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Optical Grade Quartz Glass

Synthetic fused silica with UV-Quality

Special Properties

  • High transmittance of ultraviolet light
  • Enormous thermal strength up to 1000 ° C
  • Outstanding temperature shock resistance
  • Low coefficient of thermal expansion
  • High-purity glass composition
  • Very resistant to chemicals
  • Low fluorescence

Typical Applications

  • UV-transmitting optics
  • Applications with very high operating temperatures
  • UV-windows
  • Substrates for dielectric coatings
  • Laser optics
  • Microscope slides and cover-slips for UV-applications
  • Mechanical quartz glass components
  • UV-measurement technology
  • Chemical resistant windows
  • Windows for space technology
  • Semiconductor technology applications


Optical Quartz Glass is Synthetic Fused Silica

Quartz glass qualities that can be used for optics consist of high-purity, synthetically produced, molten quartz raw materials. This type of quartz glass is also called synthetic fused silica. It contains practically only silicon and oxygen (silicon dioxide) and is characterized by a very high purity.

Optical quartz glass has an exceptional high transmissivity and a very low absorption for ultraviolet light. Already at 185 nm more than 80 % of the light can be transmitted. Such high UV-permeability is possible with almost no other glass material.

The enormous operating temperature range and the thermal strength of quartz glass is remarkable. It permanently can be used at temperatures of 1000 °C. Moreover, quartz glass material has a high thermal shock resistance. These very good properties result from the small thermal expansion coefficient of the material.

High purity fused silica window for a semiconductor applicationAlso outstanding are the chemical properties of this unique material. Quartz glass is extremely resistant to salt solutions, acids and water. The chemical resistance of quartz glass to bases surpasses almost all other glass materials.

Due to the high material purity, quartz glass has remarkably good electrical insulation properties. It offers a particularly high insulation resistivity, since electrical currents can flow essentially only through moving ionic impurities and these impurities are very small in the case of quartz glass. This is an important property not only for semiconductor applications.


Quartz Glass Optics

We make quartz glass optics mostly from block glass, the so-called "Boules". On request, this raw material can be selected and specified with regard to inclusion- and bubble class. The index homogeneity of this optical quartz glass can be chosen down to ≤ 0.5 ppm. The raw glass is then first sawn, formed into the desired shape, ground and optically polished until finally a quartz glass optic is created. Our company manufactures optical windows, substrates, wafers, microscope slides, laser optics and other quartz glass components every day.


Sight Glass Grade Quartz Glass Materials

We also produce temperature-resistant sight glasses made of quartz glass. For such applications, an optical grade material quality and the high UV-transparency are often not necessary, so that generally the less expensive lower grade natural fused quartz materials can be used. In contrary to optical-quality-fused silica, these materials are produced by melting natural quartz. However, they do not offer such a high inner quality as fused silica does. Those quartz materials are therefore less suitable for demanding optical applications and are used for sight glass applications usually.


Get a Quote for Your Quartz Glass Component

If you would like to request a quote for windows, substrates, slides or other quartz glass components with optical quality and individual dimensions, please click on the following button:


Request a price for
Quartz Glass Optics


Express Service Production 48h- Express Service icon

Also for some quartz glasses we offer our 48h-Express-Service. The glass thicknesses available in the scope of the express-service are listed below. All of these materials have double side polished surface finishes. You can open a price request form by clicking on a desired thickness below. Please, select the express option in the inquiry form:

Express-Service thicknesses:
0,30 mm ; 0,50 mm ; 1,00 mm; 2,00 mm and 3,00 mm.





Specifications & Properties


Transmittance of UV-grade fused silica

Zoom in to view more details
(Transmittance curve for synthetic optical quartz glass)


Optical Transmission

  • T > 80 % at 185 nm
    (only quartz glass with UV-quality = fused silica)
  • Transmittance of non-UV-grade quartz material
    on request

Refractive Index

  • nd = 1,4585 (fused silica)


  • 2,20 g/cm3


  • Homogeneity specifications per request
  • Index homogeneities of UV-grade quartz materials down to ≤ 0,5 ppm are possible on request

Inclusion Classes

Average Coefficient of Thermal Expansion

  • approximately 0,57 x 10-6/K


  • Softening point approximately 1585 °C
  • Annealing point approximately 1042 °C
  • Strain point approximately 893 °C

Dielectric Constant

  • εr: 3,9 (500 MHz)


Our company processes quartz glass from all leading raw glass manufacturers (Corning, Heraeus, Tosoh, SCHOTT, Saint Gobain, GE etc.). Further, detailed specifications, and properties of all optical fused silica and fused quartz glass qualities we process are available on request.



All given details and specifications are mean reference values and are not guaranteed. In addition, please consider the "Notes on technical specifications"


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