AN AUTOMATED 2-CHANNEL WAVE-NUMBER CALIBRATION PROGRAM FOR A DIODE-LASER SYSTEM

An accurate and convenient two-channel wavenumber calibration program has been developed for a Laser Photonics diode laser system. The metho d is based solely on comparison of sample and reference spectra, as re corded and stored by the standard sweep control and data acquisition f acilities supplied with the system. The calibration program reads the sample and reference data files in Laser Photonics format, extracts th e spectral data, and converts them into standard IEEE data format. A s imple procedure is implemented for peak finding, with the sample peak wavenumbers calculated from a calibration curve determined by least-sq uares fitting to the reference wavenumbers. Provided the reference spe ctrum has a suitable distribution of peaks, a calibration precision of +/-0.0002 cm-1 or better is obtained for nitrogen-cooled diodes over the full width of the diode laser scan, and from +/-0.0005 to +/-0.001 cm-1 for closed-cycle helium cooling, of the same order as the origin al standard reference data. Given the rapid ongoing improvement in ava ilability of good reference spectra for all regions, this program offe rs a simple, reliable, and automatic procedure for accurate measuremen t of diode laser data. (C) 1994 Academic Press, Inc.