Fizeau interferometer for aspheric surfaces
Intellium™ Asphere ESDI Engineering Synthesis Design

The Intellium™ Asphere Fizeau interferometer provides fast, non-contact high-resolution measurement of aspheric surfaces. Our new patent pending Computer Generated Reference™ (CGR™) technology combined with Native sub-Nyquist sampling provides wavefront measurements of aspherical optical components and assemblies such as optical pick-up lenses, cell phone camera optics, and contact lenses. The Asphere uses IntelliWave™, the de-facto standard interferometry software for device-independent interferogram analysis.
Our 2nd generation Intellium™ Asphere is an enhanced Fizeau interferometer incorporating sub-Nyquist and traditional phase-shifting measurement techniques to accurately measure aspheric surfaces. Since the Intellium™ Asphere utilizes standard spherical reference surfaces to measure an aspheric surface, the test and reference beams are no longer common path. ESDI's patent pending asphere technology performs automatic non-common path calibration by generating a Computer Generated Reference™ (CGR™). The CGR™ is derived from the optical prescription of the interferometer measurement system and the surface being measured. It is then combined (Moiré fringes), in real-time, with actual video fringes which results in nulled interferograms, similar to those generated from standard spherical measurements. The user then utilizes these fringes to quickly and accurately align the aspheric surface being tested. Finally, after data acquisition, the CGR is subtracted automatically from the acquired data to give the actual OPD difference relative to the asphere design prescription.