Compare Model Drawings, CAD & Specs Diameter Thickness Availability Price
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25.4 mm 9.52 mm
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In Stock
50.8 mm 12.7 mm
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  • Material
    UV Grade Fused Silica
  • Wavelength Range
    195-2100 nm
  • Surface Flatness
    λ/10 @ 632.8 nm
  • Surface Quality
    10-5 scratch-dig
  • Thickness Tolerance
    ±0.5 mm
  • Chamfers
    10QB20: 0.25-0.76 mm face width
    20QB20: 0.38-1.14 mm face width
  • Chamfers Angle/Tolerance
    45° ±15°
  • Cleaning
  • Clear Aperture
    Central 80% of diameter
  • Diameter Tolerance
    +0/-0.25 mm
  • Antireflection Coating
  • Wedge
    30 ±5 arc min


UV Fused Silica for UV, Laserline & Broadband Applications

UV Grade Fused Silica is synthetic amorphous silicon dioxide of extremely high purity providing maximum transmission from 195 to 2100 nm. This non-crystalline, colorless silica glass combines a very low thermal expansion coefficient with good optical qualities, and excellent transmittance in the ultraviolet region. Transmission and homogeneity exceed those of crystalline quartz without the problems of orientation and temperature instability inherent in the crystalline form. It will not fluoresce under UV light and is resistant to radiation. For high-energy applications, the extreme purity of fused silica eliminates microscopic defect sites that could lead to laser damage.

Slight Wedge Suppresses Internal Fringes

Highly parallel flats are unsuited for use as reference elements in interferometers as reflections from both surfaces follow the same optical path toward the viewer or imaging system, resulting in undesired large period ghost fringes.

Fizeau Interferometer Applications

A Fizeau Interferometer may be used to test the flatness of an optical surface, by comparing its figure against the known figure of the interferometer flat.

Fabry Perot Interferometer Applications

Fabry Perot interferometers use two interferometer flats with flat surfaces facing each other to form an air spaced resonant cavity.