Interference polarizers can be successfully used in lasers and laser devices as independent optical element substituted crystal polarizers. Today, the use of crystal polarizers in some cases can lead to definite difficulties in accordance with peculiarities of laser cavity construction. The novel laser technologies and design of laser elements defined the new demands to optical coatings. In modern lasers interference polarizer can be considered as one of the main element that operates laser radiation. According to special optical outline and the requirements to optical characteristics of laser polarizers can be bryuster or mirror-type. The stable of spectral characteristic at a definite angle is one of the most important parameter. It was shown how optical thickness of each layer influence on angle stability. On the other hand high stable was achieved by using electron-beam ion assisted deposition. The coatings were deposited on the surface of optical glass BK-7 or quartz. Generally, refractory oxides were used. The achievement of the condensation layers structure was provided by active O2 + ions. It was shown, that smooth cleaning by neutral ions as before the evaporation definite separate layer, as after stabilized the optical properties of polarizer. Moreover, the using of ion source allowed increase laser damage threshold. It can be underline that some advantages of ion source revealed during evaporation materials in visible and especially ultra violet region. Also, laser strength was rather more at 1535 nm for ion-assisted deposited films. The average parameters were: minimum transmission efficiency TP < 97%, extinction ratio TP/TS <500, laser damage more than 10 J/cm2, 10 nanosecond pulse at 1064 nm in laser spot 200 μm.

Date Published: 25 September 2014
PDF: 9 pages
Proc. SPIE 9192, Current Developments in Lens Design and Optical Engineering XV, 919213 (25 September 2014); doi: 10.1117/12.2058251

Published in SPIE Proceedings Vol. 9192:
Current Developments in Lens Design and Optical Engineering XV
R. Barry Johnson; Virendra N. Mahajan; Simon Thibault, Editor(s)