Cross-axis cascading of spectral dispersion

Abstract

We demonstrate a method of cascading multiple diffractive elements for improving the purity of spectral dispersion, The cross-axis cascade was implemented in a two-stage grating spectrograph, resulting in a hundredfold reduction of stray light and a high dynamic range up to -75 dB. The technique can be used for parallel spectral measurements and processing. (C) 2008 Optical Society of America