Use of I2filters for stabilizing Ar+laser frequency and for attenuating parasitic scattering at the unshifted frequency in a molecular scattering spectrum

The two-iodine-cell technique for obtaining spectra of molecular light scattering with strongly attenuated parasitic scattering is described. One cell is used to attenuate parasitic scattering light, the other to stabilize the laser frequency on the iodine absorption line.