Lab-grade photochemical reactors aren’t the only place where spectral purity matters. On a screen protector line, the same rule applies: if the wavelength drifts or the irradiance isn’t stable, what should be repeatable curing turns into a guessing game. When the photoinitiators in your UV-curable ink get excited outside their sweet spot, cross-linking gets uneven. Adhesion falls off. Optical clarity takes a hit. Out in the real world, that shows up as tacky edges, haze, and lots that don’t make it out of QA. Here’s what actually matters, technically. We build these lamps around a high-pressure mercury vapor discharge, with a dichroic-coated quartz envelope. The output is centered at 365 nm and stays consistent. Peak irradiance hits ≥1200 mW/cm² at a 10 mm working distance, and you can tune total delivered energy density from 500 to 2500 mJ/cm². The reflector is high-purity elliptical aluminum, reflecting over 92% at 365 nm. That keeps the dose on the substrate, not bleeding onto the chamber walls. We match the arc length and focal geometry to the screen-printing frames you’re already running, and for ozone-free operation we use a quartz grade that blocks the 185 nm line. Why this works on screen protector lines. These lines push throughput—1200 to 1800 prints per hour is typical. You need a cure window that keeps pace without overcuring, which makes the film brittle and kills edge adhesion. A stable 365 nm spectrum and a controlled dose profile give you uniform photoinitiator activation across the whole print, even with fine mesh openings and thick ink deposits. Operators see fewer micro-curls, more consistent pencil hardness, and less rework. Power draw is matched to the duty cycle, and the lamp holds output within ±3% over the first 2000 hours, so your process window doesn’t drift. A few things to keep straight. **Match the lamp’s arc length and reflector geometry to your curing station.**Even 2–3 mm of misalignment can drop irradiance by 15–20%. Check the power supply too—ignition voltage and current ramp profile have to line up. Mismatched drivers shorten lamp life and introduce spectral jitter. Keep the quartz sleeve clean and watch operating temperature. Thermal drift shifts the mercury line and changes your dose. Plan replacements around 3000–4000 hours so the output curve stays where it’s supposed to be and your yields stay predictable.