DIFFRACTION-LIMITED HOLOGRAPHIC LENSES IN DICHROMATED GELATIN

Holographic lenses in volume media suffer from the mismatch between th e recording and the reconstruction wavelength. The lenses are recorded in the blue spectral range because of spectral sensitivity of the rec ording material. The lenses investigated here are reconstructed with r ed light. The aim of this work is the realization of diffraction-limit ed holographic lenses with a high diffraction efficiency in the presen ce of a wavelength mismatch. Therefore the lenses have to be recorded with at least one aspheric recording wavefront in order to fulfill the Bragg condition on the one hand and to correct the wave aberrations o n the other. We propose an iterative optimization procedure which also eliminates the wave aberrations caused by the misalignments or the re cording setup. This optimization procedure requires the accurate measu rement of the wave aberrations. These aberrations are eliminated by an appropriate modification of the aspheric recording wavefront. In this paper the design principle, the recording setup, the interferometric measurement, and the iterative optimization procedure are given, This optimization procedure results in diffraction-limited holographic lens es. (C) 1996 Society of Photo-Optical Instrumentation Engineers.