| 摘要 |
When any application can be operated, a control section first indexes a table for defining validness or invalidness of an operating key corresponding to an application in a memory. Then, if the control section detects that any key is operated, the control section starts to turn ON a back light. Thereafter, the control section detects that any key is manipulated again before a lighting time set by a timer elapses, and it is decided whether the operation section is a valid key. If the valid key is operated, a first back light for illuminating the most neighboring part of the valid key and a second back light for illuminating a display section are continuously turned ON until the lighting time set by the timer of the control section elapses. However, if the lighting time set by the timer of the control section elapses, the back light is turned OFF. <IMAGE> |
