Translator Disclaimer
20 April 1998 Absorptance measurements of transmissive optical components by the surface thermal lensing technique
Author Affiliations +
The surface thermal lensing technique (STL) successfully resolved and measured the absorptance of transmissive optical components: near-normal angle-of-incidence anti-reflectors and beam splitters. The STL system uses an Ar ion laser to pump the components at 514.5 nm. The absorptance-induced surface deformation diffracts the HeNe probe beam into a photo- detector. The signal intensity was calibrated with a sample of known absorptance. The optical components were designed to function in a copper vapor laser (CVL) transport system, and were previously tested for absorptance with a high power CVL system at 511 nm. To assure proper absorptance data from the STL system, the pump laser power densities were set at the operational level of the coatings, absorptance time trends were monitored, and absorptance area scans were made. Both types of transmissive optics are more stable than the CVL high reflectors that were measured in another study. Parameter studies based on Fresnel diffraction theory were also performed to optimize experimental condition. The STL system was assessed to have 10 ppb sensitivity for absorption measurement given 2 W of pump power.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Robert Chow, John R. Taylor, Zhouling Wu, Yue Han, and Tian Li Yang "Absorptance measurements of transmissive optical components by the surface thermal lensing technique", Proc. SPIE 3244, Laser-Induced Damage in Optical Materials: 1997, (20 April 1998);

Back to Top