Philips Lumileds of San Jose, CA, USA has launched the LUXEON UV family of LEDs, delivering what are claimed to be the highest system flux densities in the industry. Available with emission wavelengths of 380-430nm, the emitters are specifically designed for applications including ultraviolet curing, counterfeit detection, medical, industrial and specialty lighting.
"The UV LED market has been hampered by limited flux density and a lack of design flexibility," says senior product line manager Kurosh Hashemi. "Philips Lumileds addressed these limitations by introducing a compact, high-power emitter that can be tightly spaced to deliver the highest flux density to the desired medium," he adds. "For example, for curing applications, 395nm emitters enable arrays of up to 38W/cm2 when driven at 1A." With a micro-footprint of only 2.2mm2 [one-fifth the size of other high-power emitters, it is reckoned], each LED is provided in undomed form for precise optical control.
Since the product's inception, Lumileds has optimized LUXEON UV LEDs for high reliability: using surface-mount assembly instead of wire bonding; designing for high-power operation (up to 1A drive currents) with what are claimed to be best-in-class droop and forward voltage; and offering multiple binning options. The LUXEON UV is modeled after the firm's LUXEON Z family. "We combined the proven advantages of high-flux density and optical control of the LUXEON Z design with a high-performing UV chip," says Hashemi.
The LUXEON UV is designed for superior thermal management. The package uses flip-chip assembly, where the chip is in direct contact with the thermally conductive AlN substrate. Customers have shown interest in using air cooling units rather than more costly water cooling, notes Hashemi.
