| 摘要 |
PROBLEM TO BE SOLVED: To prevent a liq. crystal display panel from being damaged by avoiding a surplus temp. raise even if generating abnormality in a temp. sensor in a backlight of a liq. crystal display device used in an environment severely varying mainly in a temp. condition. SOLUTION: When power supply to a cold cathode tube 12 is started, the power corresponding to the temp. is supplied to the cold cathode tube 12 by the temp. raise caused by the heat generation of a lamp by a temp. sensor 14, in the case that the temp. rising cannot be detected even if the power is supplied to the cold cathode tube 12, that the temp. sensor 14 gets out of order or a short circuit with dew condensation is considered. In this case, the power supplied to the cold cathode tube 12 is limited in a preliminarily fixed value. |
