| 摘要 |
PURPOSE:To enable the automatic output control not only at constant-current drive, but also at even at high-frequency pulse drive by controlling the driving current by temperature detection so as to obtain a constant light output constantly. CONSTITUTION:A temperature of a laser diode 24 is detected by a temperature detector 23 and the detected temperature signal is read by a microcomputer 26. If the temperature is over the upper limit or is under the lower limit, a reset switch 27 operates to stop the current flowing to a laser diode 24 instantly. Also, the temperature signal from the temperature detector 23 is between the upper and lower limits, a current control signal corresponding to that temperature is outputted and a drive current generator 29 supplys a drive current to the laser diode 24. When a switch 21 is turned on, the microcomputer 26 starts the operation to take in the temperature signal. Next, when a switch 22 is turned on, the current control signal is outputted to cause the drive current generator 29 to flow the drive current to the laser diode 24. |
