SPURIOUS ELECTROMAGNETIC ENERGY DISCRIMINATOR FOR ELECTRO-OPTICAL INSPECTION SYSTEMS

摘要

An electro-optical system for inspecting an object includes a source producing a beam of electromagnetic energy, for example, a laser. It also includes a means for discriminating between electromagnetic energy of the beam scattered from objects within a predetermined distance of a plane intersected by the beam of electromagnetic energy and electromagnetic energy not so scattered. Thus, spurious electromagnetic energy scatteed by other objects near the inspected object are ignored.