UHV Viewports – Ultra High Vacuum Viewports

UHV Viewports - Types

Calcium Fluoride (CaF2) UHV Viewports

Calcium Fluoride (CaF2) is used optically as windows, prisms and lenses transmitting from the vacuum ultraviolet (VUV) into the infrared.  It is a physically and chemically stable optical material with good water and chemical resistance. Two qualities are manufactured, one for Visible and Infrared applications and the other specifically for Ultraviolet applications.  For Ultraviolet applications, these are grown from chemically pure powder.

Crystal Quartz (SiO2) UHV Viewports

Crystal Quartz (SiO2) is typically used as an optical window in the 3-5 micron region but can also be used as an optical filter. Crystal Quartz (SiO2) has a low density and a high thermal conductivity, making it an ideal material to be used for laser mirrors.

Silicon is grown by two different forms. One, is Czochralski (CZ), which contains some oxygen typically leading to an absorption band. The other is Optical Quality Silicon. This form is typically doped, and because it has a high refractive index, it must be anti-reflective coated to achieve a high optical transmission.

Magnesium Fluoride (MgF2) UHV Viewports

Magnesium Fluoride (MgF2) is grown by vacuum Stockbarger technique in various diameters. Magnesium Fluoride is a strong material and polishes very well. Magnesium Fluoride is slightly birefringent and is normally supplied with the optical axis cut perpendicular to the window face. Magnesium Fluoride is a water soluble material. Magnesium Fluoride transmits well into the VUV region and is an excellent choice for Excimer laser applications. Magnesium Fluoride is one of two materials that will transmit in the VUV 121nm (Lyman Alpha) range.

Sapphire UHV Viewports

The properties of Sapphire makes this material ideal for use in harsh environments. It has a unique combination of excellent physical, chemical and optical properties that allow it to retain its composition at elevated temperatures. This material will resist attack from acids and alkali up to 1000°C as well as Hydrofluoric Acid below 300°C. This material is inherently birefringent and has a transmission range from UV to NIR.

Zinc Selenide (ZnSe) UHV Viewports

Zinc Selenide (ZnSe) is used for Infrared windows, lenses, mirrors and prisms between 0.5 microns and 22 microns. This material is widely used in the Forward Looking IR Systems (FLIR).

Fused Silica UHV Viewports

Fused Silica is glass consisting of silica in amorphous (non-crystalline) form. It differs from normal glasses in that it contains no other materials, which are added to glass to lower the melt temperature. This material is non-birefringent and has high working and melting temperatures. It is widely used in the semiconductor sector as well as laboratory equipment. It transmits UV better than other glasses. The low Coefficient of Thermal Expansion (CTE) of this material makes it a useful material for precision mirror substrates.

Over Pressure Sapphire UHV Viewports

Over-Pressure Sapphire Viewports are intended for a vacuum system where there is not a burst disc or other device in place to withstand a sudden pressure increase. It is the customer’s responsibility to ensure the vacuum system cannot be pressured beyond the 200 psi rating that Jacarem’s Over-Pressure Viewports are designed to withstand.

Re-Entrant UHV Viewports

These specific UHV viewports are perfect for allowing you to introduce cameras or other customer specific tools into the vacuum chamber.  Jacarem can customize our UHV Re-Entrant Viewports to be customer specific in regards to length, size, window material, mounting material and specified coatings wavelengths when needed.

RF UHV Viewports

RF Viewports transmit RF or microwave power from a vacuum into an air filled or inert gas filled transmission line. An example of this would be a waveguide. It is a resonant cavity designed to maximize RF (radio frequency) power transmission, with minimal loss over a desired frequency range.