Liquid crystal display device with common heater between two cells

• US 5,247,374 A
• Filed: 04/01/1991
• Issued: 09/21/1993
• Est. Priority Date: 04/05/1990
• Status: Expired due to Fees

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Terada, Toshiyki
• Primary Examiner(s): Howell, Janice A.
• Assistant Examiner(s): GROSS, ANITA P
• Application Number:
  US07/678,609
• Time in Patent Office: 904 Days
• Field of Search: 359/44, 359/53, 359/43, 359/86
• US Class Current: 349/161
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
• CPC Class Codes: G02F 1/1397 the twist being substantially higher than 90°, e.g. STN-, SBE-, OMI-LC cells

Abstract

A double-layered type while/black super-twisted liquid crystal display device including a driving cell and a compensating cell in a layered structure wherein a substrate having no optical anisotropy is interposed between the driving cell and the compensating cell and a heater is arranged on the substrate is disclosed. The heater is composed of two electric conductive films, one of them being deposited on one surface of the substrate and the other one being deposited on the opposite surface of the same. In addition, a liquid crystal display device of the foregoing type wherein a heater comprising a single electric conductive thin film is interposed between the driving cell and the compensating cell is disclosed. Each thin film constituting the heater is deposited by employing a vaporizing process. Alternatively, each thin film constituting the heater may be deposited by employing a spattering process.

Claims

1. A layered white and black super-twisted nematic liquid crystal display device comprising:

a driving cell and a compensating cell formed in a layered structure;

a substrate having no optical anisotropy, said substrate having first and second surfaces, and substrate being interposed between said driving cell and said compensating cell;

a common heater arranged on said substrate for heating both said driving cell and said compensating cell, said common heater including first and second electrically conductive thin films; and

said first thin film being formed on said first surface of said substrate and said second thin film being formed on said second surface of the substrate.

2. The liquid crystal display device according to claim 1, wherein at least one of said first and second thin films comprises a vapor deposited film.

3. The liquid crystal display device according to claim 1, wherein at least one of said first and second thin film comprises a sputtered film.

4. The liquid crystal display device according to claim 1, wherein said driving cell is positioned on a side of said substrate that faces an illumination light source and said compensating cell is positioned on a side of said substrate that faces an observer.

5. The liquid crystal display device according to claim 1, wherein said driving cell is positioned on a side of said substrate that faces an observer and the compensating cell is positioned on a side of said substrate that faces an illuminating light source.

6. A layered type white and black super-twisted nematic liquid crystal display device comprising:

a driving cell and a compensating cell formed in a layered structure;

a common heater interposed between said driving cell and said compensating cell for simultaneously heating both said driving cell and said compensating cell; and

wherein said heater comprises a single electrically conductive thin film.

7. The liquid crystal display device according to claim 6, wherein said single thin film is formed on an inner surface of said driving cell that faces an illuminating light source.

8. The liquid crystal display device according to claim 6, wherein said single thin film is formed on an inner surface of said compensating cell that faces an observer.

9. The liquid crystal display device according to claim 6, wherein said thin film comprises a vapor deposited film.

10. The liquid crystal display device according to claim 6, wherein said thin film heater comprises a material sputtered on a surface of at least one of said driving cell and said compensating cell.