Liquid-crystal display device with a gasket for controlling thermal gradient within the device

• US 6,330,045 B1
• Filed: 02/14/2000
• Issued: 12/11/2001
• Est. Priority Date: 02/16/1999
• Status: Expired due to Fees

• Current Assignee: Vista Peak Ventures LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: NEC Corporation
• Inventors: Tanaka, Hideki
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US09/503,951
• Time in Patent Office: 666 Days
• Field of Search: 349/58-60
• US Class Current: 349/58
• CPC Class Codes: G02F 1/133385 with cooling means, e.g. fans

Abstract

In a liquid-crystal display device comprising a liquid-crystal display panel, a light source provided in proximity to the liquid-crystal display panel for illuminating the liquid-crystal display panel, a transformer of the light source provided in proximity to the liquid-crystal display panel, and an enclosure for housing the liquid-crystal display panel, the light source and the transformer, a gasket is provided between the liquid-crystal display panel and the enclosure for controlling a thermal gradient of the liquid-crystal display panel.

Claims

1. A liquid-crystal display device comprising:

a liquid-crystal display panel;

a light source provided in proximity to said liquid-crystal display panel for illuminating said liquid-crystal display panel;

a transformer of said light source provided in proximity to said liquid-crystal display panel; and

an enclosure for housing said liquid-crystal display panel, said light source and said transformer;

wherein a gasket having a size approximately the same as the transformer is provided between said liquid-crystal display panel and said enclosure for controlling a thermal gradient of said liquid-crystal display panel.

2. A liquid-crystal display device according to claim 1, wherein said gasket is disposed in proximity to said light source.

3. A liquid-crystal display device according to claim 1, wherein said gasket is made of a foam material with resilience and covered with an electrically conductive material.

4. A liquid-crystal display device according to claim 1, wherein said gasket is adhered to a rear surface of the liquid display panel.

5. A liquid-crystal display device comprising:

a liquid-crystal display panel;

a light source provided in proximity to said liquid-crystal display panel for illuminating said liquid-crystal display panel;

a transformer of said light source provided in proximity to said liquid-crystal display panel; and

an enclosure for housing said liquid-crystal display panel, said light source and said transformer;

wherein a gasket is provided between said liquid-crystal display panel and said enclosure for controlling a thermal gradient of said liquid-crystal display panel, wherein a thermal capacity of said gasket satisfies the following relationship;

$\frac{Q_4^{\mathrm{\prime <br><br>}}}{\frac{<br><br>T_4}{<br><br>t}}<<br><br>C_4\leqq <br><br>\frac{\int <br><br>\left(Q_2-Q_4+Q_4^{\mathrm{\prime <br><br>}}\right)<br><br><br><br>t}{\int <br><br>\frac{<br><br>T_4}{<br><br>t}<br><br>\text{\hspace{1em}<br><br>}<br><br><br><br>t}$

where C₄ is the thermal capacity of said enclosure, Q₂ is a heat flow between an air layer in said enclosure and said liquid-crystal display panel, Q₄ is a heat flow between said gasket and said enclosure, Q′

₄ is a heat flow between said gasket and an air layer in said enclosure, and T₄ is a temperature of said gasket.

6. A liquid-crystal display device according to claim 5, wherein said gasket is disposed in proximity to said light source.

7. A liquid-crystal display device according to claim 5, wherein said gasket is made of a foam material with resilience and covered with an electrically conductive material.

8. A liquid-crystal display device according to claim 5, wherein said gasket is adhered to a rear surface of the liquid display panel.

9. A liquid-crystal display device according to claim 5, wherein said gasket has a size approximately the same as the transformer.

10. A liquid-crystal display device comprising:

a liquid-crystal display panel;

a light source provided in proximity to said liquid-crystal display panel for illuminating said liquid-crystal display panel;

a transformer of said light source provided in proximity to said liquid-crystal display panel; and

an enclosure for housing said liquid-crystal display panel, said light source and said transformer;

wherein a gasket, made of a foam material with resilience and covered with an electrically conductive material, is provided between said liquid-crystal display panel and said enclosure for controlling a thermal gradient of said liquid-crystal display panel.

11. A liquid-crystal display device according to claim 10, wherein said gasket is disposed in proximity to said light source.

12. A liquid-crystal display device according to claim 10, wherein a thermal capacity of said gasket satisfies the following relationship:

$\frac{Q_4^{\mathrm{\prime <br><br>}}}{\frac{<br><br>T_4}{<br><br>t}}<<br><br>C_4\leqq <br><br>\frac{\int <br><br>\left(Q_2-Q_4+Q_4^{\mathrm{\prime <br><br>}}\right)<br><br><br><br>t}{\int <br><br>\frac{<br><br>T_4}{<br><br>t}<br><br>\text{\hspace{1em}<br><br>}<br><br><br><br>t}$

where C₄ is the thermal capacity of said enclosure, Q₂ is a heat flow between an air layer in said enclosure and said liquid-crystal display panel, Q₄ is a heat flow between said gasket and said enclosure, Q′

₄ is a heat flow between said gasket and an air layer in said enclosure, and T₄ is a temperature of said gasket.

13. A liquid-crystal display device according to claim 10, wherein said gasket is adhered to a rear surface of the liquid display panel.

14. A liquid-crystal display device according to claim 10, wherein said gasket has a size approximately the same as the transformer.