By the use of a Combo-DOE it is possible to get the absolute deviations of an aspherical surface. A light source of the NIR region is used to allow the measurement of steep aspherics.
© 2004 Optical Society of America
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(120.4290) Instrumentation, measurement, and metrology : Nondestructive testing
F. Simon, N. Lindlein, and J. Schwider, "Test of aspherics in the NIR with a diffractive optical element as null lens," in Frontiers in Optics 2004/Laser Science XXII/Diffractive Optics and Micro-Optics/Optical Fabrication and Testing, OSA Technical Digest (Optical Society of America, 2004), paper XWA3.