Broadband phase-sensitive CARS spectroscopy by using a combination of edge filters

Abstract

Vibrational Raman spectrum is useful for identification molecules without labeling. In previous study, we developed CARS spectroscopy in which Raman spectra were obtained with high frequency resolution by using a single broadband light source. In this spectroscopy, the probe beam was produced by an optical bandpass filter which has a limit of blocking range. This restricts bandwidth of light source and obtained Raman spectra. In this study, we use a combination of edge filters instead of a bandpass filter. By tilting the filters, we select bandwidth and intensity of the probe beam. Variable nature of spectral resolution and intensity are shown by using chloroform molecules as a test sample.