Microroughness-blind optical scattering instrument

摘要

A microroughness-blind optical scanner focuses p-polarized light onto the surface of a sample. Scattered light is collected through independently rotatable polarizers by one or more collection systems uniformly distributed over a hemispherical shell centered over the sample. The polarizer associated with each collection system is rotated to cancel the corresponding Jones vector thereby preventing detection of microroughness-scattered light, yielding higher sensitivity to particulate defects. The sample is supported on a positioning system permitting the beam to be scanned over the sample surface of interest.