| 摘要 |
PURPOSE:To provide an output control device for use in output control of a light source in varieties of optical players such as CDs (Compact Disc) and LDs (Laser Disc), the device being capable of accurately and properly controlling an output from such an LD. CONSTITUTION:Laser lights emitted from a front exit surface and from a rear exit surface are detected by front detector means 2 and by rear detector means 3, respectively, an output from a semiconductor laser 1 is controlled on the basis of a detection signal from the front detector means 2 and a detection signal S2 from the rear detector means 3 is compared with a detection signal S1. from the forward detector means 2 by comparator means 4. Alarm means 5 alarms on the output control of the semiconductor laser 1 based upon a comparison signal S3 as a comparison result. Hereby, backward light is prevented from affecting the output control and erroneous output control due to condensation or contamination on an incident surface in the forward detector means is successfully monitored to accurately and properly control the output from the semiconductor laser. |
