Why does the minimum matter more than the average?

Cure is local. Each part of the surface either received enough dose or did not, and a cold edge stays undercured however good the average looks.

What non-uniformity is acceptable?

Any figure is acceptable if the cold spot clears the requirement with margin, and none is if it does not. Uniformity is a diagnostic, not a specification.

How is this different from the dose mapping page?

This surveys the lamp, so the fixes are optical: reflector condition, alignment and end effects. The mapping page surveys a shaped part, where fixturing is the lever.

Should I raise the dose or restrict the width?

It depends where the cold spot is. At the extreme edges, restricting the fixture costs only usable width; through the middle, the whole profile must rise.

UV Curing calculator

UV Dose Uniformity Calculator: Does the Cold Spot Cure?

Measure how evenly a lamp delivers dose, then check the coldest point. Enter the minimum, maximum and average survey readings and the material's required dose.

What this calculator does

Measure dose uniformity across a lamp's cure surface and whether the cold spot still meets the requirement.

Formula used

Dose spread = maximum reading − minimum reading
Dose non-uniformity (%) = spread ÷ average × 100
Cold spot margin (%) = (minimum − required) ÷ required × 100
Hot spot to cold spot ratio = maximum ÷ minimum
Dose that governs cure = the minimum reading

Inputs explained

Minimum Dose Reading: Lowest dose measured anywhere a part passes.
Maximum Dose Reading: Highest dose measured across the same surface.
Average Dose Reading: Mean of the survey readings.
Required Cure Dose: The material's requirement, in the survey band.

How to use the result

Best suited to commissioning a lamp across its working width, diagnosing why parts at one belt edge fail, checking uniformity after a reflector clean.
Three summary numbers cannot describe a profile, and shape decides the cold region. Says nothing about where the cold spot is, which decides how to fix it. A coarse survey grid understates the spread and overstates the cold spot.

Common questions

Why does the minimum matter more than the average? Cure is local. Each part of the surface either received enough dose or did not, and a cold edge stays undercured however good the average looks.
What non-uniformity is acceptable? Any figure is acceptable if the cold spot clears the requirement with margin, and none is if it does not. Uniformity is a diagnostic, not a specification.
How is this different from the dose mapping page? This surveys the lamp, so the fixes are optical: reflector condition, alignment and end effects. The mapping page surveys a shaped part, where fixturing is the lever.
Should I raise the dose or restrict the width? It depends where the cold spot is. At the extreme edges, restricting the fixture costs only usable width; through the middle, the whole profile must rise.

Last reviewed 2026-10-01.