Design of linear variable optical filter-based spectrum analysis system

At present, the better the linear variable optical filter (LVOF) performance, the more difficult its fabrication. In order to address this issue, this study designs a LVOF targeting the solar-blind ultraviolet wavelength region (200–300nm), visible light region (510–700nm), and near-infrared region (800–1050nm) by utilizing the Fabry-Perot resonator principle and the optical transfer matrix method. In the visible spectrum range, the working wavelength band of this filter is 510–700nm, with a peak transmittance exceeding 61%. The ratio of the full width at half maximum (FWHM) to the peak wavelength is 5%, and the linear dispersion coefficient reaches 8.37nm/mm. By combining the visible spectrum linear variable optical filter with a band-pass filter and linear array charge coupled device (CCD), a spectral analysis system is constructed to measure the emission spectrum of the fluorescent glass. The experimental results demonstrate the advantages of our technology in terms of accuracy and efficiency.