Optical scanner feedback system having a reflected cylinder lens

摘要

An optical scanner feedback system. The feedback system provides a feedback signal representative of a laser beam focused along an optical path onto a scanning surface. The feedback system includes a cylinder lens having a longitudinal axis and a transverse axis, located along the optical path having an optical surface for shaping and focusing the laser beam in a first direction. A photodetector is provided having an active region sensitive to light. The laser beam includes a scanning portion which passes through the lens and a reflected portion which reflects off the lens. The reflected portion is reflected such that it is incident on the photodetector active region for providing an output signal representative of the laser beam.