Fused Silica UHV Laser Viewports With ‘VAR’ Anti-Reflective Coatings

VacTechniche Vacuum Optics – Viewports

Fused Silica UHV Laser Viewports With ‘VAR’ Anti-Reflective Coatings

VacTechniche laser viewports are offered with a two-layer ‘VAR’ anti-reflective coating on both sides of the window optimised to a customer specified laser wavelength. The coating reduces reflection to below 0.5% per face or 1% total at the wavelength specified. Please advise the laser wavelength with your enquiry or order.

Wavelengths between 240 nm and 1550 nm can be accepted as standard, although coatings for other wavelengths can be quoted on request. Viewports with coatings or a wavelength range can also be offered. The viewports comprise a high purity laser quality fused ilica optic with precise flatness, parallelism, scratch and dig specifications. The ultra high vacuum UHV) CF versions are offered using high grade 304L or 316LN stainless steel flanges.

Category:

Description

Reflectance Curve
Please note that the optical reflectance curves are approximations and should be used for reference only.

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. VacTechniche viewports are manufactured in clean room conditions and helium leak tested, cleaned and packed to UHV standards.

The rugged construction of the fused silica viewports allows epeated bake-out with UHV performance, whilst the window offers broadband optical transmis- ion through deep UV, visible to near infrared. 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.

Specifications

Seal Type Braze
Maximum Temperature 200°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 20 /10 scratch/dig
Flatness < 8λ
Laser Damage Threshold 2 J/cm2 at 530nm (note, varies with wavelength, laser type and cleanliness of optic)
Coating 2-layer ‘VAR’ coating optimised to customer specified wavelength between 240nm and 1550nm
Reflectance < 0,5% per face 1% total at the specified wavelength

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
VPZ16QVAR NW16CF 34 15 1.5 12.7 304L Kovar
VPZ16QVAR-LN NW16CF 34 15 1.5 12.7 316LN Kovar
VPZ16QVAR-NM NW16CF 34 15 1.5 12.7 316LN Niobium Yes
VPZ38QVAR NW35CF 70 32 3 12.7 304L Kovar
VPZ38LAQVAR NW35CF 70 38* 3.5 12.7 304L Kovar
VPZ38QVAR-LN NW35CF 70 32 3 12.7 316LN Kovar
VPZ38LAQVAR-LN NW35CF 70 38* 3.5 12.7 316LN Kovar
VPZ38QVAR-NM NW35CF 70 32 3 12.7 316LN Niobium Yes
VPZ64QVAR NW63CF 114 63 4.5 17.4 304L Kovar
VPZ64QVAR-LN NW63CF 114 63 4.5 17.4 316LN Kovar
VPZ64QVAR-NM NW63CF 114 63 4.5 17.4 316LN Niobium Yes
VPZ100QVAR NW100CF 152 89 6 19.9 304L Kovar
VPZ100QVAR-LN NW100CF 152 89 6 19.9 316LN Kovar
VPZ100QVAR-NM NW100CF 152 89 6 19.9 316LN Niobium Yes
VPZ150QVAR NW150CF 203 136 9.5 22.3 304L Kovar
VPZ150QVAR-LN NW150CF 203 136 9.5 22.3 316LN Kovar
VPZ150QVAR-NM NW150CF 203 136 9.5 22.3 316LN Niobium Yes
VPZ150QVAR-NM NW150CF 203 136 9.5 22.3 316LN Niobium Yes