Liquid crystal display heating system

• US 4,987,289 A
• Filed: 07/21/1988
• Issued: 01/22/1991
• Est. Priority Date: 07/21/1988
• Status: Expired due to Term

• Current Assignee: Rockwell International Corporation
• Original Assignee: Rockwell International Corporation
• Inventors: Bishop, Gary D., Campbell, Melvin L., Shaw, James E.
• Primary Examiner(s): Evans, Geoffrey S.
• Application Number:
  US07/223,204
• Time in Patent Office: 915 Days
• Field of Search: 219/209, 219/210, 219/528, 219/541, 219/543, 219/549, 350/351, 350/331 T
• US Class Current: 219/209
• 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

Abstract

A non-uniform heating system is provided for liquid crystal displays. The system includes structure for applying a greater concentration of heat to the periphery of LCDs. Because mounting structures produce large heat sinks around the edges of LCDs, providing greater heat to the edges results in a more uniform distribution of heat across the LCDs. In another aspect of the heating system, rapid warming may be provided for preselected critical areas of a display to reduce warm-up time, reduce power consumption, and provide mission critical displays in situations such as scrambles of military aircraft on cold weather alert.

Claims

1. A heater for a liquid crystal display (LCD), comprising:

a thin film conductor applied to an LCD;

power supply means connected to said LCD for providing an electrical potential across said thin film conductor; and

a plurality of electrical connectors attached to said thin film conductor at its corner edges for directing electrical current through said thin film conductor so as to provide greater heating near the edges of the LCD.

2. A heater for a liquid crystal display (LCD), comprising:

a thin film conductor applied to an LCD;

power supply means connected to said LCD for providing an electrical potential across said thin film conductor; and

a plurality of discontinuities in said thin film conductor for directing electrical current through said thin film conductor so as to provide greater heating near the edges of the LCD.

3. A heater for a liquid crystal display (LCD), comprising:

a thin film conductor applied to an LCD;

power supply means connected to said LCD for providing an electrical potential across said thin film conductor;

means for directing electrical current through said thin film conductor so as to provide greater heating near the edges of the LCD; and

means for providing heat to preselected critical areas of the LCD for rapid warm-up of said critical areas during start-up of the LCD.

4. A system for providing non-uniform heating of a liquid crystal display (LCD), comprising:

a thin film conductor applied to an LCD;

power supply means coupled to said LCD for providing an electrical potential across the thin film conductor; and

means for directing electrical power to preselected critical areas of the LCD for rapid warm-up of said critical areas during start-up of the LCD.

5. The LCD heating system of claim 4, wherein said power directing means comprises a fixed geometry for said thin film conductor.

6. The LCD heating system of claim 4, wherein said electrical power directing means comprises a plurality of electrical connectors attached to the thin film conductor at the edges corner of the LCD.

7. The LCD heating system of claim 4, further comprising:

a sensor for sensing the temperature of said critical areas; and

said power directing means comprising a microprocessor that receives an input from said sensor.