A method and
system for high-speed, high-resolution, 3-D imaging of an object including an anamorphic
magnification and field lens
system to deliver the light reflected from the object to a small area
position detector having a position-sensing direction. Preferably, an acousto-optic deflector together with associated lens elements scans a beam of modulated
laser light across the object to produce a telecentric, flat field scan. The deflector has a
feedback loop to enable uniform illumination of the object. The light scattered from the object is collected by a telecentric
receiver lens. A combined spatial and polarization filtering plane preferably in the form of a programmable
mask is provided to control the polarization and acceptance angles of the collected light. A reduction or focusing lens is positioned immediately behind the filtering plane and is utilized as a
telescope objective. The lens
system includes a negative cylinder lens having a relatively large
focal length and a field lens having a relatively small
focal length. The cylinder lens and the reduction lens magnify the image in the position sensing direction of the
detector and the field lens delivers the magnified light to the
detector. The
detector is a
photodetector such as a lateral effect
photodiode or a rectangular lateral effect detector. A pre-
amplifier provides a pair of electrical signals which are utilized by
signal processing circuitry to compute the
centroid of the
light spot.