Wideband diffractive optical element, has gratings incorporated in respective gradient-index materials that are arranged in phase-locked relation to each other

摘要

The diffractive optical element comprises at least two combined optical gratings. A first gradient-index grating with a phase characteristic P3 (lambda, z) is incorporated into a first gradient-index material (3) with a dispersion characteristic n3 (z, lambda). A second gradient-index grating with a phase characteristic P4 (lambda, z) is incorporated into a second gradient-index material (4) with a dispersion characteristic n4 (z, lambda). Both gradient-index materials (3,4) are arranged in a phase-locked relation to each other.