UV Curing calculator

UV Dose Mapping Calculator

Profiling a UV system typically yields 10–50 dose readings across the work surface. This calculator distills those down to the three numbers a process engineer cares about: the dose spread (max − min in mJ/cm²), the variation from the average (%), and a quick verdict on whether the worst spot is far enough from the cure floor. Use it to drive reflector tuning, lamp-spacing changes, or fixture redesigns.

What this calculator does

  • Take grid-pass radiometer readings and reduce them to the dose spread, max-to-min range, and a quick variation-from-average percent.
  • Use it after a profiling pass to quantify spatial dose variation across a fixture, belt width, or batch oven floor.
  • Reduces a UV dose-mapping pass to spread (mJ/cm²) and variation-from-average (%), the two metrics most cure specs use to gate a system.

Formula used

  • Dose spread = max − min (mJ/cm²)
  • Variation from average (%) = spread ÷ average × 100

Inputs explained

  • Minimum dose across grid: Lowest single reading from the profiling pass — typically a corner or shadowed spot.
  • Maximum dose across grid: Highest single reading from the profiling pass — usually under the lamp center.
  • Average dose across grid: Mean of all profiling positions; treat the median as a sanity check.

How to use the result

  • Use after every reflector / lamp / fixture change, before releasing a new product to production, and after troubleshooting a defect that points to localized undercure.
  • Three numbers cannot show pattern. A spread of 500 mJ/cm² could be one cold corner (fixable with a reflector) or a uniform tilt across the belt (fixable with lamp re-aim). Always plot the full grid for diagnosis; use this calculator for the headline metric on the report.

Common questions

  • How do I run a defensible dose-mapping pass? Use a profiling radiometer (logs irradiance vs position) or a grid of pucks left in place for one full pass. Cover the actual part footprint, not just lamp center. Document grid positions, lamp setpoint, line speed, and lamp hours so the result is comparable next time.
  • What spread is acceptable? Most production specs allow ≤15–20% variation from average. Cure-critical chemistries (medical adhesives, optical bonding) tighten to ≤10%. Above 25% you usually have a real cause that should be fixed before releasing the line to production.
  • Spread is high but the cold spot is still above the chemistry minimum — do I have to fix it? Strictly speaking no, you have process margin. Practically yes, because the cold spot will fail first as the lamp ages. Most plants tighten uniformity now to push the next intervention out further, especially on lamps near the end of useful life.
  • How does this differ from UV Dose Uniformity? Same math, different framing. UV Dose Uniformity is the audit / capability number ('our line runs at X% non-uniformity'). UV Dose Mapping is the diagnostic ('what does this reading set tell me about lamps and fixtures'). Use both — uniformity for trending, mapping for fixing.

Last reviewed 2026-05-12.