JP2006058485A - Heat dissipator and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a cost of a backlight and to improve productivity thereof by relaxing accuracy of dimension and assembling of respective construction members and to efficiently dissipate heat produced from an LED. <P>SOLUTION: In the backlight unit of a liquid crystal display device, a heat dissipation sheet fitting recessed part 48 which has an opening dimension larger than an outside dimension of a heat dissipation sheet 44 and has a depth dimension less than a thickness dimension, is formed on a heat sink 37. When the backlight unit is attached to a back panel 13 in the state of having the heat dissipation sheet 44 fitted into the heat dissipation sheet fitting recessed part 48, the heat dissipation sheet 44 is crushed between the heat sink 37 and the back panel 13 toward a thickness direction and tightly attached to the back panel 13 and the heat sink 37. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention performs optical display by combining a backlight unit having a plurality of light emitting diodes on the back side of a transmissive display panel such as a liquid crystal panel and supplying illumination light emitted from each light emitting diode to the display panel. The present invention relates to a transmissive display device and a heat dissipation device that efficiently dissipates heat generated with the lighting operation of each light emitting diode.

  For example, LCD (Liquid Crystal Display) has a larger screen, lighter weight, thinner, lower power consumption, etc. compared to a cathode ray tube (CRT) display. For example, it is used for television receivers and various displays together with a self-luminous PDP display device (Plasma Display Panel). A liquid crystal display device encapsulates liquid crystal between two transparent substrates of various sizes, and changes the light transmittance by changing the direction of liquid crystal molecules by applying a voltage to optically display a predetermined image or the like. A liquid crystal panel is provided.

  Since the liquid crystal display device is not a light emitter, the liquid crystal display device includes a light source unit that supplies illumination light to the liquid crystal panel. As the light source section, a sidelight system that supplies illumination light from the side of the back surface to the liquid crystal panel and a backlight system that directly supplies illumination light from the back surface are generally employed. The backlight unit i includes, for example, a light source, a light guide plate that guides illumination light to the liquid crystal panel, a reflection sheet, a lens sheet, a diffusion sheet, and the like. Illumination light is supplied to the entire surface of the panel.

  In the backlight unit, a cold cathode fluorescent lamp (CCLF) in which, for example, mercury or xenon is enclosed in a fluorescent tube is used as a conventional light source. Such a backlight unit has problems of solving problems such as insufficient luminous brightness of a cold cathode fluorescent lamp, a relatively short life, or a low brightness region on the cathode side, and uniformity cannot be ensured. It was.

  By the way, in a large-sized liquid crystal display device, generally, a plurality of long cold cathode fluorescent lamps are arranged on the back of a diffusion plate for uniformizing illumination light emitted from a light source, and the illumination light is supplied to the liquid crystal panel. An area light type backlight (Area Litconfiguration Backlight) device is provided (for example, see Patent Document 1). Such area light type backlight devices are also required to solve the above-mentioned problems of the cold cathode fluorescent lamps. In particular, in large-sized television receivers exceeding 30 inches, higher brightness and higher uniformity are required. The problem has become more prominent.

  On the other hand, in the area light type backlight device, instead of the cold cathode fluorescent lamp described above as a light source, a large number of red, green and blue light emitting diodes (LEDs: hereinafter referred to as LEDs) are provided on the back side of the diffusion film. An LED area light type backlight that obtains white light by two-dimensionally arranging LEDs is drawing attention. Such an LED backlight device is designed to reduce the cost as the cost of the LED is reduced and to display a high-luminance image or the like on a large liquid crystal panel with low power consumption.

Japanese Patent Laid-Open No. 6-301034

  By the way, in the liquid crystal display device, a large amount of heat is generated from a large number of LEDs provided in the LED backlight device. In the liquid crystal display device, since the LED backlight device is combined with a sealed space portion on the back side of the liquid crystal panel, the heat generated from each LED described above is in a high temperature state over the sealed space portion. In a liquid crystal display device, the above-described optical plates are deformed or altered due to high temperatures, and illumination light is supplied to the liquid crystal panel in a non-uniform state to cause uneven color or streak-like lamp images. As a result, there is a problem that display accuracy is lowered. In addition, the liquid crystal display device has a problem that the operation becomes unstable due to the influence of heat on electronic components, integrated circuit elements, and the like due to high temperatures.

  Therefore, the liquid crystal display device includes a heat dissipation device that efficiently dissipates heat generated from each LED of the LED backlight device. It is also considered that the liquid crystal display device is adapted to dissipate the generated heat by blowing cooling air directly on each LED of the LED backlight device by a cooling fan, for example. However, such a heat radiating device is not practical because the cooling air strikes the optical plates and causes vibration and blurring.

  In the liquid crystal display device, a heat dissipating device that conducts heat generated from the sealed space where heat generated from each LED accumulates to a heat sink through an appropriate heat conducting member is considered. As is well known, a heat sink is made of, for example, a metal base having a large thermal conductivity, such as aluminum, and a plate-like base that is attached to a frame or the like, and a main surface facing the attachment surface of the base with a predetermined distance from each other. Thus, it is composed of a large number of fins standing up together. However, such a heat dissipating device cannot be directly disposed in the sealed space because the heat conducting member shields the illumination light, and can efficiently and uniformly dissipate the heat in the sealed space. In order to satisfy these conditions, there is a problem that the structure becomes complicated.

  In a liquid crystal display device, for example, a wiring board on which a large number of LEDs are mounted is attached to a heat radiating plate, the heat radiating plate is fixed to the back plate, and a heat sink is attached to the back side of the back plate to configure the heat radiating device. It is done. In such a heat radiating device, heat generated from each LED is transmitted to the heat sink using the heat radiating plate and the back plate as a heat conducting member to radiate heat. In the heat dissipating device, a cooling fan is further attached to the heat sink, and cooling air is blown between the fins, or air is exhausted from between the fins so that more efficient heat dissipation is performed.

  By the way, in a heat radiating device, in order to perform favorable heat conduction between a heat radiating plate, a back plate, and a heat sink, these members need to be coupled in close contact with each other. In the heat dissipating device, the heat dissipating plate and the back plate are formed in a flat plate shape, so that it is possible to perform relatively high-precision coupling. By combining these, better heat conduction can be performed.

  On the other hand, the heat sink is formed by extruding an aluminum material, and as described above, a base having a predetermined length that constitutes a fixed portion with respect to the back plate, and a plurality of fins erected integrally on the main surface of the base. Consists of In general, the heat sink is formed with a relatively thin base in order to reduce the thickness and increase the efficiency of heat conduction to each fin. High mechanical rigidity. The heat sink has a large thickness change in the width direction when the base is integrally provided with a large number of fins, and warpage due to processing accuracy and thermal expansion occurs. Therefore, it is difficult for the heat sink to adhere to the entire surface when the base is fixed to the back plate, and the heat conduction efficiency from the back plate is reduced due to the formation of a gap.

  In the heat radiating device, for example, it is possible to cope with fixing the heat sink to the back plate with a heat radiating sheet sandwiched between the base of the heat sink and the main surface of the back plate. However, the heat radiating device has a problem that even when such measures are taken, sufficient heat conduction cannot be performed due to a gap between the heat sink and the heat radiating sheet due to the above-described large warp of the heat sink. In addition, the heat dissipating device also has a problem that when the heat sink having warpage is fixed to the back plate with a set screw or the like, the amount of screwing of each set screw varies and cannot be firmly fixed.

  Therefore, the present invention relaxes the dimensional accuracy and assembly accuracy of each constituent member to reduce costs and improve productivity, and to efficiently dissipate heat generated from each light emitting diode. The purpose is to provide.

  The heat dissipating device according to the present invention that achieves the above-described object comprises a plurality of light-emitting unit bodies each having a plurality of light-emitting diodes mounted on a wiring board to form a plurality of light-emitting arrays. It is provided in a transmissive display device that is arranged on the back surface of the display panel and supplies illumination light emitted from each light emitting diode to the display panel. The heat dissipating device is formed of a metal material having high thermal conductivity characteristics, and is formed of a heat dissipating plate constituting the light emitting unit body by supporting each wiring board on the first main surface, and a metal material having high heat conductivity characteristics. A back panel on which a heat radiating plate is fixed on the first main surface opposite to the display panel and the second main surface is fixed, a heat sink formed of a metal material having high thermal conductivity, and a second main surface of the back panel And a heat dissipating sheet formed by an elastic material which is interposed between the back panel and the heat sink and forms a heat conduction path. The heat sink is composed of a base and a large number of fins standing upright with a predetermined distance from each other on the first main surface of the base, and the second main surface of the base is used as a mounting surface. 2 Attached to the main surface.

  In the heat dissipating device, a heat dissipating sheet fitting recess having an opening dimension larger than the outer dimension of the heat dissipating sheet and a depth dimension smaller than the thickness dimension is formed on the second main surface of the heat sink. In the heat radiating device, the heat radiating sheet is attached to the second main surface of the back panel with the heat radiating sheet fitted in the heat radiating sheet fitting recess. In the heat dissipating device, the heat dissipating sheet is crushed in the thickness direction between the heat sink and the back panel and is in close contact with the back panel and the heat sink.

  In the heat dissipating device, heat generated by the lighting operation of each light emitting diode is conducted to the back panel through the heat dissipating plate and further conducted from the back panel to the heat sink to radiate heat from each fin. In the heat radiating device, even if the base is warped, the heat sink is kept in close contact with the back panel via the heat radiating sheet, so that the light emission heat of each light emitting diode is efficiently radiated. Therefore, in the heat dissipating device, the transmissive display panel and the optical plates are set to a uniform temperature over almost the entire surface, thereby preventing the occurrence of color unevenness and the like and performing stable operation of each part.

  The display device according to the present invention that achieves the above-described object includes a transmissive display panel that performs optical display using illumination light supplied from the back side, a backlight unit, and a display panel and a backlight unit. Displayed on the first main surface, which is formed by a light conversion light guide unit that is arranged and supplies the display panel with a predetermined light conversion process and a uniform process for the illumination light, and a metal material having high thermal conductivity characteristics A heat dissipating plate is provided opposite to the panel, and includes a back panel attached by fixing the second main surface, a heat sink, and a heat dissipating sheet. In the display device, the backlight unit is formed of a large number of light-emitting diodes, a wiring board on which these light-emitting diodes are mounted, and a metal material having high thermal conductivity, and supports the wiring boards on the first main surface. A light emitting block body is constituted by the plate. The display device forms a plurality of light emitting arrays by arranging a plurality of light emitting block bodies on the back side of the display panel, and supplies illumination light emitted from each light emitting diode to the display panel.

  In the display device, the heat sink is formed of a metal material having high thermal conductivity characteristics, and includes a base and a large number of fins standing integrally with each other at a predetermined interval on the first main surface of the base. The second main surface of the base is attached to the second main surface of the back panel as a mounting surface, and heat generated by the lighting operation of each light emitting diode is conducted by the heat conducting means to dissipate heat from each fin. The display device is formed of an elastic material in which a heat dissipation sheet is interposed between the second main surface of the back panel and the second main surface of the heat sink, and is in close contact with the back panel and the heat sink to form a heat conduction path. Is done. In the display device, on the second main surface of the heat sink, a heat dissipating sheet fitting recess having an opening dimension larger than the outer dimension of the heat dissipating sheet and a depth dimension smaller than the thickness dimension is formed. In the display device, a heat radiating sheet is fitted into the heat radiating sheet fitting recess, and the heat radiating sheet is crushed in the thickness direction by attaching the heat sink to the back panel, and is closely attached to the back panel and the heat sink.

  In the display device, heat generated by the lighting operation of each light emitting diode is conducted to the back panel through the heat radiating plate, and further, heat is conducted from each fin by being conducted from the back panel to the heat sink. In the display device, even if the base is warped, the heat sink is kept in close contact with the back panel via the heat dissipation sheet, so that the light emission heat of each light emitting diode is efficiently radiated. Therefore, in the display device, the transmissive display panel and the optical plates are set to a uniform temperature over almost the entire surface, so that the occurrence of color unevenness and the like can be prevented and stable operation of each part can be performed.

  According to the present invention configured as described above, high-luminance optical display is performed by supplying a large amount of illumination light to a transmissive display panel from a light-emitting block body having a large number of light-emitting diodes as light sources. By being provided in the display panel, the generated heat, which is a large amount of heat generated by the lighting operation of each light emitting diode, is efficiently radiated. According to the present invention, a heat radiating plate that supports a wiring board on which each light emitting diode is mounted, a back panel to which the heat radiating plate is attached, a heat radiating sheet fixed to the back panel, and between the heat radiating sheet and the back panel By forming a heat conduction path that is kept in close contact with the heat dissipation sheet interposed between the two, efficient heat dissipation is performed, so that display with high brightness and high accuracy is performed.

  Hereinafter, a transmissive liquid crystal color display device (hereinafter abbreviated as a liquid crystal display device 1) 1 shown as an embodiment of the present invention will be described in detail with reference to the drawings. The liquid crystal display device 1 is used for a television receiver or a display monitor device having a large display screen of 40 inches or more, for example. As shown in FIGS. 1 and 2, the liquid crystal display device 1 includes a liquid crystal panel unit 2 and a backlight unit 3 that is combined with the back side of the liquid crystal panel unit 2 and emits large-capacity illumination light. Yes. The liquid crystal display device 1 performs an optical conversion process on the illumination light emitted from the backlight unit 3 between the liquid crystal panel unit 2 and the backlight unit 3 and supplies the illumination light to the liquid crystal panel unit 2. Unit 4, light guide unit 5 that supplies illumination light in a uniform state to liquid crystal panel unit 2, and reflection that reflects illumination light emitted toward the periphery from backlight unit 3 toward light guide unit 5 The part 6 and the heat radiating part 7 for radiating the heat generated in the backlight unit 3 are arranged.

  In the liquid crystal display device 1, a heat radiating portion 7 is combined with a first main surface 13a of a back panel 13 which will be described in detail later, and a number of later-described many provided on the backlight unit 3 on a second main surface 13b of the back panel 13. A pair of left and right heat sinks 37 that dissipate heat generated from the individual LEDs 18 are combined. In the liquid crystal display device 1, cooling fans 45 and 45 that promote the heat radiation action are attached to the heat sinks 37 and 37, respectively.

  In the liquid crystal display device 1, the liquid crystal panel unit 2 includes a liquid crystal panel 8 having a large display screen size of 30 inches or more. As shown in FIG. 9 and the holder frame member 10 are sandwiched and held via the spacer 11, the guide member 12, and the like. The liquid crystal display device 1 constitutes a so-called chassis member in which the holder frame member 10 and the back panel 13 assemble the constituent members, and is fixed to a mounting portion of a casing (not shown). The liquid crystal display device 1 is combined with a cover glass on the front side of the liquid crystal panel 8 (not shown).

  Although not described in detail, the liquid crystal panel 8 encloses a liquid crystal between the first glass substrate and the second glass substrate, which are held at a distance from each other by spacer beads, and applies a voltage to the liquid crystal. Change the light transmittance by changing the direction of the molecule. The liquid crystal panel 8 has a striped transparent electrode, an insulating film, and an alignment film formed on the inner surface of the first glass substrate. In the liquid crystal panel 8, a color filter of three primary colors, an overcoat layer, a striped transparent electrode, and an alignment film are formed on the inner surface of the second glass substrate.

  In the liquid crystal panel 8, a deflection film and a retardation film are bonded to the surfaces of the first glass substrate and the second glass substrate, respectively. In the liquid crystal panel 8, an alignment film made of polyimide is arranged in a horizontal direction with liquid crystal molecules as an interface, and the deflection film and the retardation film are achromatic and whitened to achieve full color using a color filter. The received image is displayed in color. The liquid crystal panel 8 is not limited to such a structure, and may of course be a liquid crystal panel having various configurations conventionally provided.

  The liquid crystal display device 1 is combined on the back side of the liquid crystal panel unit 2 described above to form a light guide space portion 14 in which the backlight unit 3 is optically sealed as shown in FIG. The backlight unit 3 includes a light emitting array 16 in which a predetermined number of light emitting unit bodies 15 are arranged on the same axis, and a plurality of light emitting arrays 16 are arranged in parallel with each other at a predetermined interval. As shown in detail in FIG. 3, the backlight unit 3 includes three light emitting unit bodies 15 arranged in the length direction to form one light emitting array 16, and the light emitting array 16 is arranged in six rows in the height direction. Configure side by side. The backlight unit 3 includes a total of 3 × 6 = 18 light emitting unit bodies 15.

  In the backlight unit 3, each light emitting unit body 15 includes a wiring board 17, a plurality of LEDs 18 mounted on the wiring board 17, an input connector 19, an output connector 20, and the like. In the backlight unit 3, a total of 25 LEDs 18, which are a combination of red LEDs, green LEDs, and blue LEDs, are mounted on the wiring board 17 of each light emitting unit body 15 so as to be positioned on the same axis. Therefore, the backlight unit 3 includes 25 × 3 = 75 LEDs for each light emitting array, and 75 × 6 = 450 LEDs 18 in total for 6 columns.

  As shown in FIGS. 2 and 5, each LED 18 holds the light emitting portion 18 a by a resin holder 18 b and pulls out a pair of terminals 18 c from the resin holder 18 b. Although not described in detail, each LED 18 is a so-called side emission type LED having directivity for emitting the main component of the emitted light in the outer peripheral direction of the light emitting portion 18a. In the backlight unit 3, the number of the light emitting unit bodies 15 and the number and interval of the LEDs 18 mounted on each of the light emitting unit bodies 15 are appropriately determined depending on the size of the liquid crystal panel 8, the light emission capability of each LED 18, and the like.

  In the light emitting unit 15, all the wiring boards 17 are formed with the same specifications, and although not shown, there are wiring patterns for connecting the LEDs 18 in series to the wiring boards 17, lands for connecting the terminals of the LEDs 18, and the like. Is formed. On each wiring board 17, an input connector 19 is mounted in the vicinity of one side in the width direction and on one side, and an output connector 20 is mounted on the other side.

  As shown in FIG. 3, each light emitting array 16 has the light emitting unit bodies 15 arranged in the same row with the wiring board 17 in the same direction. The light-emitting array 16 has an odd-numbered light-emitting array in the first, third, and fifth rows, and one edge portion on the side where each wiring board 17 is mounted with the input connector 19 and the output connector 20, respectively. The light emitting unit bodies 15 are arranged so that is directed downward. The light emitting array 16 has the second row, the fourth row, and the sixth row even-numbered row light-emitting arrays on the one side edge portion on the side where each wiring board 17 is mounted with the input connector 19 and the output connector 20, respectively. The light emitting unit bodies 15 are arranged so that is directed upward.

  Therefore, each light emitting array 16 is arranged in the same row so that each light emitting unit body 15 faces the input connector 19 and the output connector 20 of each adjacent wiring board 17. In addition, each light emitting array 16 is arranged in an odd number column and an even number column so that the input connector 19 and the output connector 20 of each wiring board 17 facing each light emitting unit body 15 face each other.

  In each light emitting array 16, each light emitting unit body 15 is connected in series by a lead wire with a connector (not shown) in the same column. As described above, each light emitting array body 15 is made to emit light by making the input connector 19 and the output connector 20 face each other. The shortest wiring is performed between the unit bodies 15. Each light emitting array 16 has an input connector 19 positioned on the right end side of the light emitting unit body 15 arranged on the right side in each odd-numbered row, and an output connector on the left end side of the light emitting unit body 15 arranged on the left side. 20 are located and arranged. Further, each light emitting array 16 has an output connector 20 positioned on the left end side of the light emitting unit bodies 15 arranged on the left side in the even-numbered columns, and inputs to the right end side of the light emitting unit bodies 15 arranged on the right side. Connector 19 is positioned and arranged. In each light emitting array 16, the lead wires are routed using the space in the length direction formed between the odd and even columns. The lead wires are drawn from each space and drawn to each space through a drawing opening (not shown) formed in the back panel 13 and are bundled by a clamper or the like in each space.

  As described above, the backlight unit 3 holds and guides the lead wires using the spaces formed between the light emitting arrays 16, thereby improving the space efficiency and simplifying the wiring process. In the backlight unit 3, the wrong combination of the light emitting unit bodies 15 is identified in the same row and between rows depending on the positions of the input connector 19 and the output connector 20 mounted on each wiring board 17. . In the backlight unit 3, each light emitting array 16 is designed to simplify the wiring structure between the wiring substrates 17, the wiring process, or to share the lead wires.

  In the liquid crystal display device 1, large-capacity illumination light based on the emitted light emitted from each LED 18 of the backlight unit 3 described above is supplied to the liquid crystal panel 8 via the optical conversion unit 4. The optical conversion unit 4 has an optical sheet laminate in which a plurality of optical sheets having an outer shape substantially equal to the outer shape of the liquid crystal panel 5 are stacked. The optical conversion unit 4 is an optical function sheet laminated body, an optical function sheet that omits details, but decomposes the illumination light supplied from the backlight unit 3 into orthogonal polarization components, compensates for the phase difference of the illumination light, and wide angle It consists of a plurality of optical function sheets having various optical functions, such as an optical function sheet for reducing the viewing angle and preventing coloring, or an optical function sheet for diffusing illumination light.

  As shown in FIG. 2, the optical conversion unit 4 is combined with the main surface of the diffusion light guide plate 21 of the light guide unit 5, which will be described later, as shown in FIG. 2, and via the holding bracket member 22 assembled to the back panel 13. Thus, the liquid crystal panel 5 is arranged on the back side with a predetermined facing distance. The optical conversion unit 4 is not limited to the above-described optical functional sheet laminate, and as other optical functional sheets, for example, a luminance improving film for improving luminance, a diffusion between upper and lower two sheets sandwiching a retardation film and a prism sheet. An optical function sheet such as a sheet may be provided.

  In the liquid crystal display device 1, the light conversion unit 4 guides the light in the light guide space 14 with the illumination light supplied from the backlight unit 3 having uniform luminance over the entire surface by the light guide unit 5. Is supplied to the liquid crystal panel 8. The light guide unit 5 includes a diffusion light guide plate 21 and a diffusion plate 23, and is disposed in the light guide space 14 while being held at a predetermined facing interval by an optical stud member 25 as will be described in detail later.

  The diffusion light guide plate 21 is made of a plate body that is substantially the same size and slightly thick as the liquid crystal panel 8 formed from a milky white synthetic resin material having a light guide property, such as an acrylic resin or a polycarbonate resin. The diffusion light guide plate 21 is combined with the optical function sheet laminate of the optical conversion unit 4 on one main surface, and the outer peripheral portion is held by the bracket member 22. The diffusion light guide plate 21 diffuses the illumination light incident from the other main surface by appropriately refracting and irregularly reflecting inside, and uniforming the luminance from the main surface side to the entire surface, thereby converting the optical conversion unit 4 is incident.

  The diffusion plate 22 is formed of a plate body having substantially the same size as the liquid crystal panel 8 formed of a transparent synthetic resin material such as acrylic resin, and is disposed to face the backlight unit 3 with a predetermined interval. By this, it has a function which controls the incident state of the emitted light radiate | emitted from each LED18. As shown in FIG. 2, dimming patterns 24 are formed on the diffusion plate 22 at portions facing the light emitting portions 18 a of the respective LEDs 18.

  Each light control pattern 24 is configured by printing a circular pattern having a slightly larger diameter than the light emitting portion 18a of the LED 18 with ink having light reflection / diffusion characteristics. Each dimming pattern 24 uses an ink prepared by mixing an ink material containing a light shielding agent and a diffusing agent at a predetermined ratio, and is precisely formed by, for example, a screen printing method or the like. For ink, as a light-shielding agent, for example, titanium oxide, barium sulfide, calcium carbonate, alumina oxide, zinc oxide, nickel oxide, calcium hydroxide, lithium sulfide, iron trioxide, methacrylic resin powder, mica (sericite), porcelain clay Powder, kaolin, bentonite, gold powder, pulp fiber or the like is used. In the ink, for example, silicon oxide, glass beads, glass fine powder, glass fiber, liquid silicon, crystal powder, gold plating resin beads, cholesteric liquid crystal liquid, recrystallized acrylic resin powder, and the like are used as a diffusing agent.

  The diffuser plate 22 reflects the component emitted directly upward from the emitted light emitted from the light emitting portion 18a of the LED 18 in which the respective dimming patterns 24 are arranged immediately below. The diffusing plate 22 makes the emitted light incident in a region where each light control pattern 24 is not formed, that is, a region not directly facing each light emitting array 16. In this way, the diffusion plate 22 regulates the emitted light that is emitted from each LED 18 and directly incident by each dimming pattern 24, thereby reducing the occurrence of a partial high-luminance region and making the luminance uniform. Light is supplied to the diffused light guide plate 21 from the entire surface.

  The diffusing plate 22 is composed of a large number of dots formed in each light control pattern 24 in a region having a larger diameter than the light emitting portion 18a of the LED 18, and transmits a part of the emitted light and reflects and diffuses a part thereof. By doing so, the amount of incident light may be limited. In this case, each of the light control patterns 24 is formed so that each light control pattern 24 has a dot density that is close to the peripheral portion, thereby restricting the amount of incident light at the central portion and shifting the position of the LED 18. You may comprise as what is called a gradation pattern to absorb. Since the diffusion plate 22 has a phenomenon that the illumination light is condensed in the region between the light emitting arrays 16 by using the side emission type LED 18 as described above, the dimming pattern 24 is formed in a vertically long shape. You may make it suppress generation | occurrence | production of this.

  In the liquid crystal display device 1, a part of the emitted light emitted from each LED 18 and incident on the diffusion plate 23 beyond the critical angle is reflected on the surface of the diffusion plate 23. In the liquid crystal display device 1, the outgoing light emitted from each LED 18 of the backlight unit 3 to the surroundings, the outgoing light reflected by the surface of the diffusion plate 23, or the outgoing light reflected by each dimming pattern 24 is reflected. The light is reflected by the portion 6 and efficiently supplied to the light guide portion 5 through the diffusion plate 23. In the liquid crystal display device 1, the reflection portion 6 is repeatedly reflected between the diffuser plate 23 and the reflectance is improved by the principle of increased reflection.

  As shown in FIGS. 2 and 4, the reflection unit 6 includes a single large reflection plate 26 and a large number of reflection sheet pieces 27 provided for each light emitting unit body 15. The reflection portion 6 is positioned by a heat radiating plate 28 and an optical stud member 25 constituting the heat radiating portion 7 and combined with the backlight unit 3 as will be described in detail later. The sheet piece 27 is held.

  The reflection plate 26 is a large-sized member having a relatively high surface accuracy with no distortion and substantially the same shape as the liquid crystal panel 8 that is combined with the light guide unit 5 while being opposed to each other. Of mechanical rigidity is required. Therefore, the reflecting plate 26 is formed by joining, for example, a reflecting material 30 made of foaming PET or the like containing a fluorescent agent on the surface of an aluminum plate 29 as a base material. The reflection plate 26 may be made of not only an aluminum material but also a stainless steel plate having a mirror surface. Further, when the reflective plate 26 is a relatively small-sized liquid crystal display device, the reflective plate 26 may be formed of, for example, foaming PET containing a fluorescent agent. Foamable PET is lightweight, has a high reflectivity characteristic of about 95%, and has features such as scratches on the reflecting surface having a color tone different from that of the metallic luster color, and the conventional liquid crystal display device. It is also used.

  As shown in FIG. 3, six rows of guide openings 31 are formed in the reflection plate 26 so as to correspond to the respective light emitting arrays 16. In detail, each guide opening 31 is located on the same axis and is divided into a plurality of horizontally long unit guide openings 32 a to 32 n (collectively referred to as unit guide openings 32) divided by bridge portions 33. Composed. Each unit guide opening 32 has a width that is slightly larger than the outer diameter of the light emitting portion 18a of the LED 18, and is formed with a length sufficient to allow each of the five LEDs 18 to pass therethrough.

  Therefore, since the guide opening 31 has 75 LEDs 18 in each light emitting array 16, it is constituted by 75 ÷ 5 = 15 unit guide openings 32 for each column. The guide opening 31 is not limited to such a configuration, and may be configured by one opening having a length corresponding to the entire length of each light emitting array 16. However, the guide openings 31 pass through several LEDs 18 because each bridge portion 33 holds the mechanical rigidity of the reflection plate 26 and also functions as a portion for holding the reflection sheet piece 27 as will be described later. It is preferable that the gaps are formed with a certain interval.

  For the reflection sheet piece 27, a member having high reflection characteristics such as the above-described foaming PET material is used. The reflection sheet piece 27 is substantially the same length as each wiring board 17 and has a slightly larger width and is slightly larger than the width of the heat radiating plate 28. It is formed in a rectangular piece having a small width. In the reflection sheet piece 27, 25 guide holes 34 are formed corresponding to the 25 LEDs 18 provided on the light emitting unit bodies 15 on the same axis. Each guide hole 34 is formed on the reflective sheet piece 27 on the same axis line and aligned in the length direction, and each of the guide holes 34 is a circular hole having an inner diameter substantially equal to that of the light emitting portion 18 a of each LED 18.

  For each light emitting unit body 15, the reflection sheet piece 27 is combined with the wiring substrate 17 that is supported by the heat radiating plate 28 through the light emitting portions 18 a of the LEDs 18 that are opposed from the respective guide holes 34. The reflection sheet piece 27 is formed in a size corresponding to each light emitting unit body 15 and can be accurately positioned with each LED 18 facing from each guide hole 34 by being directly combined with the wiring board 17. It is. Therefore, the reflection sheet piece 27 is protruded from each guide hole 34 in a state where the outer peripheral portion of the light emitting portion 18a of each LED 18 is in close contact with the inner peripheral wall thereof. The reflection sheet piece 27 is formed to have a width substantially the same as or slightly smaller than a board fitting recess 38 of the heat radiating plate 28 described later, and the opening edge of each guide hole 34 is locked on the upper surface of the resin holder 18b of the LED 18. You may do it.

  As shown in FIGS. 3 and 5, the reflector 6 penetrates the light emitting part 18 a of each LED 18 facing the respective light emitting unit bodies 15 through the reflecting sheet pieces 27 from the respective guide holes 34 to the wiring board 17. Combined. The reflection part 6 is fixed on each heat radiating plate 28 so that the reflection plate 26 is overlapped on each reflection sheet piece 27 and the details will be described later. In the reflecting portion 6, a predetermined number of guide holes 34 on the reflecting sheet piece 27 side are caused to face each guide opening 31 of the reflecting plate 26, so that the light emitting portion 18 a of the LED 18 is penetrated from each guide opening 31. It faces the diffusion plate 23.

  In the reflection portion 6, as described above, each reflection sheet piece 27 is formed of an insulating foamable PET material, and the reflection plate 26 is formed of a laminate of an aluminum plate 29 and a foamable PET material 30. In the reflection part 6, as shown in FIG. 5, each reflection sheet piece 27 made of an insulating material has a small diameter relative to the inner peripheral edge of each guide opening 31 of the reflection plate 26 from which the aluminum material is exposed. The inner peripheral edge of each guide hole 34 protrudes inward over the entire periphery and is combined. Therefore, in the reflection portion 6, electrical insulation between the aluminum portion of the reflection plate 26 and the terminal 18 c of each LED 18 is maintained by each reflection sheet piece 27.

  In the reflection part 6, the reflection plate 26 is assembled after the reflection sheet pieces 27 are combined for each light emitting unit body 15 as described above. In the reflection part 6, each reflection sheet piece 27 is held by pressing the reflection sheet piece 27 onto the heat dissipation plate 28 by fixing the reflection plate 26 on the heat dissipation plate 28. In the reflecting portion 6, as described above, the reflecting plate 26 divides the unit guide opening portions 32 through which the five LEDs 18 protrude through the bridge portions 33 to form the guide opening portions 31. Therefore, in the reflection part 6, each bridge | bridging part 33 hold | maintains these reflection sheet pieces 27 still more reliably by pressing each reflection sheet piece 27 at predetermined intervals with respect to the length direction. The reflecting portion 6 does not require a structure for preventing the reflection sheet piece 27 from being lifted or oscillating, but the structure and the assembly can be simplified by such a configuration.

  By the way, as described above, the reflection plate 6 has the reflection plate 26 having a large size equivalent to that of the liquid crystal panel 8, and the support portion 13a and the optical stud member 25 formed on the back panel 13 as shown in FIG. And is combined with the backlight unit 3. When the reflection plate 26 is configured by a circular hole that penetrates each LED 18 one by one, like the reflection sheet piece 27, the reflection plate 26 is extremely difficult to position the circular hole and the LED 18. Become. The reflection portion 6 forms the reflection plate 26 with high dimensional accuracy, and requires the correspondence of positioning and assembling each member with high accuracy, thereby greatly increasing costs from high-precision component manufacturing and assembly processes. As a result, the reflection plate 26 is distorted by the heat change.

  The reflection part 6 is configured by combining the reflection plate 26 and a large number of reflection sheet pieces 27, thereby preventing a gap from being generated in the outer peripheral part of each LED 18. The reflection unit 6 can prevent a part of the emitted light emitted from each LED 18 from leaking to the back side from the gap of the outer peripheral portion, and can improve the light efficiency and perform high luminance display. To do. The reflection unit 6 can simplify the structure by eliminating the need for a structure that shields leaked light from the back side.

  In the reflecting portion 6, as described above, the reflecting plate 26 and the multiple reflecting sheet pieces 27 are combined to form the guide hole 34 formed in each reflecting sheet piece 27 with the light emitting portion 18a of each LED 18 and precisely. In close contact with the outer periphery. Therefore, in the reflection part 6, the emitted light radiate | emitted from each LED18 is prevented from leaking to the back side from the clearance gap between the inner peripheral wall of the guide hole 34, and the outer peripheral part of the light emission part 18a.

  In the reflection part 6, the reflective sheet piece 27 is formed in a size that is combined for each light emitting unit body 15, but in a size that combines two or three according to the size of the light emitting unit body 15. You may form, and you may form in the magnitude | size combined across several light emission unit bodies 15. FIG. However, when the reflecting sheet piece 27 is too large, it is difficult to accurately align the guide holes 34 and the LEDs 18, and the effect of the laminated structure described above cannot be achieved. Formed.

  In the liquid crystal display device 1, a large number of optical stud members 25 are attached to the back panel 13, and the optical function sheet body that constitutes the optical conversion unit 4 described above via the optical stud members 25, and the light guide unit 5. The diffusing light guide plate 21 and the diffusing plate 23 constituting the reflector and the reflecting plate 26 constituting the reflecting portion 6 are positioned with respect to each other and the parallelism between the opposing principal surfaces is accurately maintained over the entire surface. Has been. In the liquid crystal display device 1, color unevenness and the like are prevented by maintaining the distance and parallelism between the large-sized plates.

  In the liquid crystal display device 1, for the combination with the optical stud member 25, a large number of fitting holes 23 a are formed in the diffusion plate 23 described above, and a large number of fitting holes 26 a are formed in the reflection plate 26. Is done. The fitting holes 23a and 26a are formed between the rows of the light emitting arrays 16 and the axes thereof being aligned in a state where the diffusion plate 23 and the reflection plate 26 are combined.

  Each optical stud member 25 is a member formed integrally with a milky white synthetic resin material having light guiding properties, mechanical rigidity, and a certain degree of elasticity, such as a polycarbonate resin, and is formed on the back panel 13 as shown in FIG. Each is attached to an integrally formed attachment portion 35. The back panel 13 is formed with a large number of attachment portions 35 that are formed integrally with a substantially trapezoidal convex portion on the inner surface side. As for the attachment part 35, the upper surface comprises the mounting surface of the diffusion plate 23, and the attachment hole 35c is each penetrated and provided. The attachment portion 35 is formed so as to be positioned between the rows of the light emitting arrays 16 in a state where the backlight unit 3 described above is combined with the back panel 13.

  As shown in FIG. 2, each optical stud member 25 has a shaft-like base portion 25a, a fitting portion 25b formed at the tip of the shaft-like base portion 25a, and a predetermined distance from the fitting portion 25b. A flange-shaped first receiving plate portion 25c integrally formed around the circumference of the shaft-shaped base portion 25a, and a single piece around the circumference of the shaft-shaped base portion 25a with a predetermined interval from the first receiving plate portion 25c. And a flange-like second receiving plate portion 27d formed in the above. Each optical stud member 25 has an axial base portion 25a formed with an axial length that defines the facing distance between the attachment portion 35 of the back panel 13 and the diffusion light guide plate 21, and is provided with a predetermined length from the second receiving plate portion 27d. A step portion 27e is formed at the height position.

  Each optical stud member 25 has a long-axis cone in which the shaft-like base portion 25a has a slightly larger diameter than the fitting hole 23a in which the step portion 25e is formed in the diffusing plate 23 and has a gradually smaller diameter toward the distal end portion 25g. It is formed with a shape. Each optical stud member 25 is formed with an axial stealing hole 25f in the axial base portion 25a located slightly above the stepped portion 25e. Each optical stud member 25 has a meat stealing hole 25f formed in the shaft-like base portion 25a in a range where the outer diameter is larger than the fitting hole 23a of the diffusion plate 23, thereby converging at this portion. Add habits.

  Each optical stud member 25 is formed with an interval in which the first receiving plate portion 25 c and the second receiving plate portion 25 d maintain the facing distance between the diffusion plate 23 and the reflection plate 26. Each optical stud member 25 has a shaft-like base portion 25a formed with the first receiving plate portion 25c and the second receiving plate portion 25d at substantially the same diameter as the fitting hole 23a of the diffusion plate 23. Each optical stud member 25 has a fitting portion 25b having an outer diameter that is substantially equal to the outer diameter of the mounting hole 35a formed in the mounting portion 35 on the back panel 13 side, and this mounting hole in the axial direction. The cross section gradually becoming larger than the inner diameter of 35a has a substantially truncated cone shape. Each optical stud member 25 is given converging habits when the fitting portion 25b forms a slit (not shown) from the large-diameter portion toward the distal end side.

  Each optical stud member 25 is formed such that the distance between the large diameter portion of the fitting portion 25 a and the first receiving plate portion 25 c is substantially equal to the sum of the thickness of the back panel 13 and the thickness of the diffusion plate 23. Each optical stud member 25 has a first receiving plate portion 25c slightly larger in diameter than the inner diameter of the fitting hole 23a of the diffusion plate 23, and a second receiving plate portion 25d of the fitting hole 26a of the reflecting plate 26. The diameter is slightly larger than the inner diameter.

  In the liquid crystal display device 1, the reflection plate 26 is mounted on the mounting portion 35 of the back panel 13 with respect to the mounting hole 35 a facing the back panel 13 in a state where the heat radiating unit 7 and the backlight unit 3 are assembled with the back panel 13. The fitting holes 26a are combined to face each other. In the liquid crystal display device 1, the optical stud members 25 are assembled to the attachment portions 35 from the inner surface side of the back panel 13 in this state. In each optical stud member 25, the fitting portion 25 b is pushed into the attachment hole 35 a of the attachment portion 35 through the fitting hole 26 a of the reflection plate 26. Each optical stud member 25 is constricted by the action of slitting when the fitting portion 25b passes through the attachment hole 35a, and is returned to the natural state after passing through, thereby being prevented from coming off on the attachment portion 35. It is assembled in a standing state.

  In the liquid crystal display device 1, each optical stud member 25 sandwiches the attachment portion 35 and the reflection plate 26 in the thickness direction between the fitting portion 25 b and the first receiving plate portion 25 c, so that the back panel 13 is supported. The reflecting plate 26 is held in a positioned state. In the liquid crystal display device 1, the reflection plate 26 is precisely positioned and holds each reflection sheet piece 27. In this state, each optical stud member 25 is erected on the attachment portion 35 of the back panel 13 with the upper portion protruding from the reflection plate 26 from the first receiving plate portion 25c of the shaft-like base portion 25a.

  In the liquid crystal display device 1, the diffusion plate 23 is combined with each optical stud member 25 by inserting and fitting the respective fitting holes 23 a from the opposing tip end 25 g side. Each of the optical stud members 25 is allowed to move over the stepped portion 25e of the diffusion plate 23 that is pushed in the axial direction by causing the large-diameter portion to converge by the action of the meat stealing hole 17f. In each optical stud member 25, when the diffusion plate 23 gets over the step portion 25e and hits the second receiving plate portion 25d, the large diameter portion returns to the natural state, and the step portion 25e and the second receiving plate portion 25d The diffusion plate 23 is sandwiched in the thickness direction.

  In the liquid crystal display device 1, as shown in FIG. 2, each optical stud member 25 projects an upper portion from the second receiving plate portion 25 d of the shaft-like base portion 25 a from the diffusion plate 23. In the liquid crystal display device 1, the diffusion light guide plate 21 in which the optical function sheet laminate of the optical conversion unit 4 is superimposed on the tip end portion 25 h of each optical stud member 25 is made to abut on the bottom side thereof. Assembled.

  In the liquid crystal display device 1, each optical stud member 25 is assembled on the attachment portion 35 of the back panel 13 by a simple method of pushing the fitting portion 25b into the attachment hole 35a. In the liquid crystal display device 1, the diffusion plate 23 and the reflection plate 26 are positioned by each optical stud member 25, and the facing distance between the diffusion plate 23, the reflection plate 26, the diffusion light guide plate 21, and the optical conversion unit 4. Is held precisely. In the liquid crystal display device 1, by providing the above-described many optical stud members 25, a complicated positioning structure and interval holding structure are not necessary, and the assembly process can be simplified.

  Each optical stud member 25 can be used interchangeably with liquid crystal panels 8 of various sizes, and parts can be shared. The optical stud member 25 is not limited to the structure described above, and the specific structure of each part is appropriately changed based on the configuration of the liquid crystal display device 1. The optical stud member 25 is attached by being pushed into the attachment hole 35a of the back panel 13 by, for example, being provided with a converging habit by forming a slit in the fitting portion 25b. The convex portion may be formed integrally, and after fitting into the mounting hole 35a having the key groove formed on the inner peripheral portion, it may be rotated to be prevented from coming off.

  In the liquid crystal display device 1, the above-described plates are precisely positioned by the optical stud member 25, so that the illumination light is converted into the light guide space 14 formed between the liquid crystal panel 8 and the backlight unit 3. On the other hand, operations such as light guide, diffusion, and reflection are performed in a stable state. Therefore, in the liquid crystal display device 1, the occurrence of uneven color in the liquid crystal panel 5 is prevented. Since the optical stud member 25 is made of milky white light-guiding synthetic resin material as described above, the illumination light incident on the inside from the outer peripheral surface is diffused so that the tip 25h is not partially brilliant. By doing so, the illumination light is uniformly incident on the diffusion light guide plate 21 from the light guide space portion 14.

  In the liquid crystal display device 1, specifically, as shown in FIG. 3, the above-described optical stud members 25 are located between the light emitting arrays 16 with respect to the back panel 13, and five in the horizontal direction and three in the vertical direction. A total of 15 pieces are attached. In the liquid crystal display device 1, the diffusion plate 23 on which the light control pattern 24 is formed and the reflection plate 26 in which the aluminum plate 29 and the foamable PET material 30 are joined have front and back characteristics, and must be combined without mistake. .

  As described above, the diffusing plate 23 and the reflecting plate 26 have fitting holes 23 a and 26 a through which the shaft-like base portion 25 a of the optical stud member 25 penetrates in the lateral direction corresponding to the mounting positions of the optical stud members 25. 15 in total, 3 in the vertical direction. In the liquid crystal display device 1, as shown in FIG. 3, the second optical stud member 25 </ b> A from the left side of the lower row is erected on the back panel 13 at a position different from each optical stud member 25 on the upper row side. To. In the liquid crystal display device 1, the second fitting holes 23 a and 26 a from the left side of the lower row relative to the optical stud member 25 </ b> A are connected to the diffusion plate 23 and the reflection plate 26, respectively. 26a is formed at a different position.

  Therefore, in the liquid crystal display device 1, even if the diffusion plate 23 and the reflection plate 26 are combined with the front and back being mistaken, they are combined because the fitting holes 23 a and 26 a do not exist at the position facing the optical stud member 25 A. I can't. In the liquid crystal display device 1, an erroneous combination prevention structure of the diffusion plate 23 and the reflection plate 26 is configured by such a structure. In the liquid crystal display device 1, the optical stud member 25 </ b> A, the diffusion plate 23, and the fitting holes 23 a and 26 a of the reflection plate 26 constituting the erroneous combination prevention structure may be provided at any position other than the center position. Are combined in a stable state, it is better to be provided at the inner position than at the outer peripheral position, and they may be provided at a plurality of places instead of one place.

  The back panel 13 is formed into a member having a size slightly larger than the outer shape of the liquid crystal panel 8 by using, for example, an aluminum material that is relatively light and has mechanical rigidity. The back panel 13 constitutes a chassis member to which the constituent members are attached as described above, and has a large thermal conductivity characteristic by itself, thereby radiating heat generated from the light guide space portion 14 and circuit components. Have. Further, as will be described later, the back panel 13 is interposed between a heat radiating plate 28 and a heat sink 37 constituting the heat radiating portion 7, and serves as a heat conduction member that efficiently conducts heat from the heat radiating plate 28 to the heat sink 37. Also works.

  As described above, the back panel 13 is formed with the outer peripheral wall portion that combines the front frame member 9 and the holder member 10 at the outer peripheral portion, the mounting portion 35 for attaching the optical stud member 25, and the heat dissipation plate 28 that omits details. An attachment portion for attaching the lead wire or a lead-out opening and a crossing portion for drawing out the lead wire are formed. Although not shown, the back panel 13 is formed with a large number of attachment portions and attachment holes for fixing to the housing.

  As described above, the back panel 13 has the heat dissipation plate 28 attached to the first main surface 13a on the inner surface side, and the heat sink 42, the control circuit unit, and the like attached to the second main surface 13b on the outer surface side. Although the back panel 13 is formed as a member having mechanical rigidity with an aluminum material as described above, the thickness and weight of the liquid crystal display device 1 are increased by increasing the thickness. When the back panel 13 is thin, when the heat radiating plate 28 is firmly screwed, the mounting portion is deformed, and the above-described optical plate members are bent. As will be described later, the back panel 13 uses a relatively large heat dissipation plate 28 and a heat sink 37 to maintain the mechanical rigidity and reduce the thickness.

  In the liquid crystal display device 1, a large number of LEDs 18 are provided in the backlight unit 3, and a high-capacity display is provided by supplying large-capacity illumination light to the liquid crystal panel unit 2 by the emitted light emitted from the LEDs 18. To be done. In the liquid crystal display device 1, the heat generated from each LED 18 is hot inside the light guide space 14 that is sealed between the liquid crystal panel unit 2 and the backlight unit 3 and sealed around the periphery. In the liquid crystal display device 1, the characteristics of each optical function sheet of the optical conversion unit 4 described above change due to high temperature, the lighting state of each LED 18 becomes unstable, and color unevenness occurs in the liquid crystal panel 8. In addition, the operation of the electronic components constituting the circuit unit is made unstable, or a large dimensional change is caused in each constituent member.

  The liquid crystal display device 1 is configured to perform a stable operation by efficiently radiating the heat generated from each LED 18 by the heat radiating unit 7. The heat radiating section 7 includes a heat radiating plate 28 that also serves as a mounting member for each light emitting unit body 15 described above, a heat pipe 36 that is combined with the heat radiating plate 28, and an end portion of the heat pipe 36 that receives heat conduction. The heat sinks 37 and 37 are arranged on the back side of the heat sink 37 or cooling fans 45 and 45 for promoting the cooling function of the heat sinks 37.

  Each heat radiation plate 28 is provided for each of the light emitting arrays 16 in six rows. The light emitting array 16 is made of, for example, an aluminum material having excellent thermal conductivity, good workability, light weight, and low price. It is formed in the shape of a long rectangular plate substantially equal to the length and width. Each heat dissipating plate 28 serves as an attachment member to which three light emitting unit bodies 15 are attached, and is formed with a predetermined thickness having mechanical rigidity. In addition, about each heat radiating plate 28, it is not limited to an aluminum material, You may make it form with favorable heat conductivity, for example, an aluminum alloy material, a magnesium alloy material, a silver alloy material, a copper material, etc. Each heat dissipation plate 28 may be formed by an appropriate processing method such as pressing or cutting when the liquid crystal display device 1 is relatively small.

  As shown in FIG. 5, the three wiring boards 17 constituting the light emitting block 15 are attached to each heat radiation plate 28 with the first main surface 28 a as an attachment surface, with their end faces in the lengthwise direction abutting each other. It is done. Each heat radiating plate 28 is formed with a board fitting recess 38 that is fitted to the first main surface 28a and into which the wiring board 17 is fitted. Each heat dissipating plate 28 is formed so that the board fitting recess 38 is substantially the same width as the wiring board 17 and has a height slightly larger than the thickness thereof, and the bottom face and the width of the fitted wiring board 17. Hold both sides of the direction. Each heat dissipating plate 28 fixes the wiring board 17 fitted in the board fitting recess 38 with a plurality of mounting screws 39.

  Each of the heat radiating plates 28 is formed with a receiving convex portion 38a in the length direction in which the bottom surface of the wiring board 17 is in close contact with each other by leaving the central region in the width direction as a convex portion having a predetermined width in the substrate fitting concave portion 38. At the same time, meat stealing recesses 38b and 38c are formed over the entire length in the length direction along both sides of the receiving projection 38a. As shown in FIG. 5, each heat dissipation plate 28 is formed with a width corresponding to the LED mounting area on which each LED 18 of the wiring board 17 is mounted, as shown in FIG. Heat is efficiently transmitted from the LED mounting region that is heated so that heat is dissipated. In addition, although each heat sink plate 28 formed the meat stealing recessed part 38b, 38c in order to maintain weight reduction and dimensional accuracy, these meat stealing recessed parts 38b, 38c may also be configured as a heat pipe fitting part. .

  Each of the heat radiating plates 28 is integrally formed with reflecting plate receiving portions 40, 40 along the both sides of the opening edge of the board fitting recess 38 over the entire length direction. The reflection plate receiving portions 40, 40 are each formed of a plate-like portion protruding in the width direction from the opening edge of the board fitting recess 38 of the heat radiating plate 28, and as a whole, as shown in FIG. The surface 28 a is set to be larger than the width of the reflection sheet piece 27. The reflection plate receiving portions 40, 40 engage the side edges of the reflection sheet piece 27 combined with the light emitting unit body 15 by projecting the light emitting portions 18 a of the LEDs 18 from the respective guide holes 34.

  The reflection plate receiving portions 40 and 40 support both sides of the reflection sheet piece 27 when the reflection sheet piece 27 is formed with a width larger than the opening width of the board fitting recess 38. The reflection plate receiving portions 40, 40 are formed so as to hold the reflection sheet piece 27 combined in this case at a height position where the light emitting portion 18a of each LED 18 protrudes from the corresponding guide hole 34.

  In the heat radiating portion 7, six heat radiating plates 28 are attached to the inner surface of the back panel 13 at a predetermined interval. Each heat radiating plate 28 has three light emitting unit bodies 15 formed by mounting a predetermined number of LEDs 18 on the wiring board 17 in a board fitting recess 38, and constitutes a mounting member for six rows of light emitting arrays 16. To do. In the heat dissipating part 7, the reflecting plate 26 constituting the reflecting part 6 is assembled so as to cover each heat dissipating plate 28 in a state where the reflecting sheet piece 27 is assembled to each light emitting unit body 15.

  The inner surface of the reflection plate 26 is pressed against each of the heat radiating plates 28 on the respective reflection plate receiving portions 40, 40. Double-sided adhesive tapes 41 and 41 are bonded to the heat radiating plates 28 over the entire length of the reflection plate receiving portions 40 and 40 in advance, and the inner surface of the pressed reflection plate 26 is bonded and fixed. The reflection plate 26 supports the outer peripheral portion on the support portion 13 a formed on the back panel 13 as described above, and is held by the optical stud member 25 in the region between the light emitting arrays 16, and further configures each light emitting array 16. Also in the region of the heat radiating plate 28 to be held, it is held by the reflection plate receiving portions 40 and 40. The reflection plate 26 is positioned with high accuracy by such a structure and combined with no distortion or the like.

  In the liquid crystal display device 1, each heat radiating plate 28 constituting the heat radiating portion 7 functions as an attaching member for the light emitting unit body 15 of the backlight unit 3, and also functions as an attaching member for the reflecting plate 26 constituting the reflecting portion 6. To do. In the liquid crystal display device 1, the large-sized reflection plate 26 is precisely positioned and held by a structure that also functions, thereby improving the light efficiency and preventing the occurrence of color unevenness. In the liquid crystal display device 1, the reflection plate 26 is combined with each heat radiation plate 28 by an extremely simple operation. In the liquid crystal display device 1, the reflection plate 26 is bonded by the double-sided adhesive tapes 41, 41 bonded on the reflection plate receiving portions 40, 40 of each heat radiation plate 28, but for example, the reflection plate receiving portion 40, The reflective plate 26 may be fixed by an adhesive applied on the plate 40.

  In the liquid crystal display device 1, as described above, the board fitting recess 38 is formed on the main surface of the heat radiating plate 28 over the entire length direction, and the wiring of each light emitting unit body 15 is provided in the board fitting recess 38. The substrate 17 is assembled. In the liquid crystal display device 1, the substrate fitting recess 38 is closed by joining the reflection plate 26 on the reflection plate receiving portion 40. In the liquid crystal display device 1, the LEDs 18 protrude from the guide holes 34 formed in the reflection sheet piece 27 with the outer peripheral portions thereof being in close contact with each other as described above. Therefore, in the liquid crystal display device 1, each heat dissipating plate 28 has a substrate-enclosed recess 38 as a substantially hermetic structure on the main surface side to ensure dust resistance.

  As described above, the liquid crystal display device 1 has a structure in which the substrate fitting recess 38 is formed over the entire area in the length direction with respect to the heat radiating plate 28 and thus is open to the side surface. In the liquid crystal display device 1, as shown in FIG. 4, a dustproof member 43 formed of, for example, a foamed urethane resin or a sponge material is joined on the reflection plate receiving portion 40 at the side portion of the heat radiating plate 28. In the liquid crystal display device 1, the dustproof member 43 closes the side opening portion of the substrate fitting recess 38, so that dust and the like can be prevented from entering the substrate fitting recess 38 and the dustproofness can be improved. To.

  Each heat dissipating plate 28 constitutes a heat pipe fitting recess 42 in which the heat pipe 36 is fitted on the second main surface 28b facing the first main surface 28a, and a mounting portion with the back panel 13 (not shown). A plurality of mounting studs and positioning dowels are integrally formed. The heat pipe fitting recess 42 is a cross-section that is located at a substantially central portion in the width direction and opens over the entire length direction on the second main surface 28b facing the receiving projection 38a on the first main surface 28a side. Consists of a substantially arch-shaped groove. The heat pipe fitting concave portion 42 has an opening width substantially equal to the outer diameter of the heat pipe 36, and caulking convex edges 42a and 42b are integrally formed at the opening portion.

  A heat pipe 36 is assembled in each heat pipe fitting recess 42 in each heat radiation plate 28. Each heat pipe 36 is assembled into the inside from the opening of the heat pipe fitting recess 42 and, as shown in FIG. 5, caulking processing is performed so as to close the opening against the caulking convex edges 42a and 42b. Thus, the outer peripheral portion is assembled in a state of being in close contact with the inner wall of the heat pipe fitting recess 42. Each heat pipe 36 is assembled over the entire length of the heat radiating plate 28 at a portion facing the mounting region of the LED 18 so that efficient heat radiation is performed.

  In the heat radiating portion 7, the heat pipes 36 are combined in the heat pipe fitting recesses 42 formed in the heat radiating plates 28, so that the heat radiating plates 28 also serve as holding members for the heat pipes 36. In the heat radiating portion 7, the mounting structure of the heat pipe 36 is simplified, the handling of the precise heat pipe 25 is simplified at the time of assembly and the like, and the occurrence of bending or breakage is prevented. In the heat radiating section 7, each heat radiating plate 28 is combined with the light emitting unit body 15 and the heat pipe 28 positioned and close to each other. An efficient heat conduction path is formed between them.

  In addition, in the heat radiating part 7, the heat pipe fitting recess 38 opened in the second main surface 28b of each heat radiating plate 28 is formed and the heat pipe 36 is assembled, but the structure is not limited to this. . In each heat radiating plate 28, a heat pipe fitting hole opened at at least one end in the longitudinal direction may be formed, and the heat pipe 36 may be assembled inside from the side surface direction.

  The heat pipe 36 is a member generally employed for conducting heat from a high-temperature power supply unit or the like to various heat dissipating means in various electronic devices, and is a metal pipe such as copper having excellent heat conductivity. It is configured by enclosing a conductive medium such as water that is vaporized at a predetermined temperature in a state where the inside of the material is exhausted, and has a highly efficient heat conduction capability. As described above, the heat pipe 36 is integrally assembled with each heat radiating plate 28, and both ends thereof are connected to the heat sink 37. In the heat pipe 36, the conductive medium enclosed inside receives heat conduction from the high-temperature side heat radiating plate 28 and vaporizes from liquid to gas. In the heat pipe 36, the vaporized conductive medium flows through the pipe to the connection portion with the low-temperature heat sink 37 and is cooled, thereby releasing condensation heat and liquefying. In the heat pipe 36, the liquefied conductive medium moves to the heat radiating plate 28 side by a capillary phenomenon in a plurality of longitudinal grooves or porous layers formed on the inner wall of the metal pipe, and circulates in the pipe. As a result, it has a highly efficient heat conduction effect.

  In the heat radiating portion 7, each heat radiating plate 28 is combined with each light emitting unit body 15 in the board fitting concave portion 38 and the heat pipe 36 is assembled in the heat pipe fitting concave portion 42 with respect to the back panel 13. Precisely positioned and fixed. In the heat radiating portion 7, each heat radiating plate 28 extends substantially over the entire length direction with a predetermined interval in the width direction on the first main surface 13 a of the back panel 13 as shown in FIG. 3. Thus, the above-described light emitting array 16 is configured.

  In the heat radiating portion 7, as shown in FIG. 3, heat sinks 37 and 37, the details of which will be described later, are located on the second main surface 13b side of the back panel 13 and are located on both sides in the longitudinal direction and arranged in the height direction. Has been. In the heat radiating portion 7, the heat radiating plates 28 on both sides constituting each light emitting array 16 are extended so as to be orthogonal to the respective heat sinks 37 via the back panel 13. In the heat radiating portion 7, the heat radiating plates 28 and the heat sinks 37 are fastened together by mounting screws 52 so as to sandwich the back panel 13 as will be described in detail later.

  Each heat sink 37 is used alone or in combination with the heat pipe 36 as a heat radiating member such as a power supply unit in various electronic devices, etc., and is a member that cools the high temperature part by receiving heat conduction from the high temperature part side and radiating heat. It is. Each heat sink 37 has a basic configuration similar to that of a conventional general heat sink, and is formed by extruding or cutting a metal material having high thermal conductivity, such as an aluminum material, and is attached to the back panel 13. And a plurality of fins 47 that stand integrally with the first main surface 46a of the base 46 and radiate heat generated from the LED 18 from the surface.

  Each heat sink 37 has a rectangular shape in which the base 46 has a length substantially equal to the width (height) of the back panel 13. Each heat sink 37 has sufficient mechanical strength because the base 46 has a certain thickness. Each heat sink 37 has a plurality of attachment holes 51 corresponding to attachment holes 50 formed in the back panel 13 and attachment holes 49 formed in the heat dissipation plate 28 as shown in FIGS.

  Each heat sink 37 is formed with a heat dissipating sheet fitting recess 48 for assembling a heat dissipating sheet 44 to be described later on the second main surface 46 b side of the base 46 constituting the mounting surface for the back panel 13. As shown in FIG. 8, the heat radiating sheet fitting recess 48 has an opening size slightly larger than the outer shape of the heat radiating sheet 44 described later, and a depth dimension d slightly smaller than the thickness t of the heat radiating sheet 44. Has been.

  As shown in FIG. 8, each heat sink 37 is integrally formed with a combination portion 54 along one side portion in the width direction. The combination unit 54 configures the heat sink 37 having a predetermined heat dissipation capacity by appropriately combining a plurality of heat sinks 55 and 56 according to the screen size of the liquid crystal panel 8 as will be described later. Each heat sink 37 is formed with a mounting hole 51 penetrating in the thickness direction at an appropriate position of the base 46 and the combination portion 54.

  As shown in FIGS. 6 and 8, each fin 47 is formed of a thin wall-like portion integrally standing on the first main surface 46 a of the base 46 over the entire length direction. The fins 47 are formed on the base 46 so as to face each other in parallel, but it is not particularly necessary to equalize the thickness or the interval. Each fin 47 forms a plurality of cooling space portions 47 a on the first main surface 46 a of the base 46 over the entire length direction.

  Incidentally, since the heat sink 37 is formed by integrally forming a large number of fins 47 with respect to the base 46 as described above, the thickness change increases in the width direction, or changes due to processing accuracy or thermal expansion, or Spring back phenomenon during processing is likely to occur. For this reason, the heat sink 37 is easily warped in the width direction due to the force in the direction shown by the arrow in FIG. In the heat sink 37, the warp of the base 46 occurs in any direction in which each fin 47 is opened or closed depending on processing conditions or the like.

  As will be described later, the heat sink 37 is integrated with the heat radiating plate 23 with the back panel 13 interposed therebetween. However, when the base 46 is warped, the second main surface 46b is made to be opposite to the second main surface 13b of the back panel 13. Therefore, it is difficult to fix in a state of being in close contact over the entire surface. The heat sink 37 reduces the heat conduction efficiency of the heat conduction path formed between the heat sink 37 and the heat radiating plate 23 via the back panel 13 due to a gap generated between the heat sink 37 and the back panel 13. The heat sink 37 deforms the back panel 13 when the mounting screw 52 is strongly tightened to correct the warp of the base 46.

  Therefore, in the liquid crystal display device 1, each heat sink 37 is attached to the back panel 13 via the heat dissipation sheet 44. The heat radiating sheet 44 is formed of, for example, a silicon resin having a certain degree of heat conduction characteristics and elastic deformation characteristics, and has an outer dimension slightly smaller than the opening dimension of the heat radiating sheet fitting recess 48 formed in the heat sink 37 as described above. And has a thickness dimension slightly larger than the depth dimension of the heat radiation sheet fitting recess 48. A plurality of mounting holes 44 a are formed in the heat radiation sheet 44 so as to face the mounting holes 51 on the heat sink 37 side and penetrate in the thickness direction.

  The heat radiating sheet 44 is integrated into the heat radiating sheet fitting recess 48 of the heat sink 37 with an adhesive, for example, so that a part in the thickness direction is exposed from the second main surface 46 b of the base 46. In the heat radiation sheet 44, each mounting hole 44 a communicates with a corresponding mounting hole 51 on the base 46 side.

  In the liquid crystal display device 1, the heat radiating plates 23 constituting the plurality of light emitting arrays 16 are attached to the first main surface 13 a of the back panel 13 at predetermined intervals in the length direction. In the liquid crystal display device 1, the heat sinks 37 are formed on the second main surface 13 b side of the back panel 13, and the heat sinks 37 are bonded to the heat dissipation sheets 44 so as to be orthogonal to the heat dissipation plates 23 on both sides in the length direction. Be placed. Therefore, in the liquid crystal display device 1, as shown in FIG. 3, the overlapping portions where the heat radiating plate 23 and the heat sink 37 overlap with each other are located on both sides in the length direction of the back panel 13 and sandwich the back panel 13. 57 is configured.

  In the liquid crystal display device 1, the mounting holes 49 formed in the heat dissipation plate 23, the mounting holes 50 formed in the back panel 13, and the mounting holes formed in the heat dissipation sheet 44, as shown in FIG. 44a and the attachment hole 51 formed in each heat sink 37 are mutually connected. In the liquid crystal display device 1, the mounting screws 52 are screwed into the mounting holes 49, 50, 44 a and 51, for example, from the heat sink 37 side. In the liquid crystal display device 1, the heat radiating plate 23 and the heat sink 37 are integrated with each mounting screw 52 with the back panel 13 interposed therebetween.

  In the liquid crystal display device 1, as described above, the back panel 13 is slightly thin, and the heat radiating plate 23 and the base 46 of the heat sink 37 are formed with a large thickness. Therefore, in the liquid crystal display device 1, the heat radiating plate 23 and the heat sink 37 are firmly fixed to the back panel 13 without causing partial deformation of the back panel 13 even if each mounting screw 52 is screwed in strongly. It becomes like this. Further, in the liquid crystal display device 1, the back panel 13 is in a state in which the mechanical strength is reinforced throughout by being sandwiched between the heat dissipation plate 23 and the heat sink 37 combined in a lattice shape.

  In the liquid crystal display device 1, as described above, the heat sink 37 is attached to the back panel 13 with the heat radiating sheet 44 joined to the heat radiating sheet fitting recess 48 formed in the base 46. In the liquid crystal display device 1, the heat dissipation sheet 44 is gradually compressed between the back panel 13 and the base 46 in the thickness direction and elastically deformed as the mounting screws 52 are screwed. Therefore, in the liquid crystal display device 1, even when the heat sink 37 is warped in the base 46, the second main surface 46 b of the base 46 is disposed on the back panel 13 via the heat dissipation sheet 44 as shown in FIG. 6. The close contact state with the second main surface 13b is maintained. In the liquid crystal display device 1, with this configuration, a heat conduction path that is in close contact with each other via the back panel 13 and the heat dissipation sheet 44 is formed between the heat dissipation plate 23 and the heatsink 37 so that good heat dissipation is performed. become.

  By the way, in the liquid crystal display device 1, the larger the heat sink 37, the greater the heat dissipation effect. However, the thickness of the backlight unit 3 and the entire device is increased and increased in size. The heat sink 37 is a large and heavy component. For example, when directly attached to a wiring board or the like, a heat conduction member interposed between a mounting bracket member or a high-temperature portion that retains insulation from a circuit component or a wiring pattern or the like. Etc., and the structure is complicated.

  In the liquid crystal display device 1, as described above, each heat sink 37, which is a relatively large component, is skillfully arranged with respect to the back panel 13 using a large number of heat radiation plates 28 and heat pipes 36. In the liquid crystal display device 1, an efficient heat conduction path is configured between the heat radiating plate 28 and the heat pipe 36 via the back panel 13 and the heat radiating sheet 44. Therefore, the liquid crystal display device 1 is configured to efficiently dissipate heat generated from the backlight unit 3 while suppressing an increase in size.

  In the liquid crystal display device 1, as shown in FIGS. 7 and 9, the cooling fan 45 is attached to each heat sink 37, thereby promoting the heat radiation action of the heat sink 37. The cooling fan 45 is also provided in various electronic devices as a device for radiating or cooling from a high temperature part. Although not shown, the cooling fan 45 is attached to a part of the back cover that is combined with the heat sink 37 so as to close the heat radiating space 47 a formed between the fins 47.

  Although details are omitted, the cooling fan 45 includes a housing in which an attachment portion is formed, a motor disposed in the center of the housing via a plurality of arm portions, a fan rotated by the motor, and the like. ing. The main surface of the cooling fan 45 in the thickness direction of the housing is opened, and the cooling fan 45 is attached to the heat sink 37 so that the opening faces the heat radiating space 47a. When the motor is powered on and the fan rotates, the cooling fan 45 promotes heat radiation from the fins 47 by blowing cooling air into the heat radiation space 47a between the fins 47 with respect to the heat sink 37.

  By the way, in the liquid crystal display device 1, since the liquid crystal panel 8 is used in a vertically installed state, the heat generated from each LED 18 rises and gradually becomes trapped in the upper part inside. In the liquid crystal display device 1, the heat generated from each LED 18 is dissipated by the heat dissipating unit 7 including the heat dissipating plate 23, the heat pipe 36, the heat sink 37, and the cooling fan 45 as described above.

  The liquid crystal display device 1 is configured such that the heat dissipation promotion of the heat sink 37 by the cooling fan 45 is performed at an upper portion where the temperature becomes higher. That is, in the liquid crystal display device 1, as shown in FIG. 9, the cooling fan 45 is attached to the heat sink 37 so as to be shifted upward by Δh with respect to the center line OL in the height direction.

  Therefore, in the liquid crystal display device 1, more cooling air is supplied from each cooling fan 45 to the heat sink 37 at the upper portion. In the liquid crystal display device 1, the heat dissipation action in the upper portion of the heat sink 37 is promoted by such a configuration, and the temperature distribution is uniform as a whole. In the liquid crystal display device 1, the liquid crystal panel 8 and each optical plate are at a uniform temperature as a whole, and the occurrence of color unevenness or the like is prevented or a stable operation is performed. Further, in the liquid crystal display device 1, since the high-capacity cooling fan 45 is not required, power consumption is reduced and silence is achieved.

  Note that the cooling fan 45 generally has a substantially square casing, and an attachment portion is formed at each corner portion. When the side surface portion of the housing is attached in parallel to the fins 47 of the heat sink 37, the cooling fan 45 is cooled by the attachment portions blocking a part of the heat radiation space 47 a between the fins 47. The wind blowing efficiency is reduced. Therefore, as shown in FIG. 7, the cooling fan 45 is attached to each fin 47 of the heat sink 37 so as to be inclined at about 90 degrees, so that the cooling air flows from almost the entire opening into the heat radiation space 47a. Blow. Further, the cooling fan 45 may promote heat radiation from the fins 47 by exhausting air from the heat radiation space 47 a between the fins 47.

  In the liquid crystal display device 1, as described above, the heat pipe fitting recess 42 is formed in the heat radiating plate 28, so that a relief recess along the arrangement path is formed in the back panel 13 in order to route the heat pipe 36. Is unnecessary. In the liquid crystal display device 1, the back panel 13 is formed in a flat shape as a whole while being thinned by such a configuration. In the liquid crystal display device 1, heat sinks 37 are mounted on both sides of the back surface of the flat back panel 13 so that a flat portion is formed in the central region of the back panel 13.

  The liquid crystal display device 1 controls the operation of the liquid crystal controller 60 that outputs an operation control signal to the liquid crystal panel 8, the power supply control unit 61 that controls the liquid crystal panel 8 and the power supply unit, or the backlight unit 3. A control circuit package such as an LED control unit 62 is provided. In the liquid crystal display device 1, the back panel 13 also serves as a mounting panel such as a control circuit package, and is appropriately mounted on the second main surface 13b side as shown in FIG. In the liquid crystal display device 1, the above-described control circuit packages and the like are mounted on a control board arranged in a flat region formed in the central portion by arranging heat sinks 37 on both sides.

  In the liquid crystal display device 1, by mounting each control circuit package in a flat region, it is possible to mount the control circuit package without causing a lift or the like by a simple process. In the liquid crystal display device 1, since each control circuit package is generally thin with respect to the heat sink 37, it can be configured to be thin as a whole.

  In the liquid crystal display device 1, for example, when used as a television receiver, screen sizes of, for example, 40 inches, 42 inches, 46 inches, and 55 inches are provided. In the liquid crystal display device 1, as the screen size of the liquid crystal panel 8 increases, more LEDs 18 are provided in the backlight unit 3 to supply a large amount of illumination light in order to maintain display luminance. Composed. In the liquid crystal display device 1, as the number of LEDs 18 increases, the heat generated from each LED 18 also increases, so that efficient heat dissipation must be performed in the heat dissipation unit 7.

  In the liquid crystal display device 1, a heat sink 37 having different heat dissipation capacity characteristics is generally used according to the screen size specification of the liquid crystal panel 8. The heat sink 37 has a heat radiation capacity characteristic defined by the shape of the fin 47, the surface area, and the like, and it is necessary to prepare a plurality of specifications according to the screen size specification. In the liquid crystal display device 1, for example, when a 40-inch liquid crystal panel 8 is used as a reference screen size, a pair of left and right heat sinks 37 and 37 are arranged with respect to the back panel 13 as shown in FIG. 7.

  In the liquid crystal display device 1, when the liquid crystal panel 8 having a screen size larger than the 40-inch liquid crystal panel 8 is provided, a pair of left and right heat sinks 37 are provided with respect to the back panel 13 formed large as shown in FIG. Although the basic configuration is the same, these heat sinks 37 are constituted by a combination of a first heat sink 55 and a second heat sink 56, the details of which will be described later.

  Since the heat sink 37 is formed of an aluminum material or the like as described above, it is considered that a common part is formed by cutting a predetermined size. However, the heat sink 37 has the above-described complicated cross-sectional shape and a length of several tens of centimeters, and it is extremely troublesome to cut and cut the material into a predetermined length and width with high accuracy. In addition, the yield deteriorates and the machining efficiency also deteriorates.

  In the liquid crystal display device 1, a television receiver having a large display screen is generally enlarged on the basis of about 40 inches. In the liquid crystal display device 1, the heat sink 37 uses the shared heat sink material 53 having the width W and the length L shown in FIG. 10, and the shared heat sink material 53 is cut into a predetermined length to form the first heat sink 55. In addition, the second heat sink 56 is configured in combination with a shortage of a desired heat radiation capacity corresponding to the screen size specification. The common heat sink material 53 is manufactured based on, for example, 40 inches, the width W is set to 140 mm sufficient to secure a heat radiation capacity necessary for 40 inches as a reference screen, and the length L is 55 of the maximum screen. It is formed to be long enough to accommodate up to inches.

  The heat sink 37 uses the common heat sink material 53 described above, cuts the common heat sink material 53 into a predetermined length to form the first heat sink 55, and reduces a desired heat radiation capacity deficiency according to the screen size specification. The second heat sink 56 to be complemented is combined. In the common heat sink material 53, a plurality of fins 47 are erected integrally with the base 46, and a combination portion 54 is integrally formed along the one side edge of the base 46 in the entire length direction. Yes. In the common heat sink material 53, a large number of mounting holes 51 are formed in the base 46 at a predetermined interval. The common heat sink material 53 is formed with an attachment portion for attaching the cooling fan 45.

  The shared heat sink material 53 is formed as a first heat sink 55 having a predetermined length by cutting in the width direction at a predetermined position with reference to one end surface in the length direction according to the screen size specification. The first heat sink 55 is efficiently and highly accurately formed by cutting the shared heat sink material 53 in the width direction.

  In the liquid crystal display device 1, when the 40-inch liquid crystal panel 8 is used, the heat sink 37 cuts the common heat sink material 53 into a predetermined length La to form one first heat sink 55 </ b> A (FIG. 12A). Actually, a pair of left and right is provided. Specifically, the first heat sink 55A has a length La of 410 mm and a width Wa of 140 mm.

  In the liquid crystal display device 1, when the 42-inch liquid crystal panel 8 is used, the heat sink 37 cuts the common heat sink material 53 into a predetermined length Lb to form one first heat sink 55 </ b> B (FIG. 12B). Actually, a pair of left and right is provided.) And a second heat sink 56B that complements the shortage of heat radiation capacity. As the heat sink 37, specifically, the first heat sink 55B having a width Wa of 140 mm and a length Lb of 430 mm is used. In addition, the heat sink 37 is formed such that the second heat sink 56B has a common length Lb of 430 mm and a width Xb of 40 mm.

  In the liquid crystal display device 1, when the 46-inch liquid crystal panel 8 is used, the heat sink 37 cuts the common heat sink material 53 into a predetermined length Lc to form a first heat sink 55C ( Actually, a pair of left and right is provided.) And a second heat sink 56C that complements the shortage of heat dissipation capacity. Specifically, the heat sink 37 is used in which the first heat sink 55C has a width Wa of 140 mm and a length Lc of 470 mm. The heat sink 37 is formed so that the second heat sink 56C has a length Lc common to 470 mm and a width Xc of about 53 to 54 mm.

  In the liquid crystal display device 1, when the 55-inch liquid crystal panel 8 is used, one first heat sink 55D (shown in FIG. 12D) in which the heat sink 37 cuts the common heat sink material 53 into a predetermined length Ld. Actually, a pair of left and right is provided.) And a second heat sink 56D that complements the shortage of heat dissipation capacity. Specifically, the heat sink 37 is used in which the first heat sink 55D has a width Wa of 140 mm and a length Ld of 560 mm. Further, the heat sink 37 is formed such that the second heat sink 56D has a common length Ld of 560 mm and a width Xd of about 140 mm. Therefore, the heat sink 37 is configured by combining the first heat sink 55D and the second heat sink 56D having the same shape.

  In the liquid crystal display device 1, as described above, the 40-inch liquid crystal panel 8 is used as a reference display panel, and a long shared heat sink material 53 having a width W suitable for the reference display panel is prepared in advance. In the liquid crystal display device 1, when the liquid crystal panel 8 having a screen size larger than that of the reference display panel is used, the common heat sink material 53 is processed to be cut into a predetermined length suitable for the applicable display panel. The first heat sink 55 is used, and the first heat sink 55 is combined with a second heat sink 56 that complements the shortage of heat dissipation capacity. In the liquid crystal display device 1, parts can be shared for various types of specifications and a quick response can be achieved, and an optimum specification heat sink 37 is configured to perform heat radiation with high accuracy.

  Note that the liquid crystal display device 1 is not limited to the configuration in which the heat sink 37 is configured by combining the first heat sink 55 and the second heat sink 56 having the above-described dimension values selected corresponding to each screen specification. Of course. In the liquid crystal display device 1, the heat sink characteristic of the shared heat sink material 53 forming the first heat sink 55 is determined by the size and quantity of the fins 47, and the length L and width W thereof are changed. In the liquid crystal display device 1, the second heat sink 56 has the same length as the first heat sink 55 and is combined so that the mounting structure for the back panel 23 and the like is made common and the uniform heat radiation function is achieved. It is preferable to be integrated through the portion 54. In the liquid crystal display device 1, the mounting portion of the cooling fan 45 is formed only on the first heat sink 55 side, so that the structure of the second heat sink 56 can be simplified by simplifying the structure.

  In the liquid crystal display device 1, a heat radiation sheet is sandwiched between the back panel 13 and the heat sink 37 to configure an efficient heat conduction path. However, such a configuration is provided between the wiring board 17 and the heat radiation plate 23. You may make it provide. In the liquid crystal display device 1, a heat radiating sheet having an outer dimension slightly smaller than the opening dimension of the substrate fitting recess 38 formed in the heat radiating plate 23 and having a thickness slightly larger than the depth of the substrate fitting recess 38 is used. . In the liquid crystal display device 1, the heat dissipation sheet is crushed in the thickness direction by fixing the wiring substrate 17 to the heat dissipation plate 23, and an efficient heat conduction path is configured between the heat dissipation plate 23 and the wiring substrate 17. Become so.

  Although the above-described embodiment has shown the transmissive liquid crystal display device 1 for a display panel of a television receiver having a large display screen of 40 inches or more, the present invention is applied to various liquid crystal display devices having a large screen. Of course. In addition, the present invention is extremely effective when applied to a large display device, but can also be applied to a medium-sized display device.

It is a principal part disassembled perspective view of the transmissive liquid crystal display device shown as embodiment. It is a principal part longitudinal cross-sectional view of a transmissive liquid crystal display device. It is a partially notched top view which shows the structure of a light guide part, a backlight unit, and a reflection part. It is a principal part disassembled perspective view which shows the light emission unit body, the reflection plate of a reflection part, and a reflection sheet piece. It is a principal part longitudinal cross-sectional view which shows the light emission unit body attached to a back panel. It is a principal part longitudinal cross-sectional view which shows the light emission unit body and heat sink which are attached to a back panel. It is a principal part rear view. It is a decomposition | disassembly longitudinal cross-sectional view which shows a heat sink and a thermal radiation sheet. It is a principal part perspective view of the back side. It is a principal part top view of a common heat sink material. It is a principal part perspective view of the back side of the transmissive liquid crystal display device shown as another form. It is explanatory drawing of the combination aspect of a heat sink.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Liquid crystal display device, 2 Liquid crystal panel unit, 3 Backlight unit, 4 Optical conversion part, 5 Light guide part, 6 Reflection part, 7 Heat radiation part, 8 Liquid crystal panel, 13 Back panel, 14 Light guide space part, 15 Light emitting unit Body, 16 light emitting array, 17 wiring board, 18 LED, 21 diffused light guide plate, 23 diffused plate, 24 dimming pattern, 25 optical stud member, 26 reflective plate, 27 reflective sheet piece, 28 heat radiating plate, 36 heat pipe, 37 Heat sink, 38 Substrate fitting recess, 39 Mounting screw, 44 Heat radiation sheet, 45 Cooling fan, 46 Base, 47 Fin, 48 Heat sink sheet fitting recess, 49 Mounting hole, 50 Mounting hole, 51 Mounting hole, 52 Mounting screw, 53 Common heat sink material, 54 Combined part, 55 1st heat sink, 56 1st 2 heat sink, 60 LCD controller, 61 power supply control unit, 62 LED control unit

Claims (2)

A plurality of light-emitting unit bodies each having a plurality of light-emitting diodes mounted on a wiring board are arranged to form a plurality of light-emitting arrays, and these light-emitting arrays are arranged on the rear surface of the transmissive display panel so as to Provided in a transmissive display device for supplying emitted illumination light to the display panel,
A heat radiating plate that is formed of a metal material having high thermal conductivity characteristics and constitutes the light emitting unit body by supporting each wiring board on the first main surface;
A back panel formed of a metal material having high thermal conductivity characteristics, and mounted on the first main surface by fixing the second main surface to the heat dissipation plate so as to face the display panel;
The base is formed of a metal material having a high thermal conductivity characteristic, and includes a base and a plurality of fins standing integrally with each other at a predetermined interval on the first main surface of the base. A heat sink that is attached to the second main surface of the back panel with the main surface as an attachment surface, and that dissipates heat from the fins by the heat generated by the lighting operation of the light emitting diodes being conducted by heat conduction means,
A heat-dissipating sheet interposed between the second main surface of the back panel and the second main surface of the heat sink, and formed of an elastic material that is in close contact with the back panel and the heat sink to form a heat conduction path; With
On the second main surface of the heat sink, a heat dissipating sheet fitting recess having an opening dimension larger than the outer dimension of the heat dissipating sheet and a depth dimension smaller than the thickness dimension is formed,
The heat radiating sheet fitted in the heat radiating sheet fitting recess is crushed in the thickness direction by attaching the heat sink to the back panel, and is closely attached to the back panel and the heat sink. apparatus. A transmissive display panel that performs optical display with illumination light supplied from the back side;
A plurality of light-emitting blocks having a plurality of light-emitting diodes, a wiring board on which these light-emitting diodes are mounted, and a heat radiating plate that is formed of a metal material having high thermal conductivity and supports the wiring boards on the first main surface A backlight unit that arranges the body on the back side of the display panel to form a plurality of light emitting arrays, and supplies the illumination light emitted from the light emitting diodes to the display panel;
A light conversion light guide that is disposed between the display panel and the backlight unit and performs a predetermined light conversion process and a uniform process on the illumination light to be supplied to the display panel;
A back panel that is formed of a metal material having a high thermal conductivity, and is attached to the first main surface by fixing the second main surface to the display panel so as to face the display panel;
The base is formed of a metal material having a high thermal conductivity characteristic, and includes a base and a plurality of fins standing upright integrally with each other at a predetermined interval on the first main surface of the base. A heat sink that is attached to the second main surface of the back panel as a mounting surface, and that dissipates heat from the fins by conducting heat generated by the lighting operation of the light-emitting diodes by heat conduction means,
A heat-dissipating sheet interposed between the second main surface of the back panel and the second main surface of the heat sink, and formed of an elastic material that is in close contact with the back panel and the heat sink to form a heat conduction path; With
On the second main surface of the heat sink, a heat dissipating sheet fitting recess having an opening dimension larger than the outer dimension of the heat dissipating sheet and a depth dimension smaller than the thickness dimension is formed,
The display, wherein the heat dissipation sheet fitted in the heat dissipation sheet fitting recess is crushed in the thickness direction by attaching the heat sink to the back panel and is in close contact with the back panel and the heat sink apparatus.

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