CHALCOGENIDE GLASSES FOR ACOUSTOOPTIC DEVICES .2. AS-GE-SE SYSTEMS

[As-Ge/Pb-Se/Te] glasses are investigated for their suitability for us e in acousto-optic devices. Thermal analysis, density, refractive inde x, acoustic velocity and acousto-optic figure of merit (M-2) are repor ted, incremental increase in refractive index per atomic percentage su bstitution of Te for Se, and Pb for Ge, has been calculated from the e xperimental data. The M-2 value of As-Se-Ge-Te-20-Pb-5 is reported as 965 +/- 81 at 10.6 mu m, relative to the M-2 value of SiO2 at 632.8 nm . The M-2 measurement was made using a novel method based on measureme nt of the total acoustic power inside the acoustic cavity.