Spot Curing vs Area Curing: What Is the Difference?
Spot curing focuses light into a millimeter-scale spot at very high peak irradiance for precision adhesive points; area curing uses an emitting window from tens of millimeters to over a meter.
One-sentence answer: Spot curing focuses light through a light guide or LED head into a millimeter-scale spot with very high peak irradiance (37 W/cm² mercury, 27.3 W/cm² LED) for precision adhesive points; area curing uses an emitting window from tens of millimeters to over a meter to cover coatings, inks or laminated surfaces at 2–25 W/cm², with modules that tile together. The criterion is "how large an area, and how many places".
Grouped by spectrum into single-wavelength and broad-spectrum, and by form factor into spot and area curing. Image source: Excelitas UV Curing Product Selector Guide.
Comparison
| Item | Spot curing | Area curing |
|---|---|---|
| Spot / window | 3–12 mm spot | 76 × 10 mm to 1,350 × 20 mm |
| Peak irradiance | Very high | Moderate |
| Multi-point | Multi-leg light guides, cure rings, multi-channel controllers | Modules tiled end to end |
| Typical processes | Lens coupling, catheter bonding, component fixing, MEMS packaging | Coating, printing, display lamination, conformal coating, potting |
| Automation | Mounted on dispensing/alignment equipment | Mounted on conveyors/presses |
Light delivery for spot curing
- Liquid light guide: single point, economical.
- High-power fiber light guide: 2–4 legs with equal output per leg, one system cures several points.
- Cure ring: couples to a light guide for 360° illumination of cylindrical parts such as catheters.
- LED head with interchangeable lens: 3 mm for peak irradiance, 6–12 mm for larger spots, 5 mm cylindrical lens for a line.
Tiling area curing modules
Excelitas area modules placed end to end have no energy gap and need no overlap; 375 mm modules build any width, and unused modules can be switched off to save energy.
Related products
Spot: OmniCure LX500 (LED, 2/4 channels), OmniCure S2000 Elite (mercury, multi-leg guides/cure rings). Area: Phoseon air-cooled UV LED — FireEdge (10 mm narrow window), FireJet (20/40 mm window, 75–375 mm long).
FAQ
Q: Four adhesive dots: spot or area?
A: If the dots fit within one window, one area source works; if each needs a different dose or timing, use 4-channel spot curing.
Q: Can area curing handle cylindrical parts?
A: Multi-side placement or part rotation works; small-diameter cylinders (catheters, fibers) are more uniform with a cure ring or fiber reflector unit.
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