Laser damage threshold is a topic of growing
importance in the High Energy Laser (HEL) industry
for defense and material processing. As lasers
become more powerful, optics, specifically thin film
coated optics, are subjected to higher levels of
power and have an increased risk of damage due to
the effects of absorption. In addition, losses due to
scattering also effect the ability of coated optics to
perform in HEL environments. Measuring absorption
and loss in thin film coated optics is of increasing
importance. One tool which is used to measure
these effects is a Cavity Ring Down Lossmeter
(CRDL). This project set out to build a CRDL
instrument that could measure optics at multiple
wavelengths with a precision of approximately 20
parts per million.
