On the PCB floor, a misaligned or under-cured solder mask doesn’t just look off—it can short a 100 µm trace. It’s not enough to simply hit a UV dose; you need the right spectrum, delivered where it matters. That’s why we built our UV gallium lamp for PCB exposure around that reality. What matters under the hood We hold a tight 365 nm peak with a narrow spectral bandwidth, matched to the photoinitiator absorption in solder mask inks. Peak irradiance stays above 1,200 mW/cm² at the arc distance used in your exposure unit, so you get the photon flux needed for fast cross-linking. Output stays stable thanks to a low-decay arc tube—we’ve run units for 5,000+ hours with under 5% irradiance drop. The reflector uses a dichroic coating to knock out IR and keep the spectrum consistent, so the energy density across the substrate stays repeatable. Why it plays in fine-line territory When traces are this fine, there’s no room for a half-cure between lines. The 365 nm output gives you deeper penetration with lower surface heat, so you get full adhesion without thermal stress or mask bridging. The payoff shows up as higher yield on HDI and rigid-flex boards, a consistent surface finish, and fewer reworks. You can run faster cycles without sacrificing cure depth, and because lamp output stays steady, exposure settings don’t drift over long production runs. A few shop-floor details Match lamp power and arc length to your exposure frame and optics. If the system is undersized, you end up chasing dose by slowing down throughput. Go ozone-free in the design, and make sure your shutter and airflow line up with the lamp’s thermal profile to avoid hot spots. And yes, confirm compatibility with your spectral radiometer and dosimetry—repeatable curing depends on disciplined measurement.