Accession Number : ADD013176

Title :   Phase-Modulated Polarizing Interferometer.

Descriptive Note : Patent, Filed 6 Jul 82, patented 6 Nov 84,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Bareket,Noah ; Metheny,Wayne W

Report Date : 06 Nov 1984

Pagination or Media Count : 7

Abstract : An interferometer for measuring optical surfaces is capable of very high sensitivity. A HeNe laser light is converted into a circular polarized beam, spatially filtered and collimated. The light beam is passed through a photoelastic modulator for modulating the relative phase of the two polarization states of the optical field of the beam. The beam is then passed through a ROCHON prism which splits the beam into two orthogonally polarized components. One beam is reflected off the optical surface that is being measured and is recombined with the undeviated beam. The resulting irradiance distribution oscillates in the modulation frequency and the phase of the oscillation is dependent upon the optical path difference between the two beams. The detected interference signal is processed to extract the phase information.

Descriptors :   *PATENTS, *OPTICAL INTERFEROMETERS, *PHASE MODULATION, *POLARIZATION, SURFACES, OPTICAL PROPERTIES, MEASUREMENT, GRAZING, HIGH SENSITIVITY, PHOTOELASTICITY, SIGNAL PROCESSING, HELIUM NEON LASERS

Subject Categories : Meteorology
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE