Method of testing aspherical optical surfaces with an interferometer

US5416586A · kind A · utility

Assignee

• Tropel Corporation · US

Inventors

• Mark Joseph Tronolone · Fairport, US
• Jon Fleig · Rochester, US
• Chunsheng Huang · San Jose, US
• John H. Bruning · Pittsford, US

Key dates

• Filing date: Oct 15, 1993
• Grant date: May 16, 1995
• Expiry date: Oct 15, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B11/255
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A Fizeau interferometer (10) producing spherical test and reference wavefronts (34 and 36) is operated with a linear translator (50) for making a sequence of subaperture measurements of an aspherical test surface (40). Separate phase maps (88 and 90) are assembled at different focus positions (54 and 56) along a common optical axis (52) of the interferometer (10) and aspherical test surface (40). Respective null zones (92 and 94) are isolated from the phase maps (88 and 90) and are combined to form a composite phase map (100) defining differences between the aspherical test surface (40) and a family of spheres.