A well-established solution for measurement of aspheric surfaces relies on translating the test part along the optical axis of a precision laser Fizeau interferometer while collecting interference fringes from areas of low slope relative to a spherical reference surface. The data are assembled into a final surface profile using the instrument geometry and scan history. This principle has been the foundation of a commercial instrument for nearly two decades. Here we report on several key advances for this instrument: 1. Optical configuration management for improved automated alignment for flats, spheres, aspheres, and torics. 2. Upfront and re-callable distortion and magnification calibrations for each transmission sphere/zoom combination. 3. Job-centric user interface with improved ease-of-use, including importing of asphere definitions directly from standard lens design software files. We give an overview of the new system, show measurement examples, and discuss how the improvements mentioned above affect the metrology and the user experience.
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