Calcium Fluoride Zero Length Viewports VacTechniche Vacuum Optics
VacTechniche calcium fluoride viewports are offered in CF, ISO and KF flange styles. The clean, UHV CF versions are offered using 304L or 316LN stainless steel flanges. Non-magnetic viewports are offered as standard using annealed stainless steel weld rings and high grade 316LN and CF flanges. Flanges in 316L stainless steel are used for the high vacuum KF and ISO viewports.
Description
The rugged, bonded construction of the calcium fluoride viewports allows bake-out to a maximum of 120 °C with ultra high vacuum (UHV) performance whilst the window offers extended broadband optical transmission from deep UV to the infrared. Specially coated optics optimised to minimise reflecance at customer specified wavelength can be quoted on request.
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 VacTechniche.
Transmission Curve – Calcium Fluoride
Specifications
| Seal Type | Bond |
| Maximum Temperature | 120°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 1×10-9 mbar |
| Surface quality | 60 /40 scratch/dig |
| Flatness (prior to bonding) | λ/4 |
Cross Sections / Diagrams
PARTS & VARIATIONS
| Part Number | Flange Type | OD mm | View Diameter mm | Optic Thickness mm | Flange Thickness mm | Flange Material | Weld Ring Material | Non-Magnetic |
| BVPZ16CaF2 | NW16CF | 34 | 15 | 1.5 | 12.7 | 304L | 316L | |
| BVPZ16CaF2-NM | NW16CF | 34 | 15 | 1.5 | 12.7 | 316LN | 316L Annealed | Yes |
| BVPZ38CaF2 | NW35CF | 70 | 32 | 3 | 12.7 | 304L | 316L | |
| BVPZ38LACaF2 | NW35CF | 70 | 38 | 3.5 | 12.7 | 304L | 316L | |
| BVPZ38CaF2-NM | NW35CF | 70 | 32 | 3 | 12.7 | 316LN | 316L Annealed | Yes |
| BVPZ64CaF2 | NW63CF | 114 | 63 | 5 | 17.4 | 304L | 316L | |
| BVPZ64CaF2-NM | NW63CF | 114 | 63 | 5 | 17.4 | 316LN | 316L Annealed | Yes |