Background compensating interferometer
AssigneeUniversity of Arizona Foundation
InventorsHenry A. Hill, John W. Figoski, Paul T. Ballard
Life of this patent
Estimating the term…
Abstract
A device for reducing the effects of scattered light in an optical instrument utilizes an interferometer for interfering the scattered light and placing the image of the desired object within a dark fringe of the scattered light interference pattern to increase the contrast between the image of the desired object and the background.
Claims12
An optical phase shifter for adjusting the relative phase of two beams of light while maintaining the relative phase substantially constant over a broad range of frequencies comprising:
- a first phase shifter comprising a first sheet of optically transparent material having a first thickness and a first index of refraction that varies as a function of wavelength disposed along the path of said first light beam and operative to shift the phase thereof;
- and
- a second phase shifter comprising a second sheet of optically transparent material having a second thickness and a second index of refraction that varies as a function of wavelength in a manner other than that of the first index of refraction disposed along the path of said second light beam and operative to shift the phase thereof, said thicknesses and said indices of refraction being selected in a predetermined manner for maintaining the phase difference between said first and second light beams substantially constant over a predetermined range of frequencies.
A phase shifter for adjusting the relative phase of two beams while maintaining the relative phase substantially constant over a broad range of frequencies comprising:
- a first phase shifter comprising a first sheet of material substantially transparent to the first beam having a first thickness and a first index of refraction that varies as a function of wavelength disposed along the path of said first beam and operative to shift the phase thereof;
- and
- a second phase shifter comprising a second sheet of material transparent to the second beam having a second thickness and a second index of refraction that varies as a function of wavelength in a manner other than that of the first index of refraction disposed along the path of said second beam and operative to shift the phase thereof, said thicknesses and said indices of refraction being selected in a predetermined manner for maintaining the phase difference between said first and second beams substantially constant over a predetermined range of frequencies.
Dependencies are inferred from the claim text.