Title:
METHOD FOR ADJUSTING BACK-LIGHT LUMINANCE OF LIQUID CRYSTAL
Document Type and Number:
Japanese Patent JPH01227131
Kind Code:
A
Abstract:
PURPOSE:To maintain an excellent displaying quality suitable for an ambient temperature by measuring the temperature in an apparatus and changing the luminance of the back-light of liquid crystal in accordance with the temperature. CONSTITUTION:Since the resistance value of a thermistor 4 changes when the temperature inside an apparatus main body changes, the frequency of a signal line 5 changes in accordance with the temperature inside the main body and, as a result, the temperature inside the main body can be recognized. The luminance of the back-light of liquid crystal is changed in accordance with the recognized temperature. When, for example, the temperature inside the main body is low, a transistor 9 is turned on through a signal line 8. Then the voltage value of a power source 7 for driving a cold cathode-ray tube type fluorescent lamp 20 can be boosted and, as a result, the luminance of the lamp 20 can be raised. Thus excellent luminance is obtained even when the temperature is low and, at the same time, the time until an excellent displaying quality is obtained can be shortened.
Inventors:
NAKAMURA AKIYOSHI
Application Number:
JP5440888A
Publication Date:
September 11, 1989
Filing Date:
March 08, 1988
Export Citation:
Assignee:
SEIKO EPSON CORP
International Classes:
G02F1/133; G09F9/00; (IPC1-7): G02F1/133; G09F9/00
Attorney, Agent or Firm:
Mogami (1 person outside)