Edge Grinding Optical Glass: Optical Glass (CTE 7.1 x 10^-6 /K, 350 nm – 2.0 um); Edge Grinding to chamfer +/-0.05 mm. Single-piece prototypes to production volumes, quoted from your drawing.
Ask any process engineer what makes optical glass difficult and the answer is specific: index-certified blanks must be oriented and serialized through the shop to keep melt traceability. Our edge grinding line is tooled around exactly that – CNC edge grinders with profiled diamond wheels – holding chamfer +/-0.05 mm on parts from 0.1 – 25 mm thick.
Specification envelope
| Material | Optical Glass (N-BK7, H-K9L and filter glass sets) |
|---|---|
| Thermal expansion (CTE) | 7.1 x 10^-6 /K |
| Service temperature | 400 C (Tg 557 C) |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.51 g/cm3 |
| Knoop hardness | 610 kg/mm2 |
| Refractive index | 1.5168 @ 587 nm |
| Stock thickness | 0.30 – 50 mm |
| Maximum blank size | 300 mm diameter |
| Process | Edge Grinding |
| Working tolerance | chamfer +/-0.05 mm |
| Minimum feature | 0.1 mm chamfer leg |
| Surface finish | ground C or R profile, polish option |
| Thickness window | 0.1 – 25 mm |
| Edge condition | C-chamfer, R-round, pencil or OG profile |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Process window
Edge Grinding earns its place through edge strength – a finished chamfer roughly doubles the bend strength of a cut edge. Its boundary condition – profiles below 0.1 mm leg length are lapped by hand and priced per edge – is the first thing our DFM review checks.
Beyond this page, Optical Glass routinely runs through double-side polishing, ultrasonic machining, laser cutting, polishing in our shop – most real parts combine two or three of these steps.
Design guidance
Before sending the RFQ, check these against your drawing:
- Material note: index-certified blanks must be oriented and serialized through the shop to keep melt traceability.
- Process boundary: profiles below 0.1 mm leg length are lapped by hand and priced per edge.
- 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.
The full rules live in our tolerance design guide and holes and edges design guide.
Where these parts end up
edge grinding optical glass shows up across optical sensors (sensor windows, filter caps, lens covers); machine vision (camera windows, ring-light diffusers, calibration plates); ccd inspection equipment (CCD cover plates, reference grids, stage glass). Background reading on the underlying material science: RP Photonics: optical glass.
The fastest route to a quote is geometry: use the 3D configurator below, or the site-wide custom glass machining 3D builder for fully custom parts.
Related reading on this site: optical polishing capability, CCD screening plates, BF33 microfluidic chip.
Frequently asked questions
What tolerances are achievable on Optical Glass parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Index-certified blanks must be oriented and serialized through the shop to keep melt traceability.
What thickness range do you stock for Optical Glass?
Standard stock spans 0.30 – 50 mm, with blanks up to 300 mm diameter. Other formats are sourced per order.
How does Optical Glass behave under heat?
CTE is 7.1 x 10^-6 /K and continuous service reaches 400 C (Tg 557 C), which is what drives its use where certified refractive index and dispersion matters.
What accuracy does edge grinding hold?
Chamfer +/-0.05 mm with minimum features of 0.1 mm chamfer leg. Profiles below 0.1 mm leg length are lapped by hand and priced per edge.
Specifications on this page were last reviewed by our engineering team in July 2026.