JP5523228B2 - Display device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a display device in which a backlight is disposed on the back side of a transmissive display panel, and a method for manufacturing the same.

A liquid crystal panel module (LCD module) includes a backlight that irradiates the LCD panel from the back. In recent years, backlights of LCD modules used in high-quality thin display devices are of a direct type in which light emitting diodes (LEDs) are arranged at substantially equal intervals directly under the LCD panel for the purpose of increasing brightness and reducing brightness unevenness. Structure is adopted. Since a large number of LEDs are arranged in the direct type LED backlight, the power consumption of the LED drive circuit section (driver IC) is increased, and cooling thereof is an important issue. Further, when dust or the like enters the backlight internal space formed between the LCD panel and the LED and light leaks from the space to the outside, it causes display unevenness and luminance reduction. Therefore, a sealed structure with dust and light shielding measures is adopted.
In a conventional LED backlight, an LED board is housed in a casing, and a driver board including a driver IC is attached to the rear surface of the chassis constituting the casing. The electrical connection between the LED board and the driver board is made by a connector and a cable, and for this purpose, an opening slightly larger than the outer shape of the connector is provided in the chassis. By sticking the light-shielding adhesive tape described in Patent Document 1 to this opening, the backlight can be shielded from light and dust-proof. A cooling fan is disposed in the vicinity of the driver board. Patent Document 2 discloses an electronic device having a configuration in which outside air is taken into a housing by driving a fan to cool an electronic component, and dust that has entered the housing as the outside air is taken in is adsorbed by a charging member. .

JP 2009-40901 A JP 2007-65124 A

In the prior art, there is a problem that the configuration for heat dissipation, light shielding and dust prevention is complicated. That is, a light-shielding pressure-sensitive adhesive tape is required as a dust-proof and light-shielding means for the electrical connection portion between the light source of the backlight and the drive circuit unit. In order to cool the drive circuit unit, it is necessary to provide a fan for blowing air.
Accordingly, an object of the present invention is to dissipate heat from a drive circuit unit with a simple structure and to take measures against light shielding and dust prevention related to an electrical connection portion between a light source of a backlight and the drive circuit unit.

A display device according to an embodiment of the present invention is a display device including a display panel and a backlight unit, and the backlight unit includes a first substrate having an illumination light source for the display panel, and the illumination light source. wherein a second substrate having a driving circuit unit for driving and a supporting lifting member you support the first substrate at the first surface, wherein the first surface of the supporting member and the second surface opposite A heat transfer member provided between the second substrate and the second substrate is provided. The first substrate and the second substrate are electrically connected through openings formed in the support member and the heat transfer member, respectively, and the opening of the heat transfer member is blocked by the second substrate. ing.

  According to the present invention, heat dissipation of the drive circuit unit and light shielding and dust prevention of the backlight unit can be realized with a simple structure.

It is a disassembled perspective view which shows the structural example of the LCD module which concerns on 1st Embodiment of this invention. It is a cross-sectional view which shows the structural example of the LCD module which concerns on 1st Embodiment of this invention. It is a cross-sectional view which shows the structural example of the LCD module which concerns on 2nd Embodiment of this invention.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described.
1 and 2 show a structural example of a liquid crystal panel (LCD) module according to the present embodiment. FIG. 1 is an exploded perspective view of an LCD module, with the front side being the upper side of the drawing and the back side being the lower side. FIG. 2 is a cross-sectional view of the LCD module, with the front side being the left side of the figure and the back side being the right side.
The LCD module 1 is provided with an LCD panel 2 as a display panel on the front side, and includes a direct-type backlight unit on the back side. In the backlight internal space, a first substrate (hereinafter referred to as an LED substrate) 4 on which an LED 3 that is a light source for illumination is mounted is disposed. The LED substrate 4 is attached to a first surface on the front side of a plate-like support member (hereinafter referred to as a chassis) 7, and a plurality of LED substrates 4 on which LEDs 3 are mounted at substantially equal intervals are arranged on the chassis.
The LCD panel 2 is held between the front case 5 and the rear case 6. In other words, a rectangular frame front case 5 having a large rectangular opening formed at the center is disposed on the front side of the LCD panel 2, and a large rectangular opening is formed at the center on the back side of the LCD panel 2. A rectangular frame rear case 6 is disposed. Behind the rear case 6 is a plate-like chassis 7 formed of a material having high thermal conductivity (aluminum or the like), and the chassis holds a plurality of LED substrates 4. Although illustration is omitted, optical members such as a diffusion plate and a reflection plate are disposed between the LCD panel 2 and the LED substrate 4.

A second substrate (hereinafter referred to as a driver substrate) 9 having a drive circuit unit for driving the LEDs 3 is disposed on the second surface side (back surface side) of the plate-like chassis 7. A driver IC 8 that drives and controls the LED 3 is mounted on the driver board 9. An inter-board connector 10 for connecting the substrate to the driver substrate 9 is mounted on the surface of the LED substrate 4 opposite to the mounting surface of the LED 3. A connector 11 that fits into the connector 10 is mounted on the driver board 9. That is, the connector 11 mounted on the driver board 9 is a board-to-board connector provided on the surface opposite to the mounting surface of the driver IC 8 for connection with the LED board 4. The LED substrate 4 and the driver substrate 9 are electrically connected by connecting these connectors. A heat transfer member (heat transfer sheet in this example) 12 is provided between the rear surface of the chassis 7 and the driver board 9. The heat transfer sheet 12 is formed of an elastic material (for example, silicone rubber), and a resin foam having a closed cell structure is used.
An opening 7 a is formed in the chassis 7 at a position corresponding to the inter-board connectors 10 and 11. The opening 7 a has an opening diameter larger than the outer shape of these connectors 10 and 11. In the example shown in FIGS. 1 and 2, two sets of board-to-board connectors 10 and 11 arranged almost adjacent to each other are formed so as to be able to penetrate the opening 7a of the chassis. However, the opening 7a of the chassis may be formed so that one set of inter-board connectors 10 and 11 can pass therethrough. In this case, the opening 7a is formed to have an opening diameter slightly larger than the outer shape of the connectors 10 and 11. An opening 12 a is also formed at a position corresponding to the inter-board connectors 10, 11 of the heat transfer sheet 12. The opening 12a of the heat transfer sheet 12 is formed in substantially the same size and position as the opening 7a of the chassis. The board-to-board connectors 10 and 11 are connected through the openings 7a and 12a.

Next, a method for manufacturing the LCD module will be described.
First, the worker arranges the heat transfer sheet 12 at a predetermined position on the back side of the chassis 7. At that time, alignment is performed so that the opening 7a and the opening 12a correspond to each other. Next, the operator fixes the driver board 9 to the chassis 7 by screwing it from the back side of the heat transfer sheet 12. That is, the screw 51 is screwed into the screw hole of the boss 7 b provided in the chassis 7 through the insertion hole of the driver board 9. At this time, the heat transfer sheet 12 having elasticity is sandwiched between the driver substrate 9 and the chassis 7 and is crushed (pressed) to a predetermined thickness. The rear surface of the heat transfer sheet 12 is in close contact with the driver substrate 9, the front surface of the heat transfer sheet 12 is in close contact with the chassis 7, and the heat transfer sheet 12 is fixed between the driver substrate 9 and the chassis 7. Is done. The plurality of inter-board connectors 11 provided on the driver board 9 are disposed inside the opening 7 a of the chassis 7 and the opening 12 a of the heat transfer sheet 12.
Next, the worker attaches the plurality of LED boards 4 from the front side of the chassis 7. That is, the inter-board connectors 10 provided on the LED board 4 are connected to the corresponding inter-board connectors 11, and the LED board 4 is fastened and fixed to the chassis 7 with the screws 50. The assembly completed in the process so far is referred to as a backlight unit 20 below.
Next, the operator attaches the backlight unit 20 to the LCD panel unit. The LCD panel portion is an assembly in which the LCD panel 2 is sandwiched and fixed between the front case 5 and the rear case 6. The LCD panel unit and the backlight unit 20 are fixed with screws 52. That is, the operator inserts the screw 52 into the hole formed in the chassis 7 and screws it into the screw hole of the rear case 6 to complete the assembly of the LCD module 1. The screws 50 to 52, the boss 7b, and the screw holes function as fixing members for fixing the members to each other.

  Note that the opening 12a of the heat transfer sheet 12 and the opening 7a of the chassis do not necessarily have the same shape, and need not necessarily have the same number. The board-to-board connectors 10 and 11 only need to be able to pass through the opening 12a of the heat transfer sheet 12 and the opening 7a of the chassis. 1 shows an example in which three openings 12a of the heat transfer sheet 12 and three openings 7a of the chassis are formed, but the number may be more or less than three. Moreover, the heat transfer sheet 12 is not limited to the shape having the opening 12a, and may have a structure in which a plurality of rectangular heat transfer sheets are arranged so that the inter-board connectors 10 and 11 can be connected. Good. Moreover, although the example which has six LED boards 4 was shown, it may be more or less than six. Further, there may be two or more driver boards 9.

According to the first embodiment, with respect to the backlight internal space formed by the LCD panel 2, the rear case 6, and the chassis 7, the chassis 7 has an opening 7 a for connecting the LED board 4 and the driver board 9. Is formed. A heat transfer sheet 12 having an opening 12 a having the same shape as the opening 7 a is disposed on the back side of the chassis 7, and the heat transfer sheet 12 is pressed by the driver substrate 9 from the back. With the above configuration, heat generated by the driver IC 8 mounted on the driver board 9 can be transmitted to the chassis 7 by the heat transfer sheet 12. That is, the chassis 7 functions as a heat sink. Further, the light shielding and dustproofing for the opening 7a of the chassis 7 can be performed without providing a separate member. That is, in the present embodiment, the backlight internal space can be sealed by the driver substrate 9.
Thus, heat dissipation, light shielding, and dustproofing of the LCD module 1 are realized with a simple structure.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 3 is a cross-sectional view illustrating a configuration example of the LCD module according to the second embodiment. The outline of the configuration according to the present embodiment is the same as that of the first embodiment. Therefore, different parts will be described below, and the same parts as those described above will be omitted by using the same reference numerals already used.
A photometric sensor 30 is mounted on the driver board 9 on the side opposite to the mounting surface of the driver IC 8. The photometric sensor 30 measures the luminance or color in the backlight unit 20. The photometric result is sent to a signal processing circuit (not shown), and is used to drive and control the LED 3 to a desired luminance or color by the driver IC 8. The photometric sensor 30 is mounted on the driver board 9 so that the detection direction faces the display panel side, that is, the front side. In the chassis 7 and the heat transfer sheet 12, openings 7c and 12b are formed at positions facing the photometric sensor 30, respectively. The mounting position of the photometric sensor 30 is a position corresponding to the gap between the LED substrates 4 or a position corresponding to the opening when an opening (not shown) is provided in the LED substrate 4.

  According to the second embodiment, a photometric opening 7 c is formed in the chassis 7 with respect to the backlight internal space formed by the LCD panel 2, the rear case 6, and the chassis 7. A heat transfer sheet 12 having an opening 12 b having the same shape as the opening 7 c is disposed on the back side of the chassis 7, and the heat transfer sheet 12 is pressed against the back of the chassis 7 by the driver substrate 9. With the above configuration, the heat generated by the driver IC 8 mounted on the driver board 9 can be transmitted from the heat transfer sheet 12 to the chassis 7. Moreover, the backlight internal space can be sealed by closing the opening 7c of the chassis 7 with the driver board 9.

1 LCD module 2 LCD panel 3 LED (light source for illumination)
4 LED board (first board)
7 Chassis (supporting member)
7a, 7c Opening 8 Driver IC (Drive circuit)
9 Driver board (second board)
10, 11 Inter-board connector 12 Heat transfer sheet 12a, 12b Opening 20 Backlight 30 Photometric sensor

Claims (8)

A display device including a display panel and a backlight unit,
The backlight unit is
A first substrate having a light source for illumination of the display panel;
A second substrate having a drive circuit unit for driving the illumination light source;
And supporting lifting member you support the first substrate at the first surface,
A heat transfer member provided between the second substrate opposite to the first surface of the support member and the second substrate;
The first substrate and the second substrate are electrically connected through openings formed in the support member and the heat transfer member, respectively, and the opening of the heat transfer member is blocked by the second substrate. A display device. The support member and the second substrate are fixed by a fixing member,
The display device according to claim 1, wherein the heat transfer member is formed of an elastic material and is pressed by the second substrate and the support member.   The photometric means is provided on the surface of the second substrate on the display panel side, and the support member and the heat transfer member have openings at positions corresponding to the photometric means. 2. The display device according to 2.   The connector provided on the first substrate and the connector provided on the second substrate are connected through openings formed in the support member and the heat transfer member, respectively. The display device according to any one of the above. The second substrate seals the inside of the backlight unit by closing the opening of the heat transfer member.
The display device according to claim 1, wherein the display device is a display device. The display device according to claim 1, wherein a plurality of openings are formed in each of the support member and the heat transfer member. The display device according to claim 1, wherein the backlight unit includes a plurality of first substrates. With a display panel and backlight,
The backlight unit is
A first substrate having a light source for illumination of the display panel;
A second substrate having a drive circuit unit for driving the illumination light source;
And supporting lifting member you support the first substrate at the first surface,
A method of manufacturing a display device having a heat transfer member provided between a second surface of the support member opposite to the first surface and the second substrate,
Sandwiching the heat transfer member between the second surface of the support member and the second substrate, and fixing the second substrate to the support member;
The first substrate is fixed to the support member, and the backlight unit is assembled by electrically connecting the first substrate and the second substrate through openings formed in the support member and the heat transfer member, respectively. Process,
A method for manufacturing a display device, comprising a step of fixing the backlight unit and the display panel.

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