How do you calculate optics polishing time?

Divide surfaces by the polishing rate for base time, then add the setup and inspection allowance. For 100 surfaces at 5/hr with a 20% allowance: 100 / 5 = 20 hr, x 1.20 = 24 hr.

Why include a setup and inspection allowance?

Polishing requires fixturing, blocking, and interferometer checks between cycles. The 20% allowance adds 4 hours to the 20-hour base, reflecting time not spent actively polishing.

What is a typical optics polishing rate?

It varies widely with material, aperture, and tolerance, from a fraction of a surface per hour for tight figure specs to several per hour for loose commercial optics. The example uses 5 surfaces per hour.

What allowance should I use for inspection?

For routine commercial optics 15-25% is common; precision optics requiring multiple correction-and-test loops can justify 40% or more. Set it from your own bench history.

Does this account for rework cycles?

No. The allowance covers normal setup and inspection, not surfaces that fail figure and need extra polishing passes. Budget those separately or raise the allowance.

How do I shorten total polishing time?

Raise the effective rate with better tooling or batching, and trim the allowance by streamlining fixturing and in-process metrology. Dropping the allowance from 20% to 10% here would save 2 hours.

Lasers, Optics & Photonics Manufacturing calculator

Optics Polishing Time Calculator

Optics polishing time estimates the labor and machine hours needed to polish a batch of optical surfaces to spec, including the realistic overhead for setup, fixturing, and interferometric inspection between runs. Optics shop planners and precision-manufacturing schedulers use it to load polishing cells and quote lead times for lenses, mirrors, and prisms. Because polishing is often the throughput bottleneck in precision optics and each surface may need repeated check-and-correct cycles, an estimate that ignores setup and inspection will badly understate the real clock. Adding a percentage allowance keeps the plan grounded in what actually happens on the bench.

What this calculator does

Estimate total polishing time for a batch of optical elements (lenses, flats, prisms) based on the number of surfaces, polishing rate, and setup allowance for fixturing and inspection.
Use this when scheduling polishing work for a production lot of lenses or flats, quoting delivery time to a customer, or deciding whether to add a second polishing spindle to meet demand.
It computes base polishing time from surface count and rate, then inflates it by a setup and inspection allowance to give total time.

Formula used

Base polishing time = number of optical surfaces / polishing rate
Total polishing time = base polishing time x (1 + setup and inspection allowance / 100)

Inputs explained

Number of optical surfaces to polish:
Polishing rate:
Setup and inspection allowance:

How to use the result

Use it when scheduling polishing capacity or quoting delivery for a batch of optical components.
It assumes a uniform polishing rate per surface and does not account for surfaces that need extra correction cycles to reach figure or finish.

Current U.S. benchmarks

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Industrial electricity averages 8.66 cents per kWh across the U.S. (EIA, Apr 2026), up 5.5% from a year earlier. Energy-intensive steps carry this directly into unit cost.
The U.S. has 11,261 computer and electronic products establishments employing about 815,443 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate optics polishing time? Divide surfaces by the polishing rate for base time, then add the setup and inspection allowance. For 100 surfaces at 5/hr with a 20% allowance: 100 / 5 = 20 hr, x 1.20 = 24 hr.
Why include a setup and inspection allowance? Polishing requires fixturing, blocking, and interferometer checks between cycles. The 20% allowance adds 4 hours to the 20-hour base, reflecting time not spent actively polishing.
What is a typical optics polishing rate? It varies widely with material, aperture, and tolerance, from a fraction of a surface per hour for tight figure specs to several per hour for loose commercial optics. The example uses 5 surfaces per hour.
What allowance should I use for inspection? For routine commercial optics 15-25% is common; precision optics requiring multiple correction-and-test loops can justify 40% or more. Set it from your own bench history.
Does this account for rework cycles? No. The allowance covers normal setup and inspection, not surfaces that fail figure and need extra polishing passes. Budget those separately or raise the allowance.

Last reviewed 2026-05-12.