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. 12, 1991
Filed:
Mar. 17, 1989
Raymond W Huggins, Mercer Island, WA (US);
The Boeing Company, Seattle, WA (US);
Abstract
An optical WDM sensor and sensing system for determining a value of a measurand, such as an encoder position. An optical source produces a composite input signal that includes a plurality of different wavelength component signals. The sensor includes an encoder and a concave diffraction grating. The encoder has a plurality of tracks, each track being responsive to the value of the measurand for modulating the intensity of light incident thereon to produce a modulated signal. The grating demultiplexes the composite input signal to produce separate component signals that are directed to an incident upon the respective tracks. Each track produces a modulated signal, and the modulated signals are multiplexed, preferably by the grating, to produce a return signal that may be demultplexed and detected to determine the measurand value. Preferably, the sensor comprises a planar optical waveguide having the grating formed on one side surface. The encoder may be positioned adjacent to the waveguide, or coupled to the waveguide via optical fibers.