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 of 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
Related glass types
- BOROFLOAT®
(Borosilicate glass from SCHOTT) - Natural quartz glass
(Fused quartz for sight glass applications)
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 melting 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.
The 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 coefficient of thermal expansion.
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, acid, and water.
Quartz glass is ideal for semiconductor technology, not least because of its excellent electrical characteristics. Since currents can only flow through mobile ionic impurities that are marginally present in quartz glass, it has low conductivity and provides outstanding electrical insulation properties, which are essential for numerous electronics 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 raw 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 specific requirements. In this way, our company produces 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 quote for windows, substrates, glass plates, or other parts of optical quartz glass with individual dimensions, please select a material from the table or use the following button.
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48-hour express manufacturing
Specifications and Properties
Transmittance spectrum of synthetic
fused silica in the ultraviolet-to-infrared range
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, it must be individually specified and manufactured. However, we continuously grind and polish to various glass thicknesses and tolerances to provide our customers with the best availability. You can even order these with individual dimensions and take advantage of our 48-hour express production:
Click on a thickness to start an inquiry:
Glass THK |
Tolerance |
|
|---|---|---|
| 0,175 | ±0,020 | ✔ |
| 0,30 | ±0,050 | ✔ |
| 0,30 | ±0,025 | ✔ |
| 0,50 | ±0,050 | ✔ |
| 0,50 | ±0,030 | ✔ |
| 0,50 | ±0,025 | ✔ |
| 1,00 | ±0,100 | ✔ |
| 1,00 | ±0,025 | ✔ |
| 1,10 | ±0,100 | ✔ |
| 2,00 | ±0,150 | ✔ |
| 3,00 | ±0,200 | ✔ |
| 3,00 | ±0,025 | ✔ |
| Other thicknesses are possible on demand. | ||
Light Transmission
- T > 80% at 185 nm
(UV-capable material = fused silica)Refractive Index
- nd = 1,4585
Density
- 2,20 g/cm3
Young's Modulus
- 74 GPa (typical value)
Homogeneity
- Homogeneity classes per inquiry
- Index homogeneity of the UV-class materials down to ≤ 0,5 ppm is possible on demand
Inclusion Classes
- Inclusion-class options on request
Glass Composition
- Silicon dioxide (SiO2)
Operating Temperature
- up to 1000 °C
Average Coefficient of Thermal Expansion
- ≈ 0,57 × 10-6/K
Viscosity
- 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
In addition to the quartz glass type described before, we also process a less sophisticated quartz material called Fused Quartz. Although this material is also called quartz glass, it is quite different from the optical-grade materials described before. Unlike fused silica, this material is produced by melting natural quartz crystals. Hence, fused quartz is less pure than fused silica, contains far more contaminants, and can't offer fused silica's purity level, homogeneity, or optical performance. 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, this more economical quartz glass material is the best choice for fabricating such items, providing the cost control required.
Although fused quartz glass is only suitable for less demanding applications, fused quartz has an almost identical coefficient of expansion, a similar heat resistance, and nearly the same good thermal properties as high-end fused silica. Besides, it features almost the same chemical strength and still offers better UV light transparency than most other glass types. Furthermore, the infrared transmission is very high, and it has the same crystal-clear appearance as optical quartz glass.
Fused quartz is significantly cheaper than the sophisticated fused silica materials described before. Hence, this material is ideal 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.
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: April 24, 2024