| 摘要 |
PROBLEM TO BE SOLVED: To obtain a laser beam output device which is stopped from outputting laser beams without using an exclusive optical system when the connector of an optical fiber is dismounted or the optical fiber is disconnected. SOLUTION: Laser beams 36 outputted from a laser diode 31 are made incident on an optical fiber 42 connected to an optical connector 43 but also on a photodiode 32 to control the laser diode 31 in output so as to be kept constant in output power through a power monitor circuit 37 and a current drive circuit 33. If the optical fiber 42 is disconnected or the optical connector 43 is dismounted, returned light are detected by the photodiode 32, and the trouble is detected by a connection discriminating circuit 41 basing on the detection output 39 of the power monitor circuit 37. The current drive circuit 33 stops the laser diode 31 from outputting the laser beams 36 basing on the detected signal 45 of the connection discriminating circuit 41, and the laser diode 31 is kept at a light emission level of an LED. |
