| 摘要 |
<p><heading lvl="0">Abstract of Disclosure</heading> A driving unit drives a light emitting unit, so that a light detecting unit detects light output from the light emitting unit, and a detection signal detected by the light detecting unit is transmitted to a controlling unit. When the detection signal from the light detecting unit is transmitted for a predetermined amount of time or more, the controlling unit stops a driving operation of the light emitting unit, which is performed by the driving unit, and protects the light emitting unit from being destroyed due to an overcurrent.</p> |
