| 摘要 |
<p>PURPOSE:To enable monitoring of laser rays even if a polarity changes on a monitoring side by a method wherein a monitoring photodetector composed of two photodiodes is constructed in a back-to-back structure. CONSTITUTION:A copper heat sink 2 is fixed to a central part of the upper face of a rectangular copper stem 1 through a brazing material. A laser diode 4 is fixed to a side face of the heat sink 2 through the intermediary of a sub- mount 3. Laser rays 5 are emitted from both the top and the bottom end of the diode 4. A monitoring photodetector 9 is fixed to the primary face of the stem 1. The photodetector 9 receives the laser rays 5 and serves as a monitoring element which detects an optical output. The element 9 is composed of two photodiodes which are built monolithically in a back-to-back structure. Therefore, the element 9 can detect laser rays even if the impressed voltage changes in polarity.</p> |
