FOCUSING ELEMENTS AND SYSTEM FOR PRODUCING A PRESCRIBED ENERGY DISTRIBUTION ALONG AN AXIAL FOCAL ZONE

摘要

FOCUSING ELEMENTS AND SYSTEM FOR PRODUCING A PRESCRIBED ENERGY DISTRIBUTION ALONG AN AXIAL FOCAL ZONE The focusing system includes a source of light having an axially symmetric intensity distribution and a lens designed to focus such light into a focal zone with a specified intensity distribution along the zone. This distribution is preferably uniform so as to provide the detector with a modulated light beam of uniform average intensity regardless of the position of the record along to focal zone. The lens is but one member of an entire family of nonconical, aspherical axicon-type focusing elements designed in accordance with a method described herein to focus energy from given source to a prescribed focal zone intensity distribution.