Patent ID: 7199874

Claim:
A surface inspection apparatus comprising: an illumination source for directing a light beam onto a workpiece to generate a scattered light pattern having a spatial distribution that includes light scattered into a first spatial domain in accordance with the ordinary scattering pattern of the workpiece and light scattered into a second spatial domain associated with light scattered from defects of the workpiece; a refractive optical element for capturing a portion of the light scattered from the surface; a first light detection element capable of receiving light from the refractive element and capturing a two-dimensional image of the light and translating the two-dimensional image into an electrical signal; a first programmable light selection array arranged to receive the scattered light captured by the refractive optical element, wherein the first programmable light selection array includes an array of controllable light selection elements that can be selectively enabled to revent light in the second spatial domain associated with the ordinary scattering pattern of the workpiece from being received by the first light detection element; a reflective optical element for capturing scattered from the surface; a second light detection element capable of receiving light from the reflective element and capturing a two-dimensional image of the light and translating the two-dimensional image into an electrical signal; a second programmable light selection array arranged to receive the scattered light captured by the reflective optical element, wherein the second programmable light selection array includes an array of controllable light selection element, that can be selectively enabled to prevent light in the second spatial domain associated with the ordinary scattering pattern of the workpiece from being received by the second light detection element; processing circuitry for receiving the electrical signals from the first and second light detection elements and using it to conduct surface analysis of the workpiece.