Absolutní frekvenční posuvy jodem stabilizovaných laserových etalonů zpusobené čistotou jodu absorpčních kyvet

Results of measurement of purity of a set of iodine cells for laser stabilization made at our institute are presented. The purity was tested by improved method based on measurement of induced fluorescence and evaluation by the Stern-Volmer formula. This method was improved by innovation of the fluorescence detection system by introducing compensation for the pumping laser spectral and power instabilities. Further the absolute frequencies of selected iodine hyperfine transitions were measured in direct laser frequency comparison performed with a set of iodine-stabilized Nd:YAG laser etalons with the reproducibility well below the kHz level. The results indicating the iodine cell purity are presented with relation to the absolute frequency shifts. This highlights the influence of iodine cell quality onto the stability and absolute frequency of lasers etalons and also shows the way towards improvements of the iodine cell manufacturing technology