| 摘要 |
<p>PURPOSE:To provide a semiconductor laser capable of outputting photoelectric current for monitoring optical output and capable of providing great optical output by forming a reflecting film on the end face of a main chip from which a main beam is not led out and arranging a photosensor in front of the end face radiating the main beam while deviating the photosensor from the main axis. CONSTITUTION:A semiconductor laser chip 10 used herein has a reflecting film 7 provided on the opposite end face to a main beam 202 so that optical output is taken out only from the direction of the main beam. A PIN photodiode as a monitoring photosensor 120 is arranged in front of the end face of the semiconductor laser chip 10 from which the main beam is led out, while deviated from the main axis. A part 206 of the optical output is applied to the photosensor 120 and photoelectric current corresponding to the optical output of the semiconductor laser is taken out of the semiconductor laser through an external lead terminal 104. Drive circuit of the semiconductor laser is controlled according to the photoelectric current so that the optical output is held constant. In this manner, it is possible to provide a semiconductor laser capable of providing great optical output and of monitoring the optical output.</p> |
