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:
Apr. 18, 2000
Filed:
Apr. 14, 1998
John D Prohaska, Torrance, CA (US);
Lothar U Kempen, Redondo Beach, CA (US);
Robert A Lieberman, Torrance, CA (US);
Physical Optics Corporation, Torrance, CA (US);
Abstract
A method of determining the wavelength of light transmitted in an optical fiber comprises the steps of filtering the light using a filter, and then detecting the filtered light, and then determining the wavelength of the filtered light. The filter comprises a fiber grating which is recorded in a portion of the optical fiber. The fiber grating preferably has a modulated index of refraction with a modulation amplitude that varies from a first end to a second end of the fiber grating, and a modulation period defined by a grating constant that varies from the first end to the second end of the fiber grating. The fiber grating at least partially prevents transmission of light within a wavelength spectrum, and prevents transmission of a substantially larger portion of the light at a first end of the wavelength spectrum than at a second end of the wavelength spectrum. Therefore, the wavelength of the filtered light can be determined by determining a proportion of the light which was transmitted by the filter. The proportion of light which is transmitted by the filter is preferably linearly related to the wavelength of the light.