2001 Philips DUV35

The DUV35 is a special xenon-metal halide lamp based on the 35 W automotive discharge lamp platform and designed to radiate mostly in the UV-A domain of the spectrum. Key changes over the standard white-light lamp include the removal of the UV-block outer jacket, a reduced xenon pressure, and a fill chemistry of iron and cobalt iodides, a mix traditionally used in Philips’s HPA lamps. These modifications result in a 53 % lower lumen efficacy (42.9 vs. 91.4 lm/W initial level) and in a useful service life reduced to 500 h specified at 90 % UV output, and 2 kh at 70 %.

Although this UV source has similar electrical characteristics as those of its automotive counterpart, the usual high-current fast run-up mode is not advised here. Running this lamp at higher-than-nominal current, even briefly, has a very negative impact on its useful life due to the impact of the iron-cobalt fill chemistry and the reduced xenon pressure on the electrode operation. However, the lamp can still be hot restruck, so the DUV35 was usually operated with a basic automotive lamp driver having a modified software flashed in to excludes the fast run-up mode.

Due to the lack of a UV-block jacket the lamp's spectral output extends down to 200 nm, with an optical power output of 4.5, 0.8, and 0.37 W in the UV-A, -B and -C domains, respectively. The broad emission spectrum thus enables a wide variety of applications which include fluorescence, forensic analysis, non-destructive testing, display effects, and glue curing. The lamp can be used in combinations with a reflector and an optical filter in order to project light within a specific spectral band.