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Quartz Glass

Optical Grade Fused Silica with UV Quality

Special Properties

  • Excellent ultraviolet transmission
  • High optical quality
  • High-purity glass composition
  • Extremely heat-resistant
  • Low coefficient of thermal expansion
  • Crystal-clear, water-white appearance
  • Operating temperature up to 1000 °C
  • Very high thermal shock resistance
  • Outstanding chemical strength
  • Low fluorescence
  • High electrical insulation properties
  • Chemically inert
  • Made by a flame hydrolysis process
  • Machinable by cutting, grinding, and polishing

Typical Applications

  • Windows for ultraviolet and deep ultraviolet light (DUV)
  • Glass wafers for semiconductor technology
  • Substrates used for mirror or filter coatings
  • UV-measuring instruments
  • Microscope slides and coverslips for medical applications
  • Industrial quartz products
  • High-temperature applications
  • Chemically resistant glass parts
  • Pressure windows
  • Quartz plates for laboratory equipment
  • Space technology


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Related glass types

If you need help choosing the right quartz material, visit our quartz glass FAQ website.


Optical Quartz Glass – Synthetic Fused Silica

Quartz glass used for optics is a synthetically produced, high-purity fused silica made by a particular flame hydrolysis process. The crystal-clear amorphous silicon dioxide material contains virtually no impurities and consists only of silicon and oxygen. This unique grade of quartz glass enables UV light transmission higher than 80% already at a wavelength of 185 nm. Quartz glass windowThe enormous operating temperature range and thermal load capacity of quartz glass are unparalleled. It can operate permanently up to 1000 °C and is highly resistant to thermal shock, resulting from its very low expansion coefficient. Moreover, the chemical properties of quartz glass are remarkable. The chemical resistance to bases exceeds that of almost all other glass materials. Quartz glass is durable and exceptionally resistant to saline solutions, acids, and water. Furthermore, its exceptional electrical performance makes quartz glass ideal for semiconductor technology. Since currents can only flow through mobile ionic impurities that are marginally present in quartz glass, it has low conductivity and excellent electrical insulation properties. These properties are essential for numerous electronic and semiconductor applications.


Quartz Glass Optics

We fabricate custom optics for the UV, visible, and infrared wavelength ranges, mainly from large quartz blocks, the so-called boules. We can select the raw glass for inclusion and bubble classes if necessary. Moreover, an index homogeneity level down to ≤ 0,5 ppm is available if this parameter represents a critical requirement.
Cutting the required material from the boule is the first step to producing a quartz glass optic. After this process, the quartz glass is shaped and finely ground, and the surface is polished according to the requirements. In this way, our company fabricates UV-transparent substrate glasses, glass wafers, microscope slides, and many other quartz glass items daily.


How can I obtain a price quote?

To request a quotation for windows, substrates, glass plates, or other parts of optical quartz glass with individual dimensions, please select a thickness from the table or use the following button.


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48h-Express icon 48-hour express manufacturing*


Specifications and Properties

Transmittance spectrum of synthetic
fused silica in the ultraviolet-to-infrared range

Spectral curve of UV-quartz glass
Enlarge the curve to show details

Glass thicknesses

As high-purity quartz glass is a block glass, there are usually no off-the-shelf standard thicknesses. Consequently, the glass thickness must be individually determined and manufactured. However, we continuously grind and polish the following glass thicknesses and tolerances to provide our customers with the best availability. You can even order these thicknesses with individual dimensions and take advantage of our 48-hour express production:
Click on a thickness to start an inquiry:

Glass Thickness (mm)


48h-Express manufacturing
0,175 ±0,020
0,30 ±0,025
0,30 ±0,050
0,50 ±0,025
0,50 ±0,030
0,50 ±0,050
1,00 ±0,025
1,00 ±0,100
1,10 ±0,100
2,00 ±0,150
3,00 ±0,025
3,00 ±0,100
Other thicknesses are possible on demand.


Light Transmission

  • T > 80% at 185 nm
    (UV-grade material = fused silica)

Refractive Index

  • nd = 1,4585


  • 2,20 g/cm3

Young's Modulus

  • 74 GPa (typical value)


  • Homogeneity classes per inquiry
  • Index homogeneity of the UV-class materials down to ≤ 0,5 ppm is possible on demand

Inclusion Classes

Glass Composition

  • Silicon dioxide (SiO2)

Operating Temperature

  • up to 1000 °C

Average Coefficient of Thermal Expansion

  • ≈ 0,57 × 10-6/K


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

Dielectric Constant

  • εr: 3,9 (500 MHz)


Fused Quartz Glass for Sight-Glass Applications

Besides the quartz glass type described before, we also process less sophisticated quartz materials. These lower material grades are typically used for high-temperature applications only requiring sight-glass quality. Since the inner material purity and the deep-UV transparency are of secondary concern in those cases, the less expensive Fused Quartz is the best choice for fabricating such items.

Unlike fused silica, this material is produced by melting natural quartz crystals. Hence, fused quartz is less pure than fused silica and contains far more contaminants and can't offer fused silica's purity level, homogeneity, or optical performance. Therefore, this glass type is only suitable for less demanding applications. Nevertheless, fused quartz has an almost identical coefficient of expansion, a similar heat resistance, and nearly the same good thermal properties as high-end quartz glass. Besides, it features almost the same chemical strength as fused silica and still offers better UV light transparency than most other glass types. Furthermore, the infrared transmission is similar and has the same crystal-clear appearance as optical quartz glass. Fused quartz is significantly more economical than the sophisticated fused silica materials described on this website. This material is the best choice for fabricating sight glasses for high temperatures, lamp housings, UV-lighting systems and lamps, transparent furnace panes, pressure-resistant windows, and other industrial quartz glass parts. You can find further details, specifications, and properties of this glass type in our Fused Quartz spec sheet. Please also refer to our Quartz Glass FAQ page for help selecting the right glass for your application.

Our company processes raw quartz glass materials from leading manufacturers in the quartz glass industry (Corning, Heraeus, Tosoh, SCHOTT, Saint-Gobain Quartz, Shin-Etsu, GE Quartz, and many others). We are pleased to share detailed properties, datasheets, and information about the glass qualities we supply on request.


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

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Last update: 28.02.2024