| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve visibility of a display lamp when it becomes hard to see as a situation of surroundings changes. <P>SOLUTION: A detection part 13 to detect the situation of the surroundings and a control part 11 to drive and control a plurality of LED light sources 1 are installed. At a usual time, the control part 11 drives only one part of the plurality of LED light sources 1. When a situation detector 14 detects occurrence of abnormality such as a fire, the detection part 13 detects an abnormal time different from the situation at the usual time based on output of the situation detector 14. When the abnormal time is detected, so as to be brighter in the abnormal time than at the usual time, the control part 11 increases the number of the LED light sources 1 driven at the abnormal time than that of the LED light sources 1 driven at the usual time. <P>COPYRIGHT: (C)2010,JPO&INPIT |
