Laser Research Optics has introduced a line of sapphire cover glass windows that have lower bulk absorption and about 30 times higher thermal conductivity than quartz protection glasses.

Laser Research Sapphire Fiber Laser Windows feature Mohs 9 hardness which is second only to diamond and have A/R coatings on both sides to provide transmission of > 99.5 percent @ 1.06 microns with > 80 percent @ 650-670 nm. Reducing focus shift and the deterioration of beam quality, these sapphire windows can withstand steel splatter, flash and debris better than fused silica.

Ideally suited as debris shields on 1,064 nm cutting and welding lasers, Laser Research Sapphire Fiber Laser Windows reduce the number of required lens changes on high-power lasers from 4 kW and above and extend their service lifetime. Providing a 10-5 scratch-dig finish and 1/4 wave transmitted wavefront, they are available in 0.5" and 2.0" sizes.