| 摘要 |
<p>PROBLEM TO BE SOLVED: To resolve a problem that, although a lightening and extinguishing switch is required to be provided at an LED side when an illuminating device using an LED as a light-emitting source is configured so that a lighting power supply and the LED are provided separately and both are connected by a lead wire, in a case where this lightening and extinguishing switch is provided in series to the LED, an applied voltage is raised rapidly immediately after the lightening and extinguishing switch is turned off, and when the lightening and extinguishing switch is turned on again before the voltage is reduced, a rush current flows in the LED, and the life of the LED is deteriorated.SOLUTION: A detection resistor is provided at an anode side. A voltage dividing resistor that is in series to the detection resistor is provided at a lighting power supply side. By short-circuiting the detection resistor by a lightening and extinguishing switch, turn-on of the lightening and extinguishing switch can be detected at the lighting power supply side.</p> |
