Holographic Notch Filter for Low-Wavenumber Stokes and Anti-Stokes Raman Spectroscopy

Abstract
A holographic notch filter with a 15-nm rejection band is used as a Rayleigh line filter for Raman spectroscopy with a single-stage grating spectrograph. The filter is shown to allow acquisition of Stokes and anti-Stokes spectra as close as 72 cm−1 from the exciting line.