Reference system for optical devices including optical scanners and spectrum analyzers

摘要

A reference system for an optical wavelength scanner, used for measuring wavelengths of radiation from an optical device. The system utilizes a wavelength reference comprising a fixed fiber Fabry-Perot (FFP) filter in combination with a reference fiber Bragg grating (FBG) of accurately known wavelength to minimize the effects of drift and nonlinearities in the scanner. The system utilizes dual optical branches, one containing a device or devices which generate, emit or reflect light of a particular wavelength which is to be measured or identified and the other containing the reference. The two branches are periodically illuminated, while the wavelength band is scanned for peaks or notches in light intensity in the illuminated branch. The wavelengths, at which peaks or notches in the light intensity of each branch occur, are logged. The wavelengths of the reference comb of the fixed FFP are determined by reference to that of the reference FBG. Then, the peaks or notches in the light intensity from the device under test are located by interpolation with respect to the comb of peaks produced by the reference.