Compact, high performance, scanning heterodyne optical interferometers for interferometric phase-based measurement and a host of other applications are introduced. An in-line, almost common-path optical interferometer design offers robustness to externally induced phase noise via mechanical vibrations, thermal effects, and other environmental effects. Several instrument designs are disclosed for both transmissive and reflective interferometry. These interferometers use acousto-optic devices or Bragg cells to implement rapid (e.g., <50 >.mu.s/scan spot) optical scanning of a test medium. Although the read optical beam scans a given test region, the double Bragg diffraction optical design of the instrument makes the final interfering output beams stationary on the two high speed photo-detectors used for radio frequency signal generation via heterodyne detection. One photo detector acts as the fixed phase reference, while another fixed photo detector picks up the test medium phase informat
Application Serial Number
Assignee at Issuance
College of Optics and Photonics
Assignee at Filing
Nonprovisional Application Record
Riza, Nabeel, "Scanning heterodyne Acousto-optical interferometers" (1997). UCF Patents. 501.