Fig. 3
From: Scalable miniature on-chip Fourier transform spectrometer for Raman spectroscopy
Characterization results of the multi-aperture waveguide-based Fourier transform spectrometer. a Camera image of the vertical grating coupler’s outputs and the corresponding output power of the interferometers. b Measured and numerically calculated interferometer responses versus wavelength, both normalized by their respective maximum values between 805 nm and 880 nm. c Free spectral range of each interferometer, averaged over the wavelength range. d Transform matrix of the Fourier transform spectrometer, showing the response of all interferometers within the characterized wavelength range
