The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 1994
Filed:
Nov. 06, 1992
Joseph A McClintock, Baltimore, MD (US);
Jeffrey P Andrews, Abingdon, MD (US);
Martin Marietta Corporation, Bethesda, MD (US);
Abstract
A method for sensing an environmental parameter includes the step of sensing the environmental parameter with an interferometer sensor that has a light source emitting a tunable wavelength of light and a gap that changes in length in response to the environmental parameter. The interferometer has a sinusoidal output curve that oscillates in intensity in response to changes in gap length. The wavelength of light emitted by the light source is tuned to a first wavelength to provide a first output value. Similarly, the wavelength of light emitted by the light source is next tuned to a second wavelength to provide a second output value. The first and second output values correspond to points on the sinusoidal output curve that differ by at least half a cycle. The gap length is then calculated from the values of the first wavelength and the difference between the first and second wavelengths. Finally, the value of the environmental parameter is determined from the value of the gap length.