Abstract
Some Parameters of a laser crystal are estimated simultaneously from a laser ray 2-wavelengths method using perpendicularly polarized probe lights at wavelength of ruby laser (694nm) and auxiliary He-Ne gas laser (633nm). This method is actually applied to some ruby laser rods, and the next parameters are determined. Those are absorption coefficient αo for ordinary ray at 694nm, that αe for extraordinary ray, Ioss coefficients γo, γe, and normalized populationin version η. They are useful in analyzing the behavior of ruby laser amplifier by rate equations.