Abstract

The diode laser has become well established as a source of tunable infrared radiation for spectroscopic applications. However, its usefulness in spectroscopy is still limited by a small continuous frequency tuning range of typically 0.3 cm⁻¹. Even these limited scans tend to be rather nonlinear in frequency. These tuning problems make many of the tasks involved in spectroscopy difficult, especially the recognition of patterns within collected spectra and, to a lesser extent, the exact frequency calibration of spectral features. A strong motivation is therefore provided to overcome these difficulties and acquire the ability to generate long-range linear spectral displays. This paper describes computerization of a diode laser source (Laser Analytics SP-5150) and our method for linearizing and joining intrinsically rather short scans into continuous multiwave number scans. These linearized scans can then be readily and accurately calibrated from reference spectra.

© 1986 Optical Society of America