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Beta Testing Site

This is a test instance of the site. Please go to https://www.accuglassproducts.com/ for the production site. 

Zero-Length Viewports

Zero-length viewport on CF flange Show CF Viewports for Zero-length viewport on CF flange
CF Viewports
Zero-length viewport on ISO flange Show ISO KF / LF Viewports for Zero-length viewport on ISO flange
ISO KF / LF Viewports

Zero-Length Borosilicate Glass Viewports

Accu-Glass’ Borosilicate glass viewports are ideal for general purpose use such as the direct observation of processes inside a vacuum chamber. The window material is a Corning 7056 type Borosilicate glass — one of the most common materials used in the construction of vacuum viewports. Our viewports are designed and built for both high and ultrahigh vacuum applications and employ the latest in glass-to-metal bonding technology to hermetically seal Borosilicate glass to nickel-iron alloy sleeves.

Borosilicate Glass Transmission

Optional AR Coatings

Features

  • Corning 7056 Borosilicate glass
  • Nickel-Iron alloy matched-expansion
  • High temperature rated to 350°C
  • UHV compatible materials
  • Stainless steel and NiFe construction
  • Conflat® and ISO NW compatible mounts

Specifications

Material 1 
Flanges, Stainless Steel304
Substrate, Glass 27056
Metal TransitionNi-Fe Alloy
Seal, Glass-to-MetalFused Glass
Vacuum Range 3 
UHV, Ultrahigh Vacuum1x10E-10 Torr
HV, High vacuum1x10E-8 Torr
Temperature Range 4 
Seal, Vacuum Brazed200°C
Flange, Conflat® Type CF450°C
Flange, ISO NW150°C
T° Gradient, Max/Minute10°C
Transmission Range 5 
375~1900nm>90%
  Scratch-Dig (both faces)60-40
  Flatness (per square Inch).0002 In
Notes 
  1. Since glass is susceptible to scratching and inherently weak under point stresses, caution must always be exercised when handling viewports. The proper handling of glass viewports and components will greatly minimize the chance of implosion hazard or injury.
  2. Corning® Borosilicate Glass
  3. Leak tested to 5x10-10 Standard cc/sec of He.
  4. Overall assembly ratings must be adjusted to that of its lowest rated component. For cryogenic service, the lowest recommended temperature is -80°C
  5. Transmission curves are provided for reference only. Transmission for individual viewports may vary based on glass substrate thicknesses, surface finish and/or other conditions.
  6. Unless specified otherwise, all dimensions are expressed in inches.

 

AR Coating Reflectance Curves