The wavelength on a UV LED flood lamp is the one specification that cannot be corrected after installation, which makes it the decision most worth slowing down for. Get it right on paper first, and every later choice gets easier.
Q: Which wavelength should a UV LED flood lamp use?
A: The wavelength that falls inside the photoinitiator absorption range stated on the adhesive or coating’s technical data sheet. Incure’s L-Series™ and W-Series™ flood lamps are each offered in 365, 385, 395, or 405 nm, and each unit ships factory-configured to one of them. If a line runs several materials, the chosen wavelength has to suit all of them, or the line needs more than one lamp.
Why the Choice Is Permanent
Unlike a mercury-arc flood lamp, whose bulb emits a broad spectrum, an LED flood lamp emits a single narrow band set by the diodes in its array. Incure configures that band at the factory. There is no field switch and no swappable filter, so a lamp ordered at 395 nm stays a 395 nm lamp. A wavelength mismatch discovered during qualification means replacing the unit, not adjusting it.
A Four-Step Wavelength Decision
- Read the data sheet for every material the lamp will cure, not just the first one. Note the stated cure wavelength or range and the required dose.
- Find the overlap. If every material lists a range that includes, for example, 385 nm, one lamp serves the whole line.
- Check intensity at that wavelength. Intensity is not uniform across the four options. On L88 through L1414, the 365 nm version runs measurably lower than the 385, 395, and 405 nm versions. On the W-Series™, the pattern reverses: W44 and W1212 read higher at 365 nm.
- Confirm with a cured sample at the chosen wavelength and production working distance before the order is final.
Email Us with the data sheets for every material on your line, and Incure’s engineers can identify which wavelength, if any, covers all of them.
Same Model, Different Wavelength, Different Exposure Time
Because intensity shifts with wavelength on several models, the same material can need a different exposure time on two lamps with identical curing areas. Consider a hypothetical material that cures at both 365 nm and 395 nm. If one wavelength version of a lamp delivers 20 percent less irradiance than the other, the exposure needed for the same dose rises by a factor of 1 ÷ 0.8, or 25 percent. The 20 percent figure here is illustrative; take the real intensity for each wavelength from the model’s specification sheet and recalculate the cure schedule rather than reusing one written for another wavelength.
Mixed-Material Lines
When no single wavelength suits every material, there are three workable paths:
- Standardize materials around one wavelength during process development, so one lamp serves the line.
- Dedicate lamps — one L-Series™ unit per wavelength, each at its own station. Every model accepts foot-switch, PLC, and RS232 inputs, so multiple lamps can share one control scheme.
- Use broadband exposure for the materials that need it. Incure’s F-Series™ arc flood lamps emit UVA and UVB, with visible output at 420 nm on F500 and F200P, at 420 and 460 nm on F400, and across the visible range on F900P.
The broadband route is covered in Incure’s UV flood lamp overview, which compares arc and LED output directly.
Questions to Answer Before Ordering
- Which wavelength range does each material’s data sheet specify?
- Does one wavelength fall inside every range?
- What is the model’s quoted intensity at that specific wavelength?
- Has a sample cured fully at that wavelength, at the production distance?
- Will future materials be developed around the same wavelength?
That last question is easy to skip. Standardizing new material development around the installed wavelength keeps a fixed-wavelength lamp useful as products change, instead of forcing a second purchase when a new adhesive arrives.
Wavelength and the Chamber
Changing wavelength does not change enclosure compatibility. L11 through L44 still pair with the C131C, C131D, and C141C chambers, and L88 through L1414 with the C191C, regardless of which of the four wavelengths the unit carries. Only the lamp itself needs to match the chemistry; the enclosure decision follows curing area.
Matching Flood and Spot Stations
Many lines pair a flood station with a spot-cure station for tacking or touch-up. Incure’s L9000™ spot lamp follows the same single-wavelength rule as the flood lines, so ordering both at the same wavelength lets one material qualification cover both stations. Ordering them at different wavelengths means the material has to be qualified twice, and the cure schedules cannot be shared between the two steps.
Where to Go Next
Incure’s UV LED flood lamp explainer covers how flood curing works and how curing area trades against intensity. Model-level wavelength and intensity details are in the L-Series™ product guide.
Contact Our Team to confirm the wavelength and model for every material on your line before ordering.
Visit www.incurelab.com for more information.