Quartz Viewports

Accu-Glass' Fused silica viewports are rated for both high and ultrahigh (UHV) vacuum applications. Vacuum Viewports are offered in two (2) fused silica grades... our UV (ultraviolet) material is suitable for most optical applications and certified to meet or exceed 80% external transmittance at 185nm. The DUV (deep ultraviolet) grade is equivalent to Suprasil‑1® and with the exception of inclusion specification, is virtually identical to the UV material.

Fused silica (Quartz) viewports outperform glass viewports in their transparency to ultraviolet radiation and a high resistance to discoloration. Since poor surface finish can contribute as much as 10% to overall transmission losses, our UV and DUV viewports are supplied with flat faces that have been polished to a 40-20 and 20-10 scratch-DIG specification respectively. DUV viewports are recommended for service below 200nm.

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Fused Silica (Quartz) Viewports
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CF Fused Silica Viewports, 0.63 to 7.78 view diameters
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219
Ultrahigh Vacuum CF Compatible Flanges
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High Vacuum ISO NW Compatible Flanges
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Lead-Silver (PbAg) Braze Alloy (200­°C Maximum)
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ISO Fused Silica Viewports, 0.63 to 1.40 view diameters
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Fused Silica Viewports

AGPs’ Fused silica viewports are rated for both high and ultrahigh vacuum applications. Viewports are offered in two (2) fused silica grades... our UV (ultraviolet) material is suitable for most optical applications and certified to meet or exceed 80% external transmittance at 185nm. The DUV (deep ultraviolet) grade is equivalent to Suprasil‑1® and with the exception of inclusion specification, is virtually identical to the UV material. Fused silica viewports outperform glass viewports in their transparency to ultraviolet radiation and offer a high resistance to discoloration. Since poor surface finish can contribute as much as 10% to overall transmission losses, our UV and DUV viewports are supplied with flat faces that have been polished to a 40–20 and 20-10 scratch-DIG specification respectively. DUV viewports are recommended for service below 200nm.

Fused Silica Transmission Curves
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Features

  • Fused Silica (Synthetic Quartz)
  • Ultraviolet and deep ultraviolet grades
  • Optically polished substrate faces
  • UHV compatible construction
  • High Temperature rated to 200°C
  • Stainless steel construction
  • Conflat® and ISO NW compatible mounts

Specifications

Material 
Flanges, Stainless Steel304
Substrate, QuartzFused Silica
Metal Transition, Stainless304
Seal, Vacuum BrazedPbAg Alloy
Vacuum Range 1 
UHV, Ultrahigh Vacuum1x10E-10 Torr
HV, High vacuum1x10E-8 Torr
Temperature Range 2 
Seal, Vacuum Brazed200°C
Flange, Conflat® Type CF450°C
Flange, ISO NW150°C
T° Gradient, Max/Minute10°C
Transmission Range 3 
200~200nm, UV Grade≥80%
  Scratch-Dig, both faces40-20
  
185~2000nm, DUV Grade≥80%
  Scratch-Dig, both faces20-10
Notes 
  1. Leak tested to 5x10-10 Standard cc/sec of He.
  2. Overall assembly ratings must be adjusted to that of lowest rated component. Fused silica-to-metal seal is a low temperature lead-silver braze alloy that melts at 305°C. Temperature monitoring sensors should always be placed between heat source and braze joint... i.e. when heat source originates inboard of seal/braze joint (through the center of the window), sensor must be placed on window substrate, outboard of heat source, but inboard of seal/braze joint. Conversely, if heat source originates outboard of seal/braze joint, sensor must be placed on stainless steel sleeve outboard of seal/braze joint.
  3. Transmission curves are provided for reference only. Transmission for individual viewports may vary based on thicknesses, surface finish and/or other conditions.
  4. Unless specified otherwise, all dimensions are expressed in inches.
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