High reflector absorptance measurements by the surface thermal lensing technique
- Lawrence Livermore National Lab., CA (United States)
- Eastern Michigan Univ., Ypsilanti, MI (United States). Dept. of Physics and Astronomy
Surface thermal lensing is an alternate configuration of a photothermal deflection system that was used to measure low levels of optical absorption. The thermal lensing configuration facilitated the alignment of the pump and probe laser beams by using a larger diameter probe beam. This technique was applied to high performance optical coatings, specifically high reflectors at 511 nm, zero degrees angle of incidence. The absorptance of these coatings was previously measured using a high power copper vapor laser system. A high power copper laser beam is focused onto a -2 mm diameter spot. A thermal camera senses the temperature rise with respect to the rest of the coating. The temperature change, power density and beam diameter were used with an empirical formula that yields optical absorption. The surface thermal lensing technique was able to resolve absorption levels lower than that achieved with the copper laser method.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 461394
- Report Number(s):
- UCRL-JC-125736; CONF-961070-5; ON: DE97051383
- Resource Relation:
- Conference: 28. annual symposium on optical materials for high power lasers - Boulder damage symposium, Boulder, CO (United States), 7-9 Oct 1996; Other Information: PBD: Nov 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Photothermal characterization of optical laser components at 10.6 {mu}m
Absorptance behavior of optical coatings for high-average-power laser applications