High Temperature Sapphire Zero Length
Sapphire viewports are offered on CF flanges. The viewports comprise a high-quality optic with precise flatness, parallelism, scratch and dig specifications. The single-crystal sapphire windows have excellent optical, physical, and chemical properties.
- Description
- Specifications
- Transmission Curve - Sapphire
- Additional Details
- Options
Description
The hardest of the oxide crystals, sapphire retains its high strength at high temperatures. Sapphire has a low coefficient of thermal expansion and low fluorescence, good resistance to thermal shock and scratching making this an excellent material for IR transmitting optics and robust applications. C-cut sapphire is selected for Torr Scientific sapphire viewports to minimize the effects of birefringence.
The ultra high vacuum (UHV) CF versions are offered using high-grade 316LN stainless steel flanges. Non-magnetic viewports are offered for low-energy applications or surface science applications needing low magnetic fields. The non-magnetic viewports use a non-magnetic weld ring instead of the regular kovar weld ring. TSL 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 300 °C with UHV performance, whilst the window offers broadband optical transmission through vacuum UV, visible to near infra-red. Various anti-reflective coatings to match customer reflectance requirements are processed at TSL and available as options listed in the AR coated viewport data sheets. Non-standard viewports can be manufactured on request, including re-entrant style microscope/camera viewports. Annealed copper gaskets and other component accessories are also supplied by TSL.
Seal Type | Braze |
---|---|
Maximum Temperature | 300 °C |
Minimum Temperature | minus 20 °C |
Maximum Rate of Temperature Change | 3 °C per minute |
Leak Rate | <1×10-10 atm-cc/sec (He) |
Pressure Range | 1 bar to 1×10-11 mbar |
Surface Quality | 60/40 scratch/dig |
Flatness | < 8λ |