Device for maintaining alignment between a focal point of a laser beam and a slit aperture

摘要

An optical wedge compensates for a vertically drifting laser beam in response to ambient temperature fluctuations. A slit sensor is formed onto a surface of the wedge to separate a single light pulse from a plurality of light pulses. A reflective filter layer is applied to a side opposite the slit sensor so an incident laser beam is attenuated thereby precluding damage to the slit sensor. The reflective filter coating further filters out unwanted light energy. The wedge is shaped so as to maintain a position of a focal point of a laser beam on the slit sensor and to prevent reflected light from damaging a laser source.