Liquid Crystal Display Device

• US 20080088763A1
• Filed: 10/02/2007
• Published: 04/17/2008
• Est. Priority Date: 10/02/2006
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Watanabe, Saburo, Fukayama, Norihisa, Toriyama, Yoshio
• Granted Patent: US 8,009,244 B2
• Time in Patent Office: Days
• US Class Current: 349/58
• CPC Class Codes: G02B 6/0083 Details of electrical connections of light sources to drivers, circuit boards, or the like
• CPC Class Codes: G02B 6/0091 of the light source relative to the light guide G02B6/0021 takes precedence

Abstract

Plural light-emitting diodes are disposed in an on-line arrangement on a surface a circuit board facing an optical guide and spacers having a projecting dimension larger than the projecting dimension of this light-emitting diode from the surface are disposed adjacent to the light-emitting diode on the surface of the circuit board.

Claims

1. A liquid crystal display device, comprising:

a liquid crystal display panel formed by enclosing a liquid crystal layer between a pair of transparent substrates having a pixel-forming electrode on an inner surface; and

a backlight for irradiating an illumination light on the liquid crystal display panel,

wherein the backlight includes;

plural light-emitting elements;

a circuit board on which these plural light-emitting elements are disposed;

an optical guide facing the light-emitting elements disposed on the circuit board at a predetermined interval therefrom; and

a case housing the circuit board and optical guide,

wherein a spacer which prevents the optical guide from coming in contact with the light-emitting elements is disposed between the optical guide and the circuit board.

2. The liquid crystal display device according to claim 1,

wherein the spacer is disposed on the circuit board.

3. The liquid crystal display device according to claim 2,

wherein the projecting dimensions of the spacer from the circuit board surface are larger than the projecting dimensions of the light-emitting elements from the circuit board surface.

4. The liquid crystal display device according to claim 1,

wherein the spacer is a sheet-like body interposed between the circuit board and the optical guide, and the sheet-like body has openings at positions corresponding to the light-emitting elements.

5. The liquid crystal display device according to claim 4,

wherein the openings are respectively disposed corresponding to the light-emitting elements.

6. The liquid crystal display device according to claim 1,

wherein the spacer is disposed on the optical guide.

7. The liquid crystal display device according to claim 6,

wherein the projecting dimensions of the spacer from the optical guide surface are larger than the projecting dimensions of the light-emitting elements from the circuit board surface.

8. The liquid crystal display device according to claim 1,

wherein the case has:

a flat part on which the optical guide is mounted;

a side wall standing substantially perpendicular to the flat part which supports the circuit board; and

a depression which is disposed between this side wall and the flat part, the depression housing the lower part of the circuit board and being set back substantially parallel to the side wall from the edge of the flat part.

9. The liquid crystal display device according to claim 1,

wherein the circuit board is stuck to the case.

10. The liquid crystal display device according to claim 1,

wherein the circuit board has a leg extending substantially parallel to the side wall of the case from its lower edge, this leg being inserted into the opening of the depression in the case and fixed to the case.

11. The liquid crystal display device according to claim 1,

wherein the spacer has a projection extending further downwards from the lower edge position of the circuit board, this projection being inserted into the opening of the depression in the case and fixed to the case.

12. The liquid crystal display device according to claim 1,

wherein the spacer has an inverted needle projecting towards the sidewall of the case in part of the projecting part, this inverted needle engaging with a notch in the lower part of the circuit board and fixed to the circuit board.