C-cut sapphire is selected for VacTechniche sapphire viewports to minimise the effects of birefringence. The ultra high vacuum (UHV) CF versions are offered using high grade 304L or 316LN stainless steel anges. Non-magnetic viewports are offered for low energy applications or surface science applications needing low magnetic elds. The non-magnetic viewports use a non-magnetic weld ring instead of he regular kovar weld ring. Flanges in 316L stainless steel are used for the high vacuum KF and ISO viewports. VacTechniche viewports are manufactured in cleanroom conditions and helium leak tested, cleaned and packed to UHV standards.
The rugged construction of the sapphire viewports allows repeated bake-out to 200 °C with UHV performance, whilst the window offers broadband optical transmission through vacuum UV, visible to near infrared. Various anti-re ective coatings to match customer re ectance requirements are processed at VacTechniche nd available as options listed in the AR coated viewport data sheets. Non-standard viewports can be manu- actured on request, including re-entrant style microscope/camera viewports. Annealed copper gaskets and other component accessories are also supplied by VacTechniche.
Transmission Curve – Sapphire