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Optical Quartz Glass

Synthetic UV-grade fused silica

Special Properties

  • High transmission for ultraviolet light
  • Enormous temperature resistance up to 1000 ° C
  • Outstanding shock resistance
  • Low coefficient of thermal expansion
  • High-purity glass composition
  • Very good chemical resistance
  • Low fluorescence

Typical Applications

  • UV-transmitting optics
  • Applications with very high opertaing temperature
  • UV-windows
  • Coating Substrates
  • Laser optics
  • Microscope slides and cover slips for UV-applications
  • Mechanical quartz glass components
  • UV-measurement technology
  • Windows for space technology
  • Semiconductor technology


Optical Quartz Glass (Fused Silica)

Optical quartz glass consists of high-purity, synthetically produced, molten quartz raw materials. This type of glass is also called synthetic fused silica. It contains practically only silicon and oxygen (silicon dioxide) and is characterized by a very high purity.

The glass has exceptional optical transmission and a very low absorption in the ultraviolet light spectrum. Already at 185 nm more than 80 % of the light is transmitted. Such high UV permeability is possible with almost no other glass material.

The enormous temperature resistance of quartz glass is remarkable. It permanently can withstand temperatures of 1000 °C. Moreover, the material has a high heat shock resistance. These very good properties result from the low thermal expansion coefficient of the material.

High purity fused silica windowAlso outstanding is the chemical resistance of this unique glass. Quartz glass is extremely resistant to salt solutions, acids and water. The chemical resistance to bases surpasses almost all other glass materials.

Due to the high material purity, quartz glass has remarkably good electrical insulation properties. Since electrical currents can flow essentially only through moving ionic impurities and these impurities are only very small in the case of quartz glass, it offers a particularly high insulation resistance.


Optics Made of Quartz Glass

We make quartz glass optics mostly from block glass, the so-called "Boules". This raw material can be selected and specified on request with regard to inclusions & bubbles as well as to an index homogeneity up to ≤ 0.5 ppm. The raw glass is first sawn, formed into the desired shape, ground and optically polished, until a quartz glass optic has finally emerged. We manufacture windows, substrates, wafers, slides, laser optics and other components of optical grade quartz glass.

We also produce heat-resistant windows and sight glasses made of quartz glass. For such applications, this very high material quality and the high UV-transparency required for optics is often not necessary, so that lower grade natural fused quartz glasses, which are generally less expensive, can be used. These lower grade fused quartz glass materials are made of molten natural quartz. They do not offer such a high inner quality as fused silica does. They are therefore less suitable for demanding applications.



Quotation for Your Quartz Glass Optics

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:

Price quote for quartz glass



For applications which do not require high UV-transmission and whenever the optical quality is less important or if the glass is to be used only because of its thermal properties, please use the following button:

Price quote for sight glass
grade quartz components




Express Service 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. You can open a price request form by clicking on the desired thickness below. Please, select the express delivery option in the inquiry form:

Optical quartz express service thicknesses:
0,30 mm ; 0,50 mm ; 1,00 mm; 2,00 mm and 3,00 mm.

Natural quartz express service thicknesses:
1,00 mm ; 2,00 mm and 3,00 mm.







Transmittance of UV-grade fused silica

Zoom in and view details
(synthetic fused silica curve)


Light Transmissivity

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

Refractive Index

  • nd = 1,4585 (fused silica)


  • 2,20 g/cm3


  • Homogeneity specifications per request
  • Index homogeneities of UV-quality materials down to ≤ 0,5 ppm 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


Our company processes quartz glass from all leading raw glass manufacturers (Corning, Heraeus, Tosoh, SCHOTT, Saint Gobain, GE etc.). Further, detailed specifications and characteristics of all processed synthetic fused silica and natural quartz glass qualities 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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