Surfacing
The back of a semi-finished blank is generated to the prescription, then fined and polished. Freeform generators cut complex designs directly.
Laramy-KEyeglasses and Optical · Labs and Edging
Optical Labs and Edging In-house finishing or an outsourced lab.
Every pair of glasses passes through surfacing and finishing. The practice decision is how much of that to bring in-house. In-office edging can speed up single vision jobs and give more control, while a full-service lab handles surfacing, coatings and complex work.
2Core steps: surfacing, then finishing
≈70 mmTypical uncut lens diameter before edging
3–7 minEdging time, simple to complex jobs
Z80.1ANSI recommendations for Rx lenses
How glasses are made
Surfacing, coating and finishing
A lab turns a lens blank into a finished pair in a predictable sequence. Knowing the steps shows exactly which ones an in-office lab can take over.
Coating
Hard coats, anti-reflective stacks and tints are applied after surfacing and before finishing.
Laramy-KFinishing
Also called edging or glazing: the round lens is marked, blocked, edged to the frame shape and mounted.
Laramy-KStock lenses
Finished uncut single vision lenses come ready to edge, which is why single vision is the usual starting point for in-office finishing.
Laramy-KWhat an in-office finishing lab needs
In-office finishing is mostly about the tracer, blocker and edger, plus trained hands.
- Tracer and blocker for frame shape and centration
- An edger matched to your frame mix
- A trained operator and a mounting bench
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Edgers
Wet edgers grind with diamond wheels and water; dry robotic edgers use CNC tooling for finer control of bevel shape and placement.
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Tracer-blockers
Units such as the Essilor Instruments TCB 800 and TCB 500 trace the frame and block the lens before edging.
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Edging systems
Essilor Instruments USA lists the ES 800_M and ES 700_M, Neksia and Delta edging systems; NIDEK also makes lens edgers.
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Operator skill
Automation handles routine jobs, but experienced operators prevent costly mistakes on complex prescriptions and mounts.
Making the decision
When in-house edging makes sense
Even with in-office finishing, surfacing, coatings and premium designs generally still come from an outside lab.
Start with single vision
Stock finished single vision lenses can be edged the same day, which is where in-office finishing pays off fastest.
Keep complex work outside
Progressives, high-index drill mounts and specialty coatings usually stay with a full-service lab.
Train before you buy
Laramy-K’s OpticianWorks offers a free course on in-office finishing that is worth completing before choosing equipment.
Options compared
In-office finishing vs outsourced lab
| Turnaround | In-office: same-day possible on stock single vision. Lab: depends on surfacing, coating and shipping |
|---|---|
| Job mix | In-office: mostly single vision and routine mounts. Lab: progressives, freeform, coatings, specialty work |
| Investment | In-office: tracer, blocker, edger, space and training. Lab: no equipment cost |
| Quality control | In-office: your staff verify against the order. Lab: lab QC plus your check at dispensing |
| Remakes | In-office: breakage and remakes are absorbed in-house. Lab: handled under your lab’s remake terms |
Edge types by frame
- Full-eyewire: V-shaped bevel.
- Semi-rimless: flat edge with a groove for the nylon cord.
- Rimless: perfectly flat, smooth edge, drilled for mounting.
Standards that apply
ANSI Z80.1-2020 sets recommendations for prescription ophthalmic lenses, and every finished eyeglass lens must still meet the FDA impact-resistance rule in 21 CFR 801.410. Confirm how your lab documents both.
Common questions about labs and edging
What is the difference between surfacing and finishing?
Surfacing creates the prescription on the back of the lens. Finishing cuts that lens to the frame shape and mounts it.
Can we edge progressives in the office?
It is possible with the right equipment and training, but many practices keep progressives with a full-service lab for accuracy and coating options.
Wet or dry edger?
Wet edgers grind with water and diamond wheels; dry robotic edgers use CNC tooling and offer more control over bevel design.
Who is responsible for impact testing?
Under 21 CFR 801.410 the lens manufacturer tests, and importers count as manufacturers. Plastic prescription lenses may be tested on a statistical basis.
Where can staff learn finishing?
Laramy-K offers a free in-office finishing course through OpticianWorks.
References
- Laramy-K Optical. All about lens surfacing. Laramy-K
- Laramy-K Optical. What is lens edging and finishing? Laramy-K
- Essilor Instruments USA. Lens finishing systems and tracer-blockers. Essilor Instruments
- NIDEK. Lens edging products. NIDEK
- ANSI. Z80.1-2020 Prescription ophthalmic lenses: recommendations. ANSI
- US FDA. 21 CFR 801.410 impact-resistant lenses. eCFR
Bring in what you can do well
Start with single vision finishing, keep complex work at the lab, and train before you buy.
Equipment names are trademarks of their respective owners and are listed for reference only. Confirm specifications, service and training with each manufacturer. Process descriptions summarize published lab education materials.