Laser beam scan enhancement through periodic aperture transfer.
A new approach to laser beam scanning is introduced which is sufficiently general to be applied to a wide variety of techniques. Periodic scan enhancement is described as a method of taking advantage of iteration or summation of contributions from individual scanning sections without imposing the progressive increase in aperture size. Vignetting at the scanning aperture is avoided, permitting employment of a multiplicity of elements whose sizes are diffraction limited. This is achieved by the interposition of alternate lenticular elements which reimage the aperture of one scanning element upon the aperture of the next. Thus, the responsibility of increased aperture size as scan progresses is transferred from the (dynamic) scanning element itself to the (static) transfer optics. Several examples illustrate application of this technique. Over-all optics is considered to approach diffraction-limited performance with minimum loss.
Beiser
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CBS Laboratories, High Ridge Road,Stamford, Connecticut 06905, USA.