Quick answer: Fused Silica Round Glass Discs covers Fused Silica (CTE 0.55 x 10^-6 /K, 185 nm – 2.5 um); Diameter 2 – 450 mm, thickness 0.1 – 50 mm. Prototypes ship in 5-10 working days.
fused silica round glass discs are ordered for viewing ports, wafer carriers and sensor windows. The geometry envelope is Diameter 2 – 450 mm, thickness 0.1 – 50 mm, held to diameter +/-0.02 mm, in Fused Silica.
Specification envelope
| Material | Fused Silica (JGS1 (UV), JGS2 (standard), JGS3 (IR)) |
|---|---|
| Thermal expansion (CTE) | 0.55 x 10^-6 /K |
| Service temperature | 1,100 C continuous |
| Transmission range | 185 nm – 2.5 um |
| Density | 2.20 g/cm3 |
| Knoop hardness | 500 kg/mm2 |
| Refractive index | 1.458 @ 587 nm |
| Stock thickness | 0.10 – 50 mm |
| Maximum blank size | 450 x 450 mm |
| Geometry | Round Glass Discs |
| Size envelope | Diameter 2 – 450 mm, thickness 0.1 – 50 mm |
| Key tolerance | diameter +/-0.02 mm |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Manufacturing capability
One material, many routes: on Fused Silica we also quote double-side polishing, sandblasting, cnc machining, drilling, and multi-step drawings are the norm rather than the exception.
Production route: coring, cnc machining, edge grinding – selected per geometry and volume. Edge condition: entry/exit chamfer standard.
Specification advice
The shop-floor rules that matter here:
- Material note: its hardness and brittleness demand diamond tooling and controlled feeds.
- Hold the controlling dimension (diameter +/-0.02 mm) and let secondary dimensions carry standard tolerance – it is the single biggest cost lever.
- Over-specification is the quiet budget killer: a 20/10 scratch-dig face costs roughly three times an 80/50 face, so grade each surface individually.
For the complete framework, see the tolerance design guide and the holes and edges design guide.
Who orders this
The recurring buyers of fused silica round glass discs: laboratory instruments (cuvettes, sight glasses, stir-cell windows); ccd inspection equipment (CCD cover plates, reference grids, stage glass); scientific instruments (reference flats, cells, prism mounts, stage inserts). Background reading on the underlying material science: RP Photonics: fused silica.
The fastest route to a quote is geometry: use the 3D builder below, draw a dimensioned 2D drawing from it, or open the site-wide custom glass machining 3D + 2D builder for fully custom parts.
Engineers scoping this work usually also review wafer dicing process, CNC machining capability, precision glass grinding.
Frequently asked questions
Is there a minimum order for fused silica round glass discs?
No. Single prototypes are accepted, and pricing steps down at 10, 100 and 1,000 pieces.
How fast can prototypes ship?
Machined prototypes ship in 5 – 10 working days. Coated or bonded parts add 1 – 2 weeks depending on queue slots.
What files do you need for a quote?
A dimensioned PDF plus DXF or STEP geometry. If only a sketch exists, our drawing review service formalizes it before quoting.
Do parts ship with inspection data?
Dimensional reports, surface certificates and material certs per melt are available; specify the level on the RFQ.
Specifications on this page were last reviewed by our engineering team in September 2026.