| 摘要 |
PROBLEM TO BE SOLVED: To provide a light emission device in which the precision of determination as to whether an excessive voltage is applied to LED or not is suppressed from being reduced.SOLUTION: A light emission device has LED 10, a switch 20 connected to LED in parallel, voltage applying portions 30, 40, 50 for applying voltages to LEDs, and a controller 80 for monitoring the voltages applied to LEDs and controlling the voltages output from the voltage applying units on the basis of a monitoring result to detect short-circuit and wire breaking, thereby controlling the driving state of the switch. In the controller, the voltage amount based on a voltage drop due to flow of current through LEDs of p for which short-circuit or wire breaking is detected is subtracted from a determination voltage for determining whether the voltages applied to light emission targets LED are excessive or not. On the basis of the thus-calculated new determination voltage, the controller determines whether voltages applied to LEDs obtained by excluding the LEDs of p from light emission targets are excessive or not.SELECTED DRAWING: Figure 1 |
