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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.
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" OD)
Flange Material: 304L SS
Sleeve Material: 304L SS
Window Material: Corning HPFS 7980 Fused Silica Excimer Grade 193
Window Thickness: 0.125
Window Thickness (Metric): 3.2
View Area: 1.40
View Area (Metric): 35.6
Parallelism : <10 Arc Seconds
Flatness : λ/4 @ 632nm Transmitted Wavefront
Surface Finish: 20/10 Scratch-Dig
Thermal Range: -100C to 200C
Transmission : >99.5%@193nm (Internal)
Homogeneity Grade: A
Inclusion Class: 0
Dim A: 3.50
Dim A (Metric): 88.9
Dim B: 2.00
Dim B (Metric): 50.8
Dim C: 1.90
Dim C (Metric): 48.3

Dimensional Drawings


Contact Us - VPRE-450EU -