Patent ID: 6327036
Filing Date: 2001-12-04
Classification: G01D,G01J,G02B

Abstract:
A multi-wavelength measurement system for measurement of one or more wavelengths in an input optical signal which comprises:(a) a Fiber Bragg Grating which reflects a known Bragg wavelength;(b) an inteferometer which transmits a comb of reference;(c) a reference light source;(d) a scanner comprising a tunable filter having a control voltage signal for tuning the wavelength of the filter;(e) a light detector; and(f) an optical splitter providing:(1) in a measurement operating state selective optical coupling of input optical signal sequentially to the Fiber Bragg Grating, the tunable filter of the scanner, and the light detector or(2) in a reference operating state selective optical coupling of reference light from the reference light source into the Fiber Bragg Grating and reference light from the reference light source into the interferometer and optically coupling of the reflected Bragg wavelength of the Fiber Bragg Grating and the comb of wavelengths of the Fiber Bragg Grating sequentially to the tunable filter of the scanner and the light dectector;wherein in the reference operating state the scanner applies the control signal to the tunable filter causing it to scan across the wavelength spectrum of the tunable filter so that the reference wavelengths of light form the Fiber Bragg Grating and the interferometer passing through the tunable filter are detected by the detector and related to the control signal; andwherein in the measurement operating state the scanner applies the control signal to the tunable filter causing it to scan across the wavelength spectrum of the tunable filter so that the wavelengths of light in the input optical signal passing through the tunable filter are detected by the light detector and related to the control signal and thereby related to the reference wavelengths to determine the wavelengths of light in the input optical signal.