Guided-wave propagation at 10.6 μm in silver bromide thin films

Abstract
A germanium prism coupler has been used to couple a CO2 laser beam into thin AgBr films deposited on NaCl substrates. Thermographic phosphor screens and an infrared scanner were used to detect guided‐wave propagation in the films. Measurement of the TE0 and TM0 coupling angles yielded the film index (2.14) and thicknesses. The latter were in excellent agreement with independent thickness measurements.