An optical element surface monitoring system includes an optical beam shaper and an optical sensor. The optical beam shaper directs an input beam of light from a laser source onto a surface portion of an optical element. The optical sensor receives a reflected beam of light from the optical element,...http://www.google.fr/patents/US6046802?utm_source=gb-gplus-shareBrevet US6046802 - Optical element surface monitoring system and method
Optical element surface monitoring system and method
