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:
Oct. 23, 1990
Filed:
Nov. 23, 1988
Raymond W Huggins, Mercer Island, WA (US);
The Boeing Company, Seattle, WA (US);
Abstract
An optical sensor and an optical sensing system and method in which both analog and digital techniques are employed. The sensor comprises an encoder and an illumination source. The encoder includes a plurality of tracks, and the illumination source illuminates each track with an associated optical input signal. Each input signal comprises light in a wavelength range different from the wavelength ranges of the other input signals. Each track includes means responsive to the value of a measurand for modulating the intensity of the associated input signal, in one of N different ways, to produce a corresponding modulated signal, N being greater than 2. The intensities of the modulated signals thereby encode the value of the measurand. The illumination source may also produce a reference signal that is not modulated by the measurand. The modulated and referenced signal may be combined into an output signal, and the composite input signal and output signals may be conveyed to and from the sensor via fiber-optic cables.