JP2009086069A - Display module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display module superior in reliability wherein a display panel is surely held in a prescribed position over a long period of time. <P>SOLUTION: A liquid crystal display panel 2, a surface emission backlight unit 6, and a drive control circuit board 7 are stored in a resin frame case 1 so as be held in prescribed positions respectively, and a shield case 9 formed by forming a stainless plate is provided so as to cover a case bottom wherein the drive control circuit board 7 is installed. An end part of the liquid crystal display panel 2, to which a main FPC 4 is made conductive and joined, and a corresponding end part of the frame case 1 are elastically held by a channel-shaped cross-section part formed by bending a front end part 921 of a shorter-side plate 92 of the shield case 9 inward at right angles. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a flat panel display module.

  In recent years, an image display module using a flat panel display (hereinafter referred to as FPD: Flat Panel Display) such as a liquid crystal display panel or an organic electroluminescence display panel is advantageous in reducing the thickness of an applied device. (Personal Digital Assistance) is widely used as a display for mobile devices.

In an FPD used as a display for such a mobile device, a double-sided pressure-sensitive adhesive tape that is excellent in terms of workability, dustproof sealability, and the like is used as a fixing member for fixing a display panel (see Patent Document 1). ).
Japanese Patent Laid-Open No. 2004-361654

  However, the adhesive strength of the double-sided pressure-sensitive adhesive tape deteriorates with the passage of time and changes in environmental conditions such as temperature and humidity, so that the display panel is easily peeled off from the frame during long-term use. That is, it becomes a problem in terms of durability as a display module.

  An object of the present invention is to provide a display module with excellent reliability in which a display panel is securely held at a predetermined position over a long period of time.

  The display module according to claim 1 of the present invention is formed of a display panel, a resin material, a frame that supports the display panel, and an elastic material having a smaller coefficient of thermal expansion than the frame. And a shield case having a U-shaped cross-sectional portion that collectively clamps one end portion of the display panel and the corresponding one end portion of the frame by elastic force.

  A display module according to a second aspect is the display module according to the first aspect, wherein the shield case is formed by processing a thin stainless plate.

  According to a third aspect of the present invention, in the display module according to the first aspect, a liquid crystal display panel, a surface emitting irradiation panel, and a drive control circuit board that controls driving of the entire module are arranged at predetermined positions via a frame. The liquid crystal display module is a liquid crystal display module in which the liquid crystal display panel, the surface emitting irradiation panel, and the drive control circuit board are connected to each other by a flexible wiring board and are housed and held in the shield case together with the frame. Is.

  In the display module to which the present invention is applied, the display panel is reliably held at a predetermined position for a long time, and the reliability as the display module is improved.

  1 is a schematic cross-sectional view showing a liquid crystal display module as one embodiment of the present invention, FIG. 2 is an exploded perspective view showing a part of the liquid crystal display module, and FIG. (B) is a plan view and a side view of the liquid crystal display module.

  As shown in FIG. 1, the liquid crystal display module of this embodiment includes an open top frame case 1 in which two rectangular parallelepiped storage spaces having different sizes are formed in two layers. The two storage spaces have a flat rectangular parallelepiped having a flat area smaller than the front chamber 1a of the flat rectangular parallelepiped with the viewing side of the opened display as the front side and the area of the shelf 11 than this. It consists of a rear chamber 1b of the space.

  As shown in FIG. 2, a notch 121 is formed in one short side plate 12 of the four side plates 12 to 15 of the frame case 1. On the outer surfaces of the pair of side plates 13, 15 in the longitudinal direction, a pair of locking projections 16, 16 are projected at predetermined positions, respectively. Each locking projection 16 forms a quadrangular prism having one side surface 161 formed on an inclined surface. Then, stepped surfaces 17 and 17 are respectively provided on the end portions of the long side plates 13 and 15 opposite to the short side plate 12 side where the notches 121 are formed. The frame case 1 having such a shape is formed by, for example, an injection method using a resin material.

  Returning to FIG. 1, the liquid crystal display panel 2 is accommodated in the front chamber 1 a of the frame case 1. The liquid crystal display panel 2 includes a pair of rectangular glass substrates 21 and 22 each having an electrode (not shown) formed on one main surface thereof, and a frame-shaped sealing material (not shown) with the electrode forming surfaces facing each other. The liquid crystal (not shown) is sealed between the glass substrates 21 and 22 surrounded by a frame-shaped sealing material. Front and rear polarizing plates 23 and 24 are attached to the outer surfaces of the glass substrates 21 and 22, respectively.

  Of the glass substrates 21 and 22, the rear glass substrate 22 is formed with a projecting portion 221 by projecting one short side edge outward from the corresponding end surface of the front glass substrate 21. A driver chip 3 as a liquid crystal driving circuit element is mounted on the surface of the protruding portion 221 (extension surface of the electrode forming surface) by a COG (Chip On Glass) method. Further, connection terminals (not shown) of the lead wirings connected to the electrodes of the two substrates 21 and 22 are arranged in parallel at the end of the protruding portion 221. A main flexible wiring board (hereinafter referred to as FPC (Flexible Printed Circuit Board)) 4 for supplying drive control signals is conductively joined to the connection terminal row. The main FPC 4 is drawn out of the frame case 1 from a notch 121 (see FIG. 2) formed in the frame case side plate 12.

  The liquid crystal display panel 2 described above is installed in a state where the peripheral edge of the glass substrate 22 is supported by the shelf 11 of the frame case 1 thereafter. A double-sided pressure-sensitive adhesive sheet 5 is disposed on the shelf 11, and the liquid crystal display panel 2 is fixed to the frame case 1 via the double-sided pressure-sensitive adhesive sheet 5.

  A surface emitting backlight unit 6 is housed and installed in the back side opposite to the viewing side of the display of the liquid crystal display panel 2, that is, in the rear chamber 1b. In the backlight unit 6 of the present embodiment, a plurality of LEDs (Light-Emitting Diodes) 62 as light source elements are provided at one end of a transparent light guide plate 61 having a rectangular shape that roughly corresponds to the liquid crystal display panel 2 to be irradiated. The optical sheet laminate 63 is installed on the front surface 611 of the light guide plate 61 facing the liquid crystal display panel 2 and the light reflection sheet 64 is installed on the rear surface 612 on the opposite side.

  The LED 62 is directly mounted on the FPC 65 by a COF (Chip On Film) method, and the light source FPC 65 is disposed adjacent to the light reflecting sheet 64. The light source FPC 65 is pulled out of the frame case 1 from a notch (not shown) provided in the frame case 1 and is conductively connected to a predetermined portion of the main FPC 4 joined to the liquid crystal display panel 2 described above.

  On the light emitting surface (front surface) 611 of the light guide plate 61, an optical sheet laminate 63 as a light control member is installed. The optical sheet laminate 63 is formed by sequentially laminating a lower diffusion sheet 631, a prism sheet 632, and an upper diffusion sheet 633 on the light emitting surface 611.

  On the rear surface 612 of the light guide plate 61, a concavo-convex pattern (not shown) is formed for uniformly reflecting the light emitted from the LEDs 62 and entering the light guide plate 61 toward the front surface 611. A light reflecting sheet 64 made of a white PET (polyethylene terephthalate) sheet is installed on the rear surface 612.

  In the backlight unit 6 configured as described above, the light emitted from the LED 62 enters the light guide plate 61 from its opposite end surface, and when this incident light enters the concave-convex pattern on the rear surface 612, Internally reflected toward the front surface 611 and emitted from the front surface 611 in a planar shape. The emitted light passes through the optical sheet laminate 63 and is irradiated onto the liquid crystal display panel 2 as planar irradiation light having a uniform luminance distribution and high front luminance. There is also light that exits from the light guide plate 61 after entering the concavo-convex pattern. However, the emitted light is reflected by the light reflecting sheet 64 and re-entered into the light guide plate 61, thereby causing the light from the LED 62 to be incident. The utilization efficiency of the emitted light is increased.

  The drive control circuit board 7 is mounted on the rear surface (outer surface) of the bottom plate 18 of the frame case 1. In the present embodiment, the corresponding end portions of the drive control circuit board 7 are engaged by a plurality of engagement hooks 19 erected on the outer surface of the case bottom plate 18, and the drive control circuit board 7 is held at a predetermined position. . This drive control circuit board 7 controls the drive of the entire liquid crystal display module, and is electrically connected to the liquid crystal display panel 2 and the surface light emitting backlight unit 6 by the main FPC 4 to which the light source FPC 65 is electrically connected. Yes.

  That is, one end of the main FPC 4 is conductively joined to the connection terminal row at the end of the protruding portion 221 in the liquid crystal display panel 2 housed in the front chamber 1a of the frame case 1, and the frame case 1 1 is pulled out and extended downward (on the opposite side) along the outer surface of the case side plate 12, and then bent to the rear of the bottom plate 18, and the bent end portion is inserted into the connector 8 and driven. The control circuit board 7 is conductively connected.

  As described above, the frame case 1 in which the liquid crystal display panel 2, the surface light emitting backlight unit 6, and the drive control circuit board 7 are attached to predetermined portions is covered with the shield case 9 so as to cover the bottom side. Yes.

  As shown in FIG. 2, the shield case 9 has a box shape in which a part of the upper surface and side surfaces of the rectangular parallelepiped are opened, and is formed of an elastic material having a smaller coefficient of thermal expansion than the resin material forming the frame case 1. Yes. The shield case 9 of this embodiment is manufactured by sheet metal processing of a stainless steel thin plate.

  Of the side plates 92 to 94 erected on the three sides of the bottom plate 91 having a rectangular shape of the shield case 9, a short side plate (hereinafter referred to as a frame short side plate) in which the cutout portion 121 of the frame case 1 is formed. 12, a short side plate (hereinafter referred to as a case short side plate) 92 corresponding to 12 has a distal end portion 921 bent inward at a right angle.

  A pair of rectangular holes 95 are formed in the pair of case long side plates 93 and 94 so as to correspond to the locking projections 16 of the frame case 1, respectively. Each rectangular hole 95 is formed in such a size that an appropriate surplus space is secured when it is extrapolated to the locking projection 16, but the drilling position is set accurately as follows.

  That is, the distances L1 and L2 from the open side end surfaces 931 and 941 of the case long side plates 93 and 94 to the respective rectangular holes 95, and the distances D1 from the step surfaces 17 of the frame long side plates 13 and 15 to the respective locking projections 16; D2 is set to a substantially equal dimension. Thereby, the shield case 9 can be attached to the frame case 1 without rattling.

  Here, the respective central portions of the case longitudinal side plates 93 and 94 are cut out to an appropriate length to form cutout portions 932 and 942. These central cutout portions 932 and 942 indicate the shield case 9 with an arrow. It becomes an escape portion for minimizing the bending of the case side plates 93 and 94 due to the sliding contact with the locking projection 16 when the frame case 1 is slid in the A direction.

  When the shield case 9 is slidably mounted on the frame case 1, the open side surface of the shield case 9 is extrapolated to the short side plate 12 provided with the notch 121 of the frame case 1, and then the shield case 9 is attached to the frame case. 1 is pushed in the direction of arrow A along the longitudinal direction. Thereby, first, the open side end surfaces 931 and 941 of the long side plates 93 and 94 are brought into sliding contact with the inclined surfaces 161 of the locking projections 16 and 16 on the front side (relative to the pushing direction), and the longitudinal effect is gradually increased. When the side plates 93 and 94 are respectively pushed down to the outside and further pushed in, the corresponding front side locking projections 16 are fitted into the rectangular holes 95 and 95 on the open side (tip side in the pushing direction).

  Thereafter, when the shield case 9 is further pushed in, the sliding engagement between the front side locking projections 16 and the long side plates 92 and 93 starts again, and both the long side plates 92 and 93 are gradually pushed down to the outside. The locking protrusion 16 enters the corresponding central notch 932, 942. Thereby, the longitudinal side plates 93 and 94 of the shield case 9 return to the original upright state by their own elasticity.

  When the shield case 9 is further pushed in from this state, the locking projections 16 on both the front side and the back side of the frame longitudinal side plates 13 and 15 are in sliding contact with the case longitudinal side plates 93 and 94, respectively, When the end surfaces 931 and 941 abut against the corresponding stepped surface 17 and the pushing operation is prevented, all four locking projections 16 are fitted into the corresponding rectangular holes 95, and the slide mounting of the shield case 9 is completed. To do.

  In this slide mounting operation, the opposing case longitudinal side plates 93 and 94 are forced to be opened. However, since the notch portions 932 and 942 having a considerable length are provided in the central portion, each case longitudinal side plate 93 is provided. , 94 can be suppressed as much as possible. As a result, the push-in operation of the shield case 9 is facilitated, and deformation exceeding the elastic limit of the case longitudinal side plates 93, 94 is prevented. The

  When the shield case 9 is completely attached, as shown in FIG. 3, the open side end surfaces 931 and 941 are in contact with the corresponding stepped surfaces 17 in the pushing direction A of the shield case 9 as described above. The movement is prevented, and with respect to the detachment directions B and C, the end surfaces of four (two are not shown) rectangular holes 95 are engaged with the side surfaces of the corresponding locking projections 16 to Movement along each direction B, C is prevented. In this way, the shield case 9 is mounted on the frame case 1 without rattling.

  As shown in FIG. 1, the end portion 921 bent at a right angle to the inside of the case short side plate 92 has an end portion of the liquid crystal display panel 2 supported by the shelf portion 11 of the frame case 1 from above the main FPC 4. Elastically abuts. That is, the end of the liquid crystal display panel 2 where the main FPC 4 of the glass substrate 22 is conductively bonded is fixed to the shelf 11 by the double-sided adhesive sheet 5 together with the corresponding end of the frame case 1 and the main FPC 4. The short side plate 92 of the shield case 9 is elastically clamped by the U-shaped cross-section portion provided upright.

  Even if the adhesive force of the double-sided pressure-sensitive adhesive sheet 5 deteriorates due to the passage of time over time or changes in environmental conditions such as temperature and humidity, the elastic clamping structure can stably stabilize the liquid crystal display panel 2 at a predetermined position without peeling off. Can be held. Even if the resin frame case 1 is warped by heat or the like, the shield case 9 is formed of a stainless steel plate having a smaller coefficient of thermal expansion than that, so that the warp can be effectively corrected. Peeling from the end of the glass substrate 22 can also be prevented.

  As described above, the liquid crystal display module of the present embodiment is a shield made of a stainless steel plate that covers the frame case 1 with the liquid crystal display panel 2 mounted using the double-sided adhesive sheet 5 at a predetermined position of the resin frame case 1. Since it is configured to be elastically clamped together with the frame case 1 by the U-shaped cross section of the case 9, even if the adhesive force of the double-sided pressure-sensitive adhesive sheet 5 deteriorates due to the passage of time over time, changes in environmental conditions such as temperature, humidity, The liquid crystal display panel 2 can be stably held at a predetermined position.

In addition, this invention is not limited to said embodiment.
For example, in the above embodiment, the liquid crystal display panel 2 is fixed to the frame case 1 using the double-sided pressure-sensitive adhesive sheet 5, but the display panel is supported by the frame without causing a gap to move in the plane direction, The adhesive member such as the double-sided pressure-sensitive adhesive sheet 5 can be omitted by adopting a structure in which the frame is sandwiched evenly by the shield case.

  The material of the shield case is not limited to a metal such as stainless steel, and a natural material having elasticity such as wood or bamboo having a smaller coefficient of thermal expansion than the resin material can also be used.

  In addition, the present invention is not limited to a transmissive liquid crystal display module having a backlight as in the above embodiment, but a reflective liquid crystal display module having no backlight, and an organic EL display module other than the liquid crystal display module. Needless to say, the present invention is widely applied to various other FPD modules.

It is typical sectional drawing which shows the liquid crystal display module as one Embodiment of this invention. It is the perspective view which decomposed | disassembled and showed a part of said liquid crystal display module. (A) is a top view which shows the said liquid crystal display module, (b) is the side view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame case 11 Shelves 12, 14 (Frame) Short side plate 13, 15 (Frame) Long side plate 16 Locking protrusion 17 Stopper surface 2 Liquid crystal display panel 21, 22 Front, rear glass substrate 23, 24 Front, rear polarizing plate 3 Driver chip 4 Main FPC (Flexible Printed Circuit)
5 Double-sided adhesive sheet 6 Surface emitting backlight unit 61 Light guide plate 62 LED (Light-Emitting Diode)
63 Optical sheet laminate 64 Light reflection sheet 7 Drive control circuit board 8 Connector 9 Shield case 91 Bottom plate 92 (Case) Short side plate 92, 93 (Case) Long side plate 95 Rectangular hole

Claims (3)

A display panel;
A frame formed using a resin material and supporting the display panel;
A shield case comprising an elastic material having a smaller coefficient of thermal expansion than that of the frame, and having a U-shaped cross-section that collectively clamps at least one end of the display panel and a corresponding end of the frame by elastic force; A display module characterized by that.   The display module according to claim 1, wherein the shield case is formed by processing a thin stainless plate.   In the display module, a liquid crystal display panel, a surface emitting irradiation panel, and a drive control circuit board that controls driving of the entire module are arranged at predetermined positions via a frame, and the liquid crystal display panel, the surface emitting irradiation panel, and the drive control are arranged. The display module according to claim 1, wherein the display module is a liquid crystal display module that is connected to a circuit board by a flexible wiring board and is housed and held in the shield case together with the frame.

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