Dual-wave-front computer-generated holograms for quasi-absolute testing of aspherics.
Testing of aspherics by means of computer-generated holograms (CGHs) is well known. To perform a quasi-absolute test of rotationally symmetric aspheric surfaces, two wave fronts must be encoded in the CGH. Both the null lens and a spherical lens have to be stored. This enables successive measurements of the aspheric and of a cat's-eye position without changing the object arm of the interferometer. Two possibilities for encoding both wave fronts have been investigated. A first-order approximation for estimating the influence of disturbing diffraction orders is given.
Beyerlein
Mathias
M
Physikalisches Institut, Lehrstuhl für Optik, Universität Erlangen-Nürnberg, Germany. beyerlein@optik.uni-erlangen.de
Lindlein
Norbert
N
Schwider
Johannes
J