AR Coating Optical Glass: Optical Glass (CTE 7.1 x 10^-6 /K, 350 nm – 2.0 um); R < 0.5% per face, 400 – 700 nm (custom bands 193 nm – 2 um). Single-piece prototypes to production volumes, quoted from your drawing.
Specify ar coating optical glass when the bare substrate falls short: anti-reflective multilayer, processed by ion-assisted e-beam deposition, brings Optical Glass to R < 0.5% per face, 400 – 700 nm (custom bands 193 nm – 2 um).
The numbers
| 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 |
| Treatment | AR Coating – anti-reflective multilayer |
| Specification | R < 0.5% per face, 400 – 700 nm (custom bands 193 nm – 2 um) |
| Deposition / method | ion-assisted e-beam deposition |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Specification advice
Three items decide most of the cost and lead time on this work:
- Material note: index-certified blanks must be oriented and serialized through the shop to keep melt traceability.
- Sequence matters: all machining happens before ar coating; post-coating rework is not economical.
- 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.
Process window
Beyond this page, Optical Glass routinely runs through drilling, polishing, etching, edge grinding in our shop – most real parts combine two or three of these steps.
Typical applications
ar coating optical glass shows up across ccd inspection equipment (CCD cover plates, reference grids, stage glass); scientific instruments (reference flats, cells, prism mounts, stage inserts); optical sensors (sensor windows, filter caps, lens covers). Background reading on the underlying material science: RP Photonics: optical glass.
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.
Related reading on this site: tolerance design guide, ultra-thin quartz discs, alkali-free display glass.
Common questions
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 does ar coating add?
Raises transmission from ~92% to above 99%. Applied by ion-assisted e-beam deposition to R < 0.5% per face, 400 – 700 nm (custom bands 193 nm – 2 um).
Is there a minimum order for ar coating optical glass?
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.
Specifications on this page were last reviewed by our engineering team in August 2026.