JP2010008715A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device of which operation can be guaranteed even under high temperature. <P>SOLUTION: This display device comprises a liquid crystal display panel 1 (display panel) in which the end of a flexible printed wiring board 13 and a drive circuit 14 are fixed to one end 12, a case 2 accommodating the liquid crystal display panel 1, a light emitting diode 4 arranged along the inner side of the side wall 3 of the case 2, a light guide plate 6 having a light receiving part 5 opposing to the light emitting diode 4, and a panel presser 7 which presses the periphery of the liquid crystal display panel 1. The light emitting diode 4 is provided to the side wall 3 of the case 2 not correspond to the one end part 12. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device provided in, for example, a vehicle instrument, and more particularly to a display device using a liquid crystal display panel.

As this type of display device, for example, there is one disclosed in Patent Document 1. In the light guide unit (display device) described in Patent Document 1, a light guide plate 15, a light source circuit board 17 on which a light source 13 is mounted, a liquid crystal panel 10, and the like are housed in a housing 102. The liquid crystal panel 10 is illuminated with the light guided into the light guide plate 15.
JP 2008-52074 A

  Such a display device may be provided in a vehicle and required to guarantee operation at high temperatures. In the light guide unit of Patent Document 1, since the light source 13 is arranged behind the semiconductor element 91 (driving circuit) and the FPC 93 mounted on the element substrate 60, the light source 13 is turned on in a high temperature atmosphere. The semiconductor element 91 may exceed the guaranteed operating temperature (about 85 degrees) of the semiconductor element 91 under the influence of heat generated from the light source 13. As a result, the liquid crystal panel 10 may not display. Similarly, the heat-resistant temperature (85 ° to 90 °) of the FPC 93 may be exceeded, and the liquid crystal panel 10 may not display.

  The present invention has been made in view of these points, and an object of the present invention is to provide a display device that can guarantee operation even at high temperatures.

  In order to achieve the above object, the present invention has an end of a flexible printed wiring board and a drive circuit fixed to one end, or an end of a flexible printed wiring board having a drive circuit mounted to one end. A display panel, a case disposed behind the display panel and housing the display panel, a light source disposed along an inner side wall of the case, and the display panel and the case. In a display device comprising: a light guide plate having a light receiving portion disposed opposite to the light source; and a panel holding member that suppresses a peripheral portion of the display panel, the light source is provided on a side wall of the case that does not correspond to the one end portion. It is provided.

  Further, the case is made of a metal material, and a heat radiating member is placed in contact with the back surface of the case.

  A display device that can guarantee operation even at high temperatures can be obtained.

  A display device provided in a vehicle will be described as an embodiment. FIG. 1 is a front view of a display device showing a first embodiment of the present invention. FIG. 2 is a front view showing a state in which a flexible printed wiring board and a drive circuit are fixed to a liquid crystal display panel (display panel) used in the display device. 3 is a cross-sectional view of the display device (cross-section AA in FIG. 1), and FIG. 4 is a cross-sectional view of the display device (cross-section BB in FIG. 1).

  The display device includes a rectangular transmissive liquid crystal display panel 1 (display panel), a case 2 disposed behind the liquid crystal display panel 1 and housing the liquid crystal display panel 1, and an inner side of the side wall 3 of the case 2. A light emitting diode 4 (light source) disposed along the light guide plate 6, a light guide plate 6 having a light receiving portion 5 disposed between the liquid crystal display panel 1 and the case 2 and facing the light emitting diode 4, and the liquid crystal display panel 1. A panel holder 7 for holding the peripheral edge portion is provided. In this embodiment, an optical film 8 such as a diffusion sheet or a prism sheet is provided on the front side of the light guide plate 6, and a frame body 9 that suppresses the peripheral portion of the optical film 8. 1 is disposed on the frame 9.

  The liquid crystal display panel 1 is a dot matrix type having pixels (dots) arranged in a matrix. Although details are omitted (not shown), the first glass substrate 10 and the second glass substrate 11 each formed with a transparent electrode made of ITO and a routing electrode connected to the transparent electrode are overlapped to seal the periphery. After fixing with the agent, liquid crystal molecules are sealed between the glass substrates 10 and 11, and a smoke-like polarizing film is pasted on the glass substrates 10 and 11, for example.

  The end portion of the flexible printed wiring board 13 is fixed to one end portion 12 (one end of the quadrangle) on the surface side of the second glass substrate 11 and is connected to a lead electrode to drive the liquid crystal display panel 1. (IC) is mounted. In addition, an electrode part (not shown) for connecting the flexible printed wiring board 13 and the drive circuit 14 is provided. When a signal (voltage) corresponding to the external measurement amount is applied to the transparent electrode through the flexible printed wiring board 13, various information such as the operating state of the vehicle and various warning messages is displayed on the liquid crystal display panel 1. It is like that.

  The flexible printed wiring board 13 is not shown in detail, but a conductive part (conductive circuit) made of a copper foil connected to the electrode part is formed, for example, by etching on a synthetic resin base film made of polyimide resin, for example. After that, a protective film for insulation protection is bonded.

  The case 2 is substantially the same shape as the liquid crystal display panel 1 and is made of, for example, aluminum, which is a metal material. The formed locking portion 16 is provided. The locking portion 16 is to which the frame body 9 is attached, and protrudes outward from the bottom wall 15 side of the side wall 3.

  A plurality of light emitting diodes 4 are arranged on the inner side of the side wall 3 toward the light guide plate 6 via FPCs 17 in which conductive circuits for lighting the light emitting diodes 4 are formed. The side wall 3 on which the light emitting diode 4 is disposed is the side wall 3 of the case 2 that does not correspond to the one end 12 of the liquid crystal display panel 1 to which the end of the flexible printed wiring board 13 and the drive circuit 14 are fixed. . That is, other than the one end 12 of the liquid crystal display panel 1 to which the end of the flexible printed wiring board 13 and the drive circuit 14 are fixed, the other end 18 facing the one end 12 of the liquid crystal display panel 1 is supported. This is the side wall 3 of the case 2.

  The light guide plate 6 is made of a synthetic resin such as colorless and transparent acrylic or polycarbonate, and a light receiving portion 5 is provided on a side surface facing the light emitting diode 4. In addition, fine irregularities (textures) are formed on the back surface so that light from the light emitting diode 4 incident on the light guide plate 6 from the light receiving portion 5 is reflected by the irregularities and travels toward the front surface side of the light guide plate 6. It has become. The light guide plate 6 is accommodated in the case 2.

  The frame body 9 is made of, for example, a stainless steel plate that is a metal material, and has an edge portion 19 and a peripheral wall portion 20. The edge 19 holds the optical film 8 and the peripheral portion of the liquid crystal display panel 1 so that the liquid crystal display panel 1 and the optical film 8 do not move in the case 2. After being stored in the case 2, the frame body 9 is engaged with the case 2.

  Hole portions 21 are provided at 20 locations on the peripheral wall portion 20 of the frame body 9 (locations corresponding to the locking portions 16 formed on the case 2). Although details are omitted, the locking portion 16 is locked to the cut surface of the hole portion 21 so that the frame body 9 is engaged with the case 2. In the present embodiment, the liquid crystal display panel 1 is disposed on the edge portion 19 of the frame body 9. Further, a plurality of frame locking portions 22 are provided at appropriate locations around the peripheral wall portion 20. The frame body locking portion 22 is to which the panel retainer 7 is attached, and, like the locking portion 16 formed in the case 2, projects the bottom wall 15 side of the peripheral wall portion 20 outward. .

  The panel retainer 7 is made of, for example, a stainless steel plate, which is a metal material, and includes a panel edge 23 that restrains the peripheral portion of the liquid crystal display panel 1, an enclosure 24 that surrounds the periphery of the frame 9, and a display area of the liquid crystal display panel 1. An opening hole 25 is defined. Moreover, the panel hole part 26 is provided in 24 enclosure parts (location corresponding to the frame latching | locking part 22 formed in the frame 9). Although details are omitted, the frame body locking portion 22 is locked to the cut surface of the panel hole 26 so that the panel retainer 7 is engaged with the frame body 9.

  Thus, the liquid crystal display panel 1 in which the end of the flexible printed wiring board 13 and the drive circuit 14 are fixed to the one end 12, the case 2 in which the liquid crystal display panel 1 is stored, and the side wall 3 of the case 2. A display device including a light emitting diode 4 disposed along the inner side of the liquid crystal display panel, a light guide plate 6 having a light receiving portion 5 opposed to the light emitting diode 4, and a panel holding member 7 for suppressing a peripheral portion of the liquid crystal display panel 1. In this case, since the light emitting diode 4 is separated from the flexible printed wiring board 13 and the driving circuit 14 by providing the light emitting diode 4 on the side wall 3 of the case 2 that does not correspond to the one end portion 12, the flexible printed wiring board 13 and the driving circuit. 14 is hardly affected by the heat from the light emitting diode 4, the guaranteed operating temperature of the drive circuit 14, and the heat resistance of the flexible printed wiring board 13. Without exceeding the degree, there is no possibility that the liquid crystal display panel 1 is no longer displayed.

  In the above embodiment, the liquid crystal display panel 1 is disposed on the side wall 3 of the case 2 corresponding to the other end 18 facing the one end 12. You may make it arrange | position on the side wall 3 of the case 2 corresponding to the other end part 18A (refer FIG. 2) of the both sides to which the circuit 14 was fixed. Even in this case, the same effect can be obtained.

  Moreover, although the case 2, the panel holding member 7, and the frame 9 are made of metal, they may be made of resin. However, metal is more effective for heat dissipation. In particular, since the case 2 is made of metal, heat from the light emitting diode 4 is transmitted to the case 2 and easily radiated, so the case 2 is preferably made of metal.

  Further, in this embodiment, the optical film 8 and the frame body 9 are provided, but the optical film 8 and the frame body 9 are abolished even if the satisfactory illumination and holding structure of the liquid crystal display panel 1 can be obtained. For example, the light guide plate 6 and the liquid crystal display panel 1 may be held by the case 2 and the panel holder 7.

  In addition, the end portion of the flexible printed wiring board 13 and the drive circuit 14 are fixed to the one end portion 12 on the surface side of the second glass substrate 11, but the driving is performed on the end portion side of the flexible printed wiring board 13. The end portion of the flexible printed wiring board 13 on which the circuit 14 is mounted may be fixed to the one end portion 12 on the surface side of the second glass substrate 11. Even in this case, the same effect can be obtained.

  FIG. 5 is a cross-sectional view of a display device showing a second embodiment of the present invention, and corresponds to the AA cross section of FIG. The display device according to the present embodiment has a heat radiating member 27 disposed on the back surface of the case 2, and the other parts are the same as those of the first embodiment. The detailed description is omitted.

  The heat radiating member 27 is brought into contact with the back surface of the bottom wall 15 of the case 2, and an attachment fixing portion 28 attached to the bottom wall 15 and plate-like heat radiation fins 29 erected on the attachment fixing portion 28 at a predetermined interval. Have more than one.

  The case 2 is made of, for example, aluminum, which is a metal material and has a high thermal conductivity. The case 2 has substantially the same shape as the case 2 in the first embodiment, but a mounting portion (not shown) to which the heat dissipation member 27 is attached (for example, a screw). When the heat radiating member 27 is attached using a screw hole) is provided in the bottom wall 15.

  As described above, the case 2 is made of aluminum, which is a metal material, and the heat radiating member 27 made of aluminum having high thermal conductivity is placed in contact with the back surface of the case 2 so that the heat of the light-emitting diode 4 transmitted to the case 2 can be obtained. Can be radiated by the heat radiating member 27. Further, by providing the heat dissipation fins 29 on the heat dissipation member 27, the heat dissipation area is widened and the heat dissipation is improved. Therefore, it is possible to further reduce the temperature in the display device, and it is possible to provide a display device that can guarantee operation even in a high-temperature atmosphere. The heat radiating member may be a member that efficiently radiates heat transferred to the case 2 to the outside, and may be a heat pipe, for example.

The front view of the display apparatus which shows 1st Embodiment of this invention. The front view which shows the state by which the flexible printed wiring board and the drive circuit were fixed to the display panel used for the display apparatus. Sectional drawing (AA cross section in FIG. 1) of the display apparatus. Sectional drawing of the display apparatus (BB cross section in FIG. 1). Sectional drawing (equivalent to the AA cross section of FIG. 1) of the display apparatus which shows 2nd Embodiment of this invention.

Explanation of symbols

1 Liquid crystal display panel (display panel)
2 Case 3 Side wall 4 Light-emitting diode (light source)
DESCRIPTION OF SYMBOLS 5 Light-receiving part 6 Light-guide plate 7 Panel holding | suppressing 12 One end part 13 Flexible printed wiring board 14 Drive circuit 27 Heat dissipation member

Claims (2)

  A display panel in which the end of the flexible printed wiring board and the drive circuit are fixed to one end, or the end of the flexible printed wiring board in which the drive circuit is mounted is fixed to one end, and behind the display panel A case in which the display panel is housed, a light source disposed along an inner side wall of the case, and a light receiving portion disposed between the display panel and the case and facing the light source. A display device comprising: a light guide plate having a panel; and a panel holding member that suppresses a peripheral portion of the display panel, wherein the light source is provided on a side wall of the case that does not correspond to the one end. apparatus.   The display device according to claim 1, wherein the case is made of a metal material, and a heat radiating member is disposed in contact with a back surface of the case.

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