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:
May. 07, 1996
Filed:
May. 28, 1993
United Technologies Corporation, Hartford, CT (US);
Abstract
A remote active multipoint fiber laser sensor includes a plurality of fiber lasers 12,14,16, each having a pair of Bragg gratings 18,20, embedded in a fiber 10 and excited by a common pump light 30. The lasers 12,14,16 lase at different longitudinal modes (lasing wavelengths) and emit light 32,34,36, at their respective wavelengths .lambda.1,.lambda.2,.lambda.n. The lasing wavelength of each laser shifts due to perturbations, such as strain or temperature, applied thereto. The output light 32,34,36 is fed to a spectrum analyzer 50 where the wavelength shift is analyzed. A signal processor 54 reads the wavelength shift and provides a signal on lines 56 indicative of the perturbation at each of the lasers/sensors 12-16. Alternatively, a single laser may be used as a single sensor. Alternatively, birefringent fiber may be used as the fiber cavities 21 and the two polarizations are beat together to form a lower difference or 'beat' frequency, thereby allowing lower frequency detection devices to be used.