Scattering of Stimulated Emission in Laser Materials

Abstract

An important consideration in the determination of threshold for laser oscillation and of laser efficiency is the scattering and diffraction losses which are present in the resonant optical cavity. Previous techniques for measuring such losses include: (1) conventional techniques for small-angle scattering, and (2) variation of the cavity loss in a known manner [ R. J. Collins D. F. Nelson , in Proceedings of the Conference on Optical Instruments and Techniques, HabellK. J., ed. ( Wiley, New York, 1963)]. The first technique leaves uncertain the acceptance angle of the resonant cavity for scattered radiation. This paper describes the extension of the second method to permit measurement of losses effective in prohibiting laser oscillation in materials which are not operative as laser oscillators. Thus, the technique discussed is useful in evaluating otherwise promising laser materials. Scattering losses in some potential organic laser materials are obtained using the technique described.