Phase shifting diffraction interferometer

Patent · Thu Aug 29 04:00:00 EDT 1996

OSTI ID:372585

Sommargren, G E

An interferometer which has the capability of measuring optical elements and systems with an accuracy of {lambda}/1000 where {lambda} is the wavelength of visible light. Whereas current interferometers employ a reference surface, which inherently limits the accuracy of the measurement to about {lambda}/50, this interferometer uses an essentially perfect spherical reference wavefront generated by the fundamental process of diffraction. This interferometer is adjustable to give unity fringe visibility, which maximizes the signal-to-noise, and has the means to introduce a controlled prescribed relative phase shift between the reference wavefront and the wavefront from the optics under test, which permits analysis of the interference fringe pattern using standard phase extraction algorithms. 8 figs.

• Research Organization: University of California
• DOE Contract Number: W-7405-ENG-48
• Assignee: Univ. of California, Oakland, CA (United States)
• Patent Number(s): US 5,548,403/A/
• Application Number: PAN: 8-345,878
• OSTI ID: 372585
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
DATA ANALYSIS
DESIGN
INTERFEROMETERS
OPTICAL SYSTEMS
SIGNAL-TO-NOISE RATIO
VISIBLE RADIATION