IR Window Flange
Fourier-transform infrared surface science experiments require the use of high intensity, closely controlled infrared (IR) light. Since most IR light sources are not UHV compatible, a sealed viewport must be used to admit the light. Conventional viewport materials, such as pyrex and quartz can be readily sealed by vacuum brazing but do not usually admit the light frequencies required. Materials that DO transmit IR well are often costly, very soft and will become cloudy from moisture in the laboratory atmosphere.
The MTS' Differentially Pumped Window Flange (DPW) is used to mount special metal-halide windows to the ultra-high vacuum system that can not be sealed by conventional means. The flanges are available in a wide range of sizes (2¾" conflat size shown) to accept commercially available windows. The user can easily remove, polish and replace windows that have become cloudy, thereby extending useful life. Also, if the experimental requirements change, only the window itself need be changed, at considerable cost savings.
Under normal conditions your DPW will provide years of trouble-free service,
especially if simple maintenance is performed. By pumping on the differential
section with only a mechanical pump, UHV pressures on the inside can be routinely
achieved. Note that the "O" ring seals on both sides of the window (in the
cover plate as well as in the flange) should protrude a little to prevent
the metal surfaces from actually contacting the fragile window material. Should
you discover a situation to the contrary, stop and double check. It may be
time to replace the seals.
The DPW275 is designed to accept the user's standard, 38 mm OD X 6 mm thick window. No window is supplied. Because of the wide variety of window materials available, the choice is best left up to the user.
When replacing the cover, it is best to tighten the screws evenly. This
prevents binding and possible damage to the window. It also results in
a more uniform seal. Two sets (one spare) of seals are provided. The fluorocarbon
seal material can be baked to 150oC.
Store the spare seal set in a clean place to prevent damage or contamination.
Optional retainer with extended tube for N2 purge
DPW275 Flange assembly: $325.00
each
Optional extended retainer, add $25 each
Optional extended retainer, sold separately, $65 each P/N 10000885
Spare seal sets: $15.00 P/N 10001031
Other sizes and models are available. Please contact the factory at: