Method and system for determining interferometric optical path l

Details Method and system for determining interferometric optical path l Method and system for determining interferometric optical path l

1978-06-05

1980-09-30

Evans, F. L.

Optics: measuring and testing

By polarized light examination

With birefringent element

G01B 902

Patent

active

042252407

ABSTRACT:
A method and system for determining interferometric optical path length difference including: varying the interferometric optical path length difference between a first and a second surface in three steps at one-quarter wavelength intervals; sensing the intensity of the interferogram radiation at at least one position of the interferogram at each of the steps; storing the intensity sensed at each position at each step; for each of the positions adding the intensity of the first and third steps to produce a d.c. spatial frequency amplitude, subtracting the intensity of the third step from that of the first to obtain the cosinusoidal spatial frequency amplitude, and subtracting the intensity of the second step from the d.c. amplitude to produce the sinusoidal spatial frequency amplitude; combining the sinusoidal and cosinusoidal amplitudes to produce a trigonometric function of the phase angle of the radiation reflected from each position of the first and second surfaces and generating from the trigonometric function of the phase angle an output representative of the optical path length difference at each position.

REFERENCES:
patent: 3694088 (1972-09-01), Gallagher et al.
patent: 3950103 (1976-04-01), Schmidt-Weinmar
patent: 4022532 (1977-05-01), Montagnino

Affiliated with

Also associated with

Rating

Method and system for determining interferometric optical path l does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and system for determining interferometric optical path l, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and system for determining interferometric optical path l will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1166905