Birefringence of CuGa2S4 crystals

Abstract

Investigation of the spectral characteristics as a function of the crystal thickness demonstrates that one can create filters using thin crystals for selecting several spectral lines. The wavelength of these lines is situated on the short wavelength side of the λ0. One can control the number of these lines by changing the crystal thickness. These devices are comb filters with definite wavelengths. For a wider use of the elaborated narrow band filters in Raman spectroscopy and other optical spectroscopy experiments, it is necessary to employ the wavelengths of the filter transmission bands to correspond to the emission lines of the lasers.