Scratch and Defect Measurement

Abstract

The stringent performance requirements of a number of systems involving optics and electronics in, for example, mass information storage, high power laser optics, aspheric surface generation, integrated optics and solid state circuitry, have tended in recent years to accentuate the need for rigorous control of surface quality. The effect of a surface imperfection, such as a scratch or dig or even surface contamination, can be either cosmetic, as would be the case with a spectacle lens or the front component of a camera lens, or functional if it resulted in a reduction in the useful life or power output (1) of, say, a high power laser system or reduced the yield of devices produced from a semi-conductor wafer.