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All viewports are fragile and should be handled and mounted with extreme caution. Never scratch the viewing area-a weakened viewport may implode (or explode under wrong conditions). Make sure the "glass" chosen has a reasonable transmission at the wavelengths of interest.
Braze material may be noticeable on the glass around the sealing area of quartz viewports. This is not a manufacturing defect, products are verified such that braze material creep does not occlude the specified view area and the product passes leak check requirements. This material is not removed so as not to risk damaging the viewport lens.
For safety, we strongly recommend that no viewport is exposed to a temperature ramp of greater than 2-3°C per minute, and that no viewport be exposed to direct thermal radiation. To limit thermal gradients when heating viewports, we recommend the viewing area and the flange be covered with many layers of aluminum foil to act as a reflective shield.
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Product VacuCAD Files


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Flange / Mounting: DN63CF (4.50 in / 114.30 mm OD)
Window Material: Corning HPFS 7980 Fused Silica Excimer Grade 193
View Area: 1.40
View Area (Metric): 35.6
Window Thickness: 0.125
Window Thickness (Metric): 3.2
Flange Material: 304L SS
Sleeve Material: 304L SS
Thermal Range: -100C to 200C
Flatness : λ/4 @ 632nm Transmitted Wavefront
Parallelism : <10 Arc Seconds
Surface Finish: 20/10 Scratch-Dig
Transmission : >99.5%@193nm (Internal)
Homogeneity Grade: A
Inclusion Class: 0

Dimensional Drawings


Contact Us - VPRE-450EU -