, in the backlight device 3 of the present embodiment, the LED substrate 22 is mounted using a mounting plate having a U-shaped cross section, as in the first embodiment.

For example, a flexible printed circuit board (FPC) is used for the LED board 22 so that heat generated in the light emitting diode 5 can be easily dissipated.

6 and 7, the installation surface 20b is provided with an installation part 20b1 facing the light emitting diode 5 and a slit 20b2 as a heat dissipation structure. Further, on the installation surface 20b, the LED substrate 22 is installed on the surface on the light guide plate 7 side via an attachment member such as a double-sided tape or a screw (not shown). Further, on the installation surface 20b, as shown in FIG. 6, the installation portion 20b1 on which the LED substrate 22 is installed is provided so as to face the installation portion of the light emitting diode 5 on the LED substrate 22. Further, as shown in FIG. 7, the installation surface 20b is provided with the facing surface 20c that faces the installation portion 20b1 on the side opposite to the LED board 22 and is opposed to the installation surface 20b1 at a predetermined distance.

The slit 20b2 is configured by an opening that opens the installation surface 20b. As shown in FIG. 6, the slit 20b2 is provided between at least two adjacent light emitting diodes 5, that is, between two adjacent installation parts 20b1. Yes. Specifically, the installation surface 20b is provided with five slits 20b2 provided between two adjacent light emitting diodes 5 and outside (left and right) of the left and right light emitting diodes 5 respectively. The two slits 20b2 thus formed are formed.

With the above configuration, the present embodiment can achieve the same operations and effects as the first embodiment. Moreover, in this embodiment, the slit (opening part) 20b2 provided between the two adjacent installation parts 20b1 is used as a heat dissipation structure. Thereby, in this embodiment, the LED substrate (light source substrate) 22 can be directly exposed to the air by the slit 20b2, and the heat generated in the light emitting diode (light source) 5 can be radiated more efficiently. In addition, in the installation surface 20b, it is preferable that the opening area of the slit 20b2 is less than or equal to ½ of the contact area of the installation surface 20b that contacts the LED substrate 22. That is, with this configuration, the heat generated in the light-emitting diode 5 can be sufficiently transmitted from the LED substrate 22 to the installation surface 20b, and can be appropriately radiated.

Moreover, in this embodiment, since the flexible printed circuit board is used as the LED board 22, the LED board 22 which has the outstanding heat dissipation will be used, and the heat | fever generated in the light emitting diode 5 is radiated more efficiently. can do.

[Third Embodiment]
FIG. 8 is a plan view showing the main configuration of the backlight device according to the third embodiment of the present invention. 9 is a cross-sectional view taken along line IX-IX in FIG. In the figure, the main difference between the present embodiment and the first embodiment is that a diaphragm and a slit (opening) provided in the diaphragm are used as the heat dissipation structure. In addition, about the element which is common in the said 1st Embodiment, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted. Further, in FIG. 8, the bending surface 21 d is omitted from the side surface portion of the housing 21 for the sake of simplification.

That is, in FIGS. 8 and 9, in the backlight device 3 of the present embodiment, a bottomed casing 21 having an opening on the liquid crystal panel 2 side is used. For example, a metal material such as aluminum is used for the casing 21. The casing 21 is erected with respect to the bottom surface portion 21a by a flat bottom surface portion 21a and four sides of the bottom surface portion 21a. It has a side part. Moreover, the housing | casing 21 is comprised so that the light emitting diode 5 and the LED board 23 may be accommodated at least, and also in the housing | casing 21, the reflective sheet 8 and the light-guide plate 7 are mounted in order on the bottom face part 21a. It has become so.

Moreover, in the said side part, the side part (side part of the side of the right-and-left side of FIG. 6) of the edge | side which opposes the LED board 23, and the side part of the edge | side which does not oppose the LED board 23 similarly to 1st Embodiment. The side portions of the upper and lower sides in FIG. 6 are formed in different shapes.

Specifically, in the side part, the side part of the side facing the LED board 23 is provided on the LED board 23 side, and the installation surface 21b on which the LED board 23 is installed, and the installation surface 21b. And a bent surface 21d provided so as to be substantially orthogonal to the installation surface 21b and the opposing surface 21c, as shown in FIG. ing. On the other hand, the side portion of the side that does not face the LED substrate 23 is configured only by the installation surface 21b.

Further, in the backlight device 3 of the present embodiment, the installation surface 21b, the facing surface 21c, and the bending surface 21d included in the side surface portion of the side facing the LED substrate 23 among the side surface portions are the same as those of the present embodiment. An attachment plate is configured, and an LED substrate (light source substrate) 23 is installed, and the LED substrate 23 is attached in the backlight device 3. That is, in the backlight device 3 of the present embodiment, the LED substrate 23 is mounted using a mounting plate having a U-shaped cross section, as in the first embodiment.

For example, an aluminum substrate is used for the LED substrate 23 so that the heat generated in the light emitting diode 5 can be easily dissipated.

As shown in FIGS. 8 and 9, the installation surface 21 b is provided with a diaphragm portion 21 b 1 as a heat dissipation structure and an installation portion 21 b 2 facing the light emitting diode 5. Moreover, in this installation surface 21b, the LED board 23 is installed with respect to the surface by the side of the light-guide plate 7 through attachment members, such as a double-sided tape or a screw which is not shown in figure. Further, on the installation surface 21b, as shown in FIG. 8, the installation portion 21b2 on which the LED substrate 23 is installed is provided so as to face the installation portion of the light emitting diode 5 on the LED substrate 23. Further, as shown in FIG. 9, the installation surface 21b is provided with the facing surface 21c that faces the installation portion 21b2 on the side opposite to the LED substrate 23 at a predetermined distance.

As shown in FIG. 8, the aperture portion 21b1 is provided so as to protrude from the installation portion 21b2 to the side opposite to the LED substrate 23 between at least two adjacent light emitting diodes 5. Specifically, on the installation surface 21b, there are five diaphragms 21b1 provided between two adjacent light emitting diodes 5 and outside (left and right sides) of the left and right light emitting diodes 5 respectively. Two provided throttle portions 21b1 are formed.

Further, the diaphragm portion 21b1 is provided continuously with the installation portion 21b2, and is provided so as to be parallel to the installation portion 21b2 between the inclined surface 21b1a inclined to the facing surface 21c side and the two inclined surfaces 21b1a. Parallel plane 21b1b. The parallel surface 21b1b is provided with a slit 21b1c formed by an opening that opens the parallel surface 21b1b. And in the aperture | diaphragm | squeeze part 21b1, while increasing the surface area of the installation surface 21b, the LED board 23 is directly exposed to air by the slit 21b1c, and it is comprised so that the heat | fever from the light emitting diode 5 can be thermally radiated more efficiently.

With the above configuration, the present embodiment can achieve the same operations and effects as the first embodiment. Further, in the present embodiment, as the heat dissipation structure, a diaphragm part 21b1 provided so as to protrude from the installation part 21b2 to the opposite side of the LED substrate (light source board) 23, and a slit (opening) provided in the diaphragm part 21b1 Part) 21b1c is used. As a result, in the present embodiment, the surface area of the installation surface 21b can be increased by the throttle portion 21b1, and the LED substrate 23 can be directly exposed to the air by the slit 21b1c, and the heat generated in the light-emitting diode 5 can be further increased. Heat can be radiated efficiently.

In this embodiment, since the aluminum substrate is used as the LED substrate 23, the LED substrate 23 having excellent heat dissipation is used, and the heat generated in the light emitting diode 5 is radiated more efficiently. be able to.

It should be noted that all of the above embodiments are illustrative and not restrictive. The technical scope of the present invention is defined by the claims, and all modifications within the scope equivalent to the configurations described therein are also included in the technical scope of the present invention.

For example, in the above description, the case where the present invention is applied to a transmissive liquid crystal display device has been described. However, the backlight device of the present invention is not limited to this, and a transflective liquid crystal display device, or The present invention can be applied to various display devices such as a projection display device using a liquid crystal panel as a light valve.

In addition to the above explanation, the present invention is installed on a light box for illuminating X-ray film or photographic negatives for irradiating light to make it easy to see, or on a signboard or a wall in a station. It can be suitably used as a backlight device of a light emitting device that illuminates advertisements and the like.

Further, in the above description, a case where a plurality of light emitting diodes (light sources) arranged in a straight line is opposed to the two side surfaces of the light guide plate facing each other is described. The light device is not limited to this. For example, the light device may be one in which a light source is opposed to one side surface of the light guide plate. Further, a plurality of rows of light sources may be arranged to face one side surface of the light guide plate.

In the above description, the case where the mounting plate is configured using the side surface portion of the housing has been described. However, the mounting plate of the present invention is not limited to this, and a light source substrate is installed. In addition, there is no limitation as long as the light source substrate is attached.

However, as in each of the above-described embodiments, when the mounting plate is configured using the side surface portion of the housing, it is easier to configure a compact backlight device with fewer parts. It is preferable in that it can be performed.

In the above description, the case where aluminum is used as the mounting plate (side surface portion of the housing) has been described. However, the mounting plate of the present invention is not limited to this, and other metals, A synthetic resin or the like can also be used.

However, as in each of the above embodiments, when using aluminum as the mounting plate, a mounting plate having excellent heat dissipation is used, and heat generated by the light source is radiated more efficiently. It is preferable in that it can be performed.

In the above description, a case where a white light emitting diode is used as the light source has been described. However, the light source of the present invention is not limited to this, and a discharge tube such as a cold cathode fluorescent tube or a hot cathode fluorescent tube is used. A light source such as a lamp such as a light bulb or a light emitting element such as an organic EL (Electronic Luminescence) or an inorganic EL element can also be used as a light source.

However, it is preferable to use a light-emitting diode as a light source as in the above-described embodiments in that a backlight device with low power consumption and excellent environmental characteristics can be easily configured.

The light-emitting diode of the present invention is not limited to the white light-emitting diode described above. For example, a so-called 3-in-1 type light-emitting diode in which RGB light-emitting diodes are integrated, and four light-emitting diodes such as RGBW and GRGB are integrated. It is also possible to use so-called four-in-one (4 in 1) type light-emitting diodes or R, G, B single-color individual light-emitting diodes.

The present invention is useful for an inexpensive backlight device that can efficiently dissipate heat from a light source while preventing an increase in the number of parts, a display device using the backlight device, and a television receiver.

1 Liquid crystal display device (display device)
2 LCD panel (irradiated object)
3 Backlight device 5 Light emitting diode (light source)
6, 22, 23 LED board (light source board)
9 Housing 9b Installation surface (mounting plate, side surface)
9b1 Restriction part (heat dissipation structure)
9b2 Installation part 9c Opposing surface (mounting plate, side part)
9d Bending surface (mounting plate, side surface)
20 Housing 20b Installation surface (mounting plate, side surface)
20b1 installation part 20b2 slit (heat dissipation structure, opening)
20c Opposing surface (mounting plate, side surface)
20d Bending surface (mounting plate, side surface)
21 Housing 21b Installation surface (mounting plate, side surface)
21b1 Restriction part (heat dissipation structure)
21b1c slit (heat dissipation structure, opening)
21b2 Installation part 21c Opposing surface (mounting plate, side part)
21d Bending surface (mounting plate, side surface)
Tv TV receiver

Claims (13)

Multiple light sources;
A light source substrate on which the plurality of light sources are installed;
The light source board is installed, and includes a mounting plate for mounting the light source board,
The mounting plate is provided with a heat dissipation structure that dissipates heat from the light source between two adjacent light sources.
A backlight device characterized by that. The backlight device according to claim 1, wherein the mounting plate is provided with an installation portion on which the light source substrate is installed so as to face an installation portion of the light source on the light source substrate. 3. The backlight device according to claim 2, wherein the mounting plate is provided with a facing surface that is opposite to the light source substrate and faces the installation portion at a predetermined distance. 4. The backlight device according to claim 2, wherein a diaphragm portion provided so as to protrude from the installation portion to the side opposite to the light source substrate is used as the heat dissipation structure. 5. The backlight device according to claim 2, wherein an opening provided between the two adjacent installation portions is used as the heat dissipation structure. 4. The diaphragm according to claim 2, wherein an aperture provided in the diaphragm and an aperture provided in the diaphragm are used as the heat dissipation structure so as to protrude from the installation unit to the side opposite to the light source substrate. Backlight device. The backlight device according to claim 1, wherein a flexible printed circuit board is used as the light source substrate. The backlight device according to any one of claims 1 to 6, wherein an aluminum substrate is used as the light source substrate. The backlight device according to any one of claims 1 to 8, wherein aluminum is used as the mounting plate. A housing for housing at least the light source and the light source substrate;
The backlight device according to any one of claims 1 to 9, wherein the mounting plate is configured using a side surface portion of the housing. The backlight device according to any one of claims 1 to 10, wherein a light emitting diode is used as the light source. A display device comprising the backlight device according to any one of claims 1 to 11. A television receiver comprising the display device according to claim 12.

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