Patent ID: 6742707
Filing Date: 2004-06-01
Classification: B82Y,G02B,G06K,H01S

Abstract:
A method of reducing speckle-pattern noise at the image detection array of a planar laser illumination and imaging (PLIIM) based system, said method comprising the steps of:(a) producing a planar laser illumination laser beam (PLIB) within a planar laser illumination and imaging (PLIIM) based system including an image detection array having image forming optics with a field of view (FOV) arranged in a coplanar relationship with said PLIB; (b) reducing the spatial-coherence of said PLIB before said PLIB illuminates a target object, by applying a spatial phase shifting technique during the transmission of said PLIB towards the target, so that the object is illuminated with a spatially coherent-reduced planar laser illumination beam (PLIB) and numerous substantially different time-varying speckle-noise patterns are produced at said image detection array over the photo-integration time period thereof; (c) detecting said numerous substantially different time-varying speckle-noise patterns over said photo-integration time period; and (d) temporally averaging said detected speckle-noise patterns at said image detection array during said photo-integration time period thereof, thereby reducing the power of observable speckle-noise patterns at said image detection array.