| 摘要 |
<p>An apparatus for measuring the reflectivities of the resonator facets of a semiconductor laser when the facets are covered with a protective coating of dielectric material or the like, which comprises photodetector means for individually measuring the laser light powers from both facets of the resonator, reflector means for reflecting the laser light from one of the facets back to the laser, shutter means openable or closable at a position to block the laser light reflected from the reflector means, and photodetector means for measuring the power of the reflected laser light.</p> |
