HIGH-RESOLUTION PULSED DYE-LASER CALIBRATION IN THE 500-350 NM REGION USING IODINE ATLAS REFERENCE LINES

A simple, inexpensive method for precisely calibrating high resolution, pulsed dye lasers in the 500-340-nm wavelength region has been devised. The residual portion of the laser beam exiting from an experiment is Raman shifted to longer wavelnegths in a high-pressure hydrogen cell. The Stokes shifted output is used to excite laser induced fluorescence (LIF) signals in I 2 vapor, which, in turn, are used to accurately calibrate the wavelength of the Raman shifted beam. The constant Raman shift, which can be precisely calculated, is then added to give the original laser wavelength. The method is readily adapted to computerized data acquisition and gives results of comparable accuracy to those of I2 LIF calibrations in the conventional 850-500 nm region.