| 摘要 |
PROBLEM TO BE SOLVED: To provide a light emission control device capable of preventing an IGBT from being broken down even while controlling flat light emission. SOLUTION: This is a flat light emission control device provided with an IGBT for controlling light emission of a xenon tube, a light receiving means for receiving the light emitted by the xenon tube and generating an output corresponding to a quantity of the received light, a comparison means for comparing a voltage corresponding to the output of the light receiving means with a prescribed voltage and generating an output corresponding to the comparison result, a latching means for inputting the output of the comparison means thereto and holding the input state as an output, a flat light emission control means for switching on-off the IGBT by the output of the latching means and holding light emission intensity of the xenon tube almost at a constant level by letting the on-off switching repeat for a prescribed period, a switching means for lying between the comparison means and the latching means, and a switching control means for holding the switching means to be off-state for a prescribed period when the output of the latching means changes, and letting the latching means hold the output regardless of the changes in the output of the comparison means until the prescribed time has passed, to inhibit the on-off changeover of the IGBT. |
