Simultaneous Wavelength Comparison of Lodine-Stabilized Lasers at 515 nm, 633 nm, and 640 nm

The wavelengths of an Ar+ laser at 515 nm and of He-Ne lasers at 633 and 640 nm, all stabilized by saturated absorption in iodine-127, have been compared simultaneously by means of a servo-controlled Michelson interferometer. A new technique has been developed using a single polarization fiber for coupling the light to the interferometer and for examining the adjustment condition. This technique facilitates a comparatively simple and almost perfect optical adjustment. Relative uncertainties of less than 4 X 10-11 have been obtained for the comparison measurements.