| 摘要 |
PURPOSE:To extend the lighting time at the rear side of a liquid crystal display element by providing 1st and 2nd lamps to use for lighting for the rear side of the liquid crystal display element and switching the driving to the 2nd lamp when the 1st lamp is faulty. CONSTITUTION:The device is provided with 1st and 2nd lamps 2, 9 lighting the rear side of a liquid crystal display member 1, driving means 11, 13 switching the lamp into the 2nd lamp 9, and driving the 2nd lamp 9 when the 1st lamp is faulty. When the 1st lamp 2 is faulty, for instance, the filament is broken, the driving means 11, 13 lights the 2nd lamp 8, and the lighting for the rear side of the liquid crystal display member 1 is continued. Thus, the lighting time is extended nearly double and no repair by the service man is required for the time and the number of visits by the service man is decreased. |
