Chromium-Doped Luminescent Glasses for Raman Intensity Calibration with 785 nm Laser Excitation

Abstract

In work reported previously we, and the McCreery Group at Ohio State University, have proposed the use of glass luminescence standards for the calibration of the Raman spectral intensity. We now have a program underway that is directed at the development of such secondary standards for the calibration of the Raman instrument response function. The first Raman intensity standard to be certified and issued by NIST this year will be for the relative intensity calibration of Raman spectra excited at 785 nm. in general, for any laser excitation wavelength, the calibration procedure is based on the use of luminescent glasses, doped with either transition metal or rare earth ions, that will furnish structureless, broad-band emission spectra upon laser excitation, over any chosen Raman range. For any selected glass standard, the intensity of the luminescence spectrum is calibrated versus the radiant output of a NIST-calibrated white light source, thereby transferring the white light calibration onto the output emission of the luminescent glass.