Fourier transform micro spectrometer based on spatially-shifted interferogram bursts

摘要

A spectrometer with improved resolution includes a spectral domain modulator having a periodic response in the spectral domain to modulate a wideband source spectrum and cause one or more shifted bursts in the interferogram.

主权项

1. A spectrometer, comprising:
a primary interferometer including at least one moveable element, the primary interferometer optically coupled to receive a wideband source spectrum and operable to direct the wideband source spectrum along an optical path so as to produce an interference pattern; an actuator coupled to the at least one moveable element to cause a displacement of the at least one moveable element to vary the optical path; an optical detector optically coupled to detect an interferogram produced as a result of the interference pattern and the displacement of the at least one moveable element; a spectral domain modulator including an auxiliary interferometer coupled to the primary interferometer and having a periodic response in the spectral domain to modulate the wideband source spectrum, the spectral domain modulator operable to cause one or more shifted bursts in the interferogram, a number of shifted bursts and an amount of shift in each of the shifted bursts being determined based on the periodic response of the spectral domain modulator; and processing circuitry coupled to the optical detector to receive the interferogram including the one or more shifted bursts, the processing circuitry configured to:
determine a measured spectrum using a mathematical transform of the interferogram;calibrate motion of the at least one moveable element to produce a corrected spectrum from the measured spectrum; andminimize harmonics in the corrected spectrum caused by the spectral domain modulator; wherein the auxiliary interferometer and the primary interferometer are Fabry-Perot interferometers; wherein the auxiliary interferometer is formed within a first dielectric portion between a first surface and a second surface of the first dielectric portion, the second surface being opposite the first surface; wherein the primary interferometer is formed in air between the second surface of the first dielectric portion and a third surface of a second dielectric portion, the second dielectric portion being separate from the first dielectric portion; wherein the first dielectric portion and the second dielectric portion each include a respective piece of dielectric material and each of the first dielectric portion and the second dielectric portion are separate from other optical components in the optical path.