Abstract: A system and method for errant laser beam detection are provided for effectively detecting small coating failures in a cost effective and robust manner. In one embodiment, a detection system includes a continuity circuit on a printed circuit board (PCB) having metal (e.g., copper) traces which are designed to burn through if an errant beam strikes them. The traces are sized and patterned appropriately to sense a minimum subaperture size.

Abstract: A system and method for errant laser beam detection are provided for effectively detecting small coating failures in a cost effective and robust manner. In one embodiment, a detection system includes a continuity circuit on a printed circuit board (PCB) having metal (e.g., copper) traces which are designed to burn through if an errant beam strikes them. The traces are sized and patterned appropriately to sense a minimum subaperture size.

Abstract: A method for interferometrically determining error continuously in the radius of curvature of a planetary polishing surface and for providing compensating correction of the surface shape while the polishing machine is in operation. A conditioner glass body disposed on the polishing surface for reshaping the surface is itself a Fizeau cavity having upper and lower partially-reflective surfaces which are parallel or slightly non-parallel for plano polishing and spherical polishing. The conditioner is illuminated by a plano, monochromatic, coherent light wavefront substantially perpendicular to the polishing surface, preferably over the entire upper surface of the conditioner. A portion of the incident wavefront is reflected from the upper surface as a reference wavefront, and another portion of the incident wavefront is reflected from the lower surface as a measurement wavefront.