Invention Grant
- Patent Title: Synchronous frequency-shift mechanism in fizeau interferometer
- Patent Title (中): fizeau干涉仪中的同步变频机构
-
Application No.: US12701535Application Date: 2010-02-06
-
Publication No.: US08345258B2Publication Date: 2013-01-01
- Inventor: James E. Millerd , Michael North-Morris
- Applicant: James E. Millerd , Michael North-Morris
- Applicant Address: US AZ Tucson
- Assignee: 4 D Technology Corporation
- Current Assignee: 4 D Technology Corporation
- Current Assignee Address: US AZ Tucson
- Agent Antonio R. Durando
- Main IPC: G01B9/02
- IPC: G01B9/02

Abstract:
An optical device for characterizing a test surface combines a Fizeau interferometer with a polarization frequency-shifting element. Two substantially collinear, orthogonally polarized beams having respective frequencies differing by a predetermined frequency shift are generated by the polarization frequency-shifting element and projected into the Fizeau optical cavity to produce a pair of test beams and a pair of reference beams, wherein the beams in each pair have orthogonal polarization states and have frequencies differing by the predetermined frequency shift. A second, substantially equal frequency shift is introduced in the Fizeau cavity on either one of the pairs of test and reference beams, thereby generating a four-beam collinear output that produces an interferogram without tilt or short-coherence light. The invention may also be implemented by reversing the order of the Fizeau cavity and the polarization frequency-shifting element in the optical train.
Public/Granted literature
- US20100134801A1 SYNCHRONOUS FREQUENCY-SHIFT MECHANISM IN FIZEAU INTERFEROMETER Public/Granted day:2010-06-03
Information query