SELECTIVE DIFFRACTIVE OPTICAL ELEMENT AND A SYSTEM INCLUDING THE SAME

摘要

A selective diffractive optical element includes a first diffractive region having a first design on a first surface of a substrate, and a second diffractive regio having a second design on the first surface of the substrate, the first and second designs being different, wherein, by altering a position of a cross - section of an illumination beam, the selective diffractive optical element outputs a desired combination of the two diffraction patterns.