Osram increases green LED efficiency for wearables

May 11, 2018 // By Julien Happich
The significant drop in light output (green gap phenomenon) exhibited by green LEDs has often been the cause of efficiency problems and high costs in customer applications.

For its indium gallium nitride (InGaN)-based green LEDs, Osram Opto Semiconductors has now succeeded in reducing the typical forward voltages by around 600mV to 2.6V at power densities of 45 A/cm 2. With a simultaneous increase in optical output power, customers instantly benefit from improvements in efficiency of up to 40 percent compared to predecessor products across the entire UX:3 portfolio from Osram. The benefits are considerable, particularly for applications in which red, blue and green LEDs are used in combination. Because all three colors now have a voltage of less than 3V the drivers, which were previously designed for higher maximum voltages, can now be dimensioned smaller. This in turn reduces both dissipative power loss and costs. At 350mA, 1mm 2 UX:3 chips achieve efficiencies of 175lm/W and higher at wavelengths around 530nm with the new technology. Absolute light output in excess of 300lm at a pumping current of 1A opens up new applications for customers.

Osram - www.osram.com


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