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:
Mar. 01, 1994
Filed:
Dec. 13, 1991
William K Burns, Alexandria, VA (US);
Robert P Moeller, Ft. Washington, MD (US);
Marta M Howerton, Bowie, MD (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
An apparatus comprised of a depolarized light source for fiber optic sensors is disclosed. In a preferred embodiment, the depolarized light source of the apparatus comprises: a first laser for generating a first beam at a first frequency, the first beam having a linear polarization state; a second laser for generating a second beam at a second frequency, the second beam having a linear polarization state; a means for rotating the polarization state of the second beam so that the first and second beams have orthogonal linear polarization states with respect to each other; and a means for combining the first beam with the polarization-rotated second beam to obtain a composite beam which is depolarized. In a system operation, the apparatus comprises: a source of depolarized light; an integrated optic modulator means for receiving a modulator drive signal; a first low-birefringence fiber for conveying the depolarized light beam from the depolarized light source to the integrated optic modulator means, the integrated optic modulator means modulating only one linear polarization state in the depolarized light beam as a function of the modulator drive signal to produce a modulated beam; a photodetector; and a second low-birefringence fiber for conveying the modulated light beam to the photodetector, the photodetector being responsive to the modulated light beam for developing an electrical signal proportional to the modulator drive signal.