Asphere testing with a Fizeau interferometer based on a combined computer-generated hologram.
Fizeau interferometers with an additional diffractive optical element are frequently used for measuring spherical and aspherical surfaces. We present a new (to our knowledge) optical test method, in which the Fizeau principle is now perfectly fulfilled by generating reference and measuring wavefront on the last optical surface, which carries a diffractive optical element. This method has been examined experimentally by testing a reference f/0.68 spherical mirror and can be applied identically for testing aspheres. Several advantages of this method are discussed and proved experimentally.
Asfour
Jean-Michel
JM
Dioptic GmbH, Kriemhildstrasse 11, 69469 Weinheim, Germany. Asfour@dioptic.de
Poleshchuk
Alexander G
AG