Ultrasonic Machining Optical Glass – Optical Glass (CTE 7.1 x 10^-6 /K, 350 nm – 2.0 um); Ultrasonic Machining to +/-0.02 mm form. No minimum order; DFM review included with every RFQ.
We ultrasonically machine Optical Glass daily, in thicknesses from 0.5 – 25 mm. The controlling numbers: +/-0.02 mm form working tolerance, 0.3 mm blind features minimum features, and matte machined surface off the machine. Where the drawing asks for more, downstream lapping and polishing take over.
Specifications at a glance
| 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 | Ultrasonic Machining |
| Working tolerance | +/-0.02 mm form |
| Minimum feature | 0.3 mm blind features |
| Surface finish | matte machined surface |
| Thickness window | 0.5 – 25 mm |
| Edge condition | crack-free feature edges |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Process window
Ultrasonic Machining earns its place through blind cavities, non-round holes and stepped profiles that rotary tools cannot reach. Its boundary condition – material removal is slow, so it is reserved for features other processes cannot form – is the first thing our DFM review checks.
Beyond this page, Optical Glass routinely runs through dicing, laser cutting, cnc machining, sandblasting in our shop – most real parts combine two or three of these steps.
Getting the drawing right
The shop-floor rules that matter here:
- Material note: index-certified blanks must be oriented and serialized through the shop to keep melt traceability.
- Process boundary: material removal is slow, so it is reserved for features other processes cannot form.
- 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.
Application context
ultrasonic machining optical glass shows up across scientific instruments (reference flats, cells, prism mounts, stage inserts); optical sensors (sensor windows, filter caps, lens covers); laser systems (windows, beam splitters, debris shields). 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.
Engineers scoping this work usually also review AR coated glass materials, CCD screening plates, special-shaped glass plates.
Buyer questions, answered
What equipment runs the ultrasonic machining work?
20 kHz ultrasonic spindles with shaped diamond form tools.
Is there a minimum order for ultrasonic machining 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.
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.