IP Library Granted Patent US 7,855,761
Granted Patent B2
US 7,855,761 · App. 12/230,912 · Granted Dec 21, 2010

Liquid crystal display device

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Quick Facts
Patent No.
US 7,855,761
App. No.
12/230,912
Granted
Dec 21, 2010
Kind
B2
Abstract

In a liquid crystal display device which uses light emitting diodes as a light source, a backlight can efficiently house a heat radiation plate even when an area of the heat radiation plate is increased by taking the radiation of heat from the light emitting diodes into consideration. Light emitting diodes are arranged on a metal substrate to form a plate-shaped light source portion. A heat radiation effect is enhanced by adhering a heat radiation plate to the plate-shaped light source portion. The heat radiation plate to which the plate-shaped light source is adhered is constituted as a housing casing thus efficiently housing the heat radiation plate. A problem which occurs due to the use of the metal-made housing casing can be overcome by mounting a resin-made light guide plate fixing member on the housing casing.

Claims (23)

1. A liquid crystal display device comprising:

a display panel;

a backlight which radiates light to the display panel;

a plurality of light emitting elements mounted on the backlight;

a printed circuit board on which the light emitting elements are arranged;

a light guide plate on which light emitted from the light emitting elements is incident;

a housing casing which houses the light guide plate therein, the housing casing being made of metal and having a bottom surface and a first side surface and a second side surface which are folded to intersect the bottom surface, wherein the printed circuit board is arranged on the first side surface, and a resin member for fixing the light guide plate is formed on a mounting portion of the second side surface at a position where the second side surface intersects with a first side surface of the light guide plate.

2. A liquid crystal display device according to claim 1 , wherein the light emitting element is an LED.

3. A liquid crystal display device according to claim 1 , wherein a cutout portion is formed in the second side surface, and the resin member is fitted in the cutout portion.

4. A liquid crystal display device according to claim 1 , wherein the printed circuit board is constituted by mounting a flexible printed circuit board on a metal plate.

5. A liquid crystal display panel comprising:

a liquid crystal panel;

a planar light source device which radiates light to the liquid crystal panel;

light emitting diodes which are arranged linearly in the inside of the planar light source device;

a printed circuit board which electrically connects the light emitting diodes;

a light guide plate which has an incident surface on which light emitted from the light emitting diodes is incident; and

a metal-made housing portion which houses the light guide plate therein, wherein

the metal-made housing portion includes a side surface which faces the incident surface in an opposed manner,

the printed circuit board is arranged on the side surface which faces the incident surface, and

a resin member for fixing the light guide plate to keep a distance between the light guide plate and the printed circuit board is mounted on a mounting portion of the metal-made housing portion.

6. A liquid crystal display device according to claim 5 , wherein an optical sheet is stacked on the light guide plate, and the resin member holds the optical sheet.

7. A liquid crystal display device according to claim 5 , wherein the resin member is fitted in the metal-made housing portion.

8. A liquid crystal display device according to claim 5 , wherein the printed circuit board is constituted by mounting a flexible printed circuit board on a metal plate.

Assignments (9)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 10, 2025
From: JAPAN DISPLAY INC
To: MAGNOLIA PURPLE CORPORATION
Reel/Frame 071890/0202 →
CHANGE OF NAME Recorded Nov 17, 2023
From: HITACHI DISPLAYS, LTD.
To: JAPAN DISPLAY EAST, INC.
Reel/Frame 065614/0223 →
CHANGE OF NAME Recorded Nov 17, 2023
From: JAPAN DISPLAY EAST, INC.
To: JAPAN DISPLAY, INC.
Reel/Frame 065614/0644 →
CHANGE OF ADDRESS Recorded Nov 17, 2023
From: JAPAN DISPLAY, INC.
To: JAPAN DISPLAY, INC.
Reel/Frame 065654/0250 →
NUNC PRO TUNC ASSIGNMENT Recorded Nov 17, 2023
From: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
To: PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA
Reel/Frame 065615/0327 →
MERGER Recorded Dec 13, 2011
From: IPS ALPHA SUPPORT CO., LTD.
To: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
Reel/Frame 027482/0140 →
ATTACHED ARE (1) THE COMPANY SPLIT DOCUMENTS IN JAPANESE WITH ENGLISH TRANSLATION THEREOF AND (2) THE CERTIFICATE OF COMPANY SPLIT DOCUMENT IN JAPANESE WITH ENGLISH TRANSLATION, WHICH TOGETHER CONVEY 50% OWNERSHIP OF THE REGISTERED PATENTS AS LISTED IN THE ATTACHED TO EACH OF THE RECEIVING PARTIES (SEE PAGE 10, EXHIBIT 2-1, SECTION 1 OF THE ENGLISH TRANSLATION OF THE COMPANY SPLIT PLAN.) Recorded Dec 13, 2011
From: HITACHI, DISPLAYS, LTD.
To: HITACHI DISPLAYS, LTD.; IPS ALPHA SUPPORT CO., LTD.
Reel/Frame 027615/0589 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 4, 2011
From: HITACHI DISPLAY DEVICES, LTD.
To: HITACHI DISPLAYS, LTD.
Reel/Frame 026223/0293 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 8, 2008
From: WATANABE, SABURO; TOKUYAMA, HIROSHI
To: HITACHI DISPLAYS, LTD.; HITACHI DISPLAY DEVICES, LTD.
Reel/Frame 021549/0146 →