HYPERBOLIC HOLOGRAPHIC GRATINGS - ANALYSIS AND INTERFEROMETRIC TESTS

The aberrations of hyperbolic diffraction gratings produced with two s pherical waves are analyzed theoretically and experimentally. The beha vior of these gratings in collimated illumination indicates that for a grating of a given size there is a critical spatial frequency above w hich the aberration remains constant for all spatial frequencies. Aber rations associated with geometrical errors in the recording geometry a re derived. With simple interferometric tests, misalignments in the re cording process can be identified easily.