SYMPOSIA PAPER Published: 01 January 1986
STP23129S

Effect of Overcoats on 355-nm Reflectors

Source

Previous experiments have demonstrated that halfwave overcoats of a low-index coating material are effective in increasing the damage thresholds of dielectric high reflector coatings (HR's) at the wavelengths of 1064 nm and 248 nm. This overcoat layer led to a 50% increase in damage threshold at 1064 nm and to a 100% increase in threshold at 248 nm. This paper presents new results on the effect of halfwave overcoats at an intermediate wavelength: 355 nm.

Results reported at last year's Boulder Damage Symposium indicated that halfwave silica overcoats were detrimental to the damage thresholds of HR's at 355 nm. New results confirm that silica overcoats decrease thresholds and also show that magnesium fluoride overcoats do not improve the thresholds at 355 nm. A series of eight reflectors without overcoats had an average threshold of 2.4 J/sq. cm. The addition of silica overcoats decreased the average threshold by 2%, while magnesium fluoride overcoats decreased the threshold by an average of 7%.

Author Information

Carniglia, CK
Hart, TT
Staggs, MC
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E13
Pages: 285–290
DOI: 10.1520/STP23129S
ISBN-EB: 978-0-8031-4997-7
ISBN-13: 978-0-8031-0960-5