Patent ID: 6888627
Filing Date: 2005-05-03
Classification: G01N

Abstract:
1. An optical scanning system for detection of anomalies on a surface comprising: optics directing a focused beam of radiation onto a sample surface to produce an illuminated spot thereon; one or more sensors; one or more optical elements, each element collecting radiation scattered from the illuminated spot on the surface along a channel away from a specular reflection direction of the beam and directing the collected and scattered radiation to one of the sensors, causing each of the sensors to provide output signals in response thereto; a detector; and a device causing relative motion between the beam and the surface so that the beam is caused to illuminate different parts of the surface and so that the sensors and the detector provide output signals in response to radiation from different parts of the surface illuminated by the beam, said detector performing time delayed integration on signals provided in response to radiation from the illuminated spot on the surface in synchronism with the relative motion to provide output signals.