Optical Polishing vs Mechanical Polishing: How to Choose – custom precision glass machined to drawing with inspection reports. No minimum order; DFM review included with every RFQ.
The optical polishing vs mechanical polishing: how to choose decision is really about sub-nanometer optical faces versus fast flat matte faces. The short version: pitch polish for optical faces; lapping when flatness matters but clarity does not.
Side by side
| Polishing | Lapping | |
|---|---|---|
| Tolerance | flatness to lambda/4 per 25 mm | flatness 1 – 3 um |
| Min feature | Ra below 1 nm | thickness +/-0.003 mm |
| Finish | scratch-dig 40/20 to 20/10 | Ra 0.2 – 0.6 um matte |
| Thickness window | 0.2 – 50 mm | 0.2 – 40 mm |
| Strength | optical-grade faces with certified scratch-dig and interferometer-verified flatness | restoring flatness and parallelism on plates and repairing bowed stock |
| Limit | steep aspect parts and deep pockets polish unevenly; those faces are specified as fine-ground | lapped faces are translucent-matte; optical clarity requires a subsequent polish |
The decision axis is sub-nanometer optical faces versus fast flat matte faces. Pitch polish for optical faces; lapping when flatness matters but clarity does not.
Design guidance
The shop-floor rules that matter here:
- 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.
Who orders this
The recurring buyers of optical polishing vs mechanical polishing: how to choose: ccd inspection equipment (CCD cover plates, reference grids, stage glass); led packaging (groove covers, phosphor carriers, package windows); oled packaging (cover lids, frit-seal frames, fill-port plates).
If the part is easier to draw than describe, the custom glass machining 3D + 2D builder turns dimensions into an RFQ in a few minutes.
For adjacent specifications, see high-purity quartz guide, optical glass options, glass wafer bonding.
Common questions
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.
Which should I choose?
As a rule: pitch polish for optical faces; lapping when flatness matters but clarity does not. Borderline cases are worth a materials review with our engineers.
Specifications on this page were last reviewed by our engineering team in August 2026.