Made of natural fused quartz glass material, we produce sight glasses for high thermal load, front cover glasses for UV-lamps and similar less optically demanding components. Since for such applications optical quality and purity are of secondary concern and a high transmissivity below 200 nm usually is not required, natural fused quartz glass is an excellent material for the fabrication of such and similar parts at relatively low cost.
Natural fused quartz glass materials are produced by the melting of natural quartz (silicon dioxide) crystals and therefore cannot meet such a high optical performance and purity as our synthetic optical grade fused silica glass, but they are much more economical, especially at larger dimensions. The low coefficient of expansion and the high thermal strength are comparable to those of optical quartz glass material. Also the chemical resistivity is very good and on the same level as for fused silica. Besides that, the available high ultraviolet transmission down to about 200 nm is a key property for various applications.
Our fused quartz glass materials are made transparent by a more economical mechanical polishing process. The polishing finish does not offer optical-grade quality regarding flatness and surface quality. But the polished glass is clear and has almost no distortions or inhomogeneities when directly looked through with the naked eye. The possible thickness tolerances and the parallelism of this polished material is relatively coarse. But this is usually not an important factor in most areas of application for which these sight glass grade materials are used for.
To request a quote for windows of natural fused quartz glass with sight glass quality, please click on the following button:
For some thicknesses of our fused quartz glasses, we offer our 48 h Express Service for the fabrication and shipping within two working days. Below please find the available thicknesses within the express service. Please select the express service option in the inquiry form.
Dimensions within express-service are limited to 500 mm x 500 mm.
Show optical transmissivity of Fused Quartz Glass
(Sight glass quality)
All given details and specifications are mean reference values and are not guaranteed. In addition, please consider the "Notes on technical specifications"