Patent ID: 6825922
Filing Date: 2004-11-30
Classification: G01B,G01S

Abstract:
A system for high-precision determination of the angular position of a light beam in an optical scanning device, the system comprising:a source of light that emits a substantially collimated primary light beam; a light-sensitive sensor; an optical element used to focus an image onto the sensor; and a rotatable mirror system that re-directs the primary light beam to a plurality of locations of an external surface of a component, the rotatable mirror system comprising: a rotary axis; a mirror structure that rotates about the rotary axis; at least one detector positioned to intercept a light beam that has been reflected off the mirror structure at an angle representing a start-of-scan such that a first trigger pulse is generated, and positioned to intercept a light beam that has been reflected off the mirror structure at an angle representing an end-of-scan such that a second trigger pulse is generated; and an auxiliary system that provides measurement data between the start-of-scan angle and the end-of-scan angle; wherein the first trigger pulse and the measurement data are used to determine the angular position of the primary light beam.