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Quartz Glass

Synthetic Fused Silica with optical quality

Special Properties

  • Excellent transmittance of ultraviolet light
  • Extreme thermal resistance up to 1000 °C
  • High-temperature shock resistance
  • Low coefficient of thermal expansion
  • High-purity glass composition
  • Very high chemical strength
  • Low fluorescence
  • Excellent electrical insulation properties
  • Produced by melting the purest raw materials

Typical Applications

  • UV-transparent optics
  • Glass windows for ultraviolet applications
  • Flame observation windows
  • Substrates for dielectric coatings
  • DUV-lighting applications
  • Components for laser systems
  • Microscope slides and cover-slips for UV-applications
  • Mechanical quartz glass components
  • UV-measurement technology
  • Chemical resistant windows
  • Glass parts for space applications
  • Heat resistant optical windows
  • Semiconductor technology

Get a price quote for
Quartz Glass Optics

48h-Express Service Also available in 48 h Express-Service*

Optical Quartz Glass is Synthetic Fused Silica

Quartz glass qualities used for optics consist of high-purity synthetically produced molten quartz. This type of glass is also known as Fused-Silica. The amorphous silicon dioxide material contains practically only silicon and oxygen and is characterized by very high purity. Only such grades of quartz glass materials offer such a great UV-transmittance of more than 80% already at 185 nm. This high UV transparency can hardly be achieved with any other glass.

Also unprecedented is the enormous operating temperature range and the thermal strength of quartz glass. It can be operated permanently at temperatures of 1000 °C and is very resistant to temperature changes. These exceptional thermal properties result from the low coefficient of thermal expansion of quartz glass.

High purity fused silica glass window for a semiconductor applicationThe unique chemical properties of this material are remarkable too. Quartz glass is exceptionally resistant to salt solutions, acids, and water. The chemical resistance to bases surpasses almost all other glass types.

Additionally, quartz glass has particularly good electrical properties due to its high purity. Since electrical currents can only flow through moving ionic impurities, which are marginal in quartz glass, it has a very low conductivity and therefore offers a very high insulation resistance, which is an essential requirement for many semiconductor and electronic applications.


Quartz Glass Optics

We produce quartz glass optics mainly from quartz blocks, the so-called boules. If required, the raw glass can be selected and specified for extremely low inclusions and bubbles. The index homogeneity of this type of quartz glass can be selected down to ≤ 0,5 ppm. To produce an optic from a glass boule, we first saw the raw material from the block, bring it into the desired shape and then grind and polish it according to the required specification. In this way, our company produces windows, substrates, wafers, microscope slides, laser components, and other quartz glass optics on a daily basis.


Quartz Glass for Sight Glass Applications

In addition to the optics grades of quartz glass described above, we also process less sophisticated quartz glass qualities for applications that only require sight glass performance. Since the inner material quality and DUV transparency are of secondary importance for such applications, the more economical natural fused quartz glass can usually be chosen for the manufacturing of such components. Unlike Fused Silica, these glass qualities are made by melting natural quartz instead of high purity synthetic quartz. Therefore, these materials cannot offer such a high internal glass purity and homogeneity as Fused Silica. Those types of materials are therefore less suitable for demanding optical applications. However, as they offer a similarly high thermal strength and are significantly more economical than the high-end glasses described before, such material qualities are typically used for high-temperature sight glasses, lamp housings, UV lighting applications, furnace windows, and similar components. You can find further information and properties of these glass types in our data sheet for fused quartz.


Request a Quote for Your Quartz Glass Component

To receive an offer for windows, substrates, slides or other components based on our UV-grade quartz glass material with individual dimensions, please click on the following button:


Get a price quote for
Quartz Glass Optics



Production as part of our Express Service 48h-Express Service

We also offer production of our UV-grade quartz glass as part of our 48 h Express-Service. The possible thicknesses within the express service are listed below. All these materials have double side polished surfaces. You can open a price inquiry form by clicking on the desired glass thickness below. Please select the "Express" option in the request form if you would like to use this service for an additional charge.

*Express-Service glass 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 glass

Transmission curve for optical quartz glass
Zoom in to view more details

Ultraviolet Transmission

  • T > 80% at 185 nm
    (only UV-grade materials = fused silica)
  • Transmittance of non-UV-grade quartz glass material
    per inquiry

Refractive Index

  • nd = 1,4585 (fused silica)


  • 2,20 g/cm3

Young's Modulus

  • typical 74 GPa


  • Homogeneity grades per inquiry
  • Index homogeneities of UV-grade quartz glass materials down to ≤ 0,5 ppm are possible on demand

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 the raw materials of all leading companies in the quartz glass industry (Corning, Heraeus, Tosoh, SCHOTT, Saint Gobain, GE, and others). Please feel free to inquire about detailed specifications and properties of all Fused Silica and fused quartz glass qualities we process.


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


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