11 October 2011
Osram red LED prototype breaks 200lm/W efficiency barrier
Osram Opto Semiconductors GmbH of Regensburg, Germany says that its R&D lab has achieved a record electro-optical efficiency of 61% for a red high-power LED. The 1mm2 chip housed on a laboratory package emits at a wavelength of 609nm (λ-dom) and has achieved a record luminous efficiency of 201lm/W at an operating current of 40mA. At a typical operating current of 350mA its luminous efficacy is still 168lm/W, so even at this high wattage more than half of the electrical energy is converted into light.
The increase in output was achieved using a chip with the latest generation of the firm’s own thin-film technology.
Graphic: Record luminous efficacy of 201lm/W and wall-plug efficiency of 61%.
Osram says that LED color mixing systems such as the firm’s Brilliant Mix concept are the latest trend, particularly for general illumination applications. Such systems enable any kind of white light to be produced, from warm white through neutral white to daylight white. The overall system performance is as good as the individual components will allow. Osram says that its new red high-power LED promises a further improvement in the quality of light with lower power consumption, especially in warm white. This should benefit not only color mixing concepts but also all applications that use high-efficiency red LEDs – in the general illumination, projection and automotive sectors.
Higher efficiency means more light from the same amount of electricity, which in turn means lower power consumption for a particular application. Because fewer chips are needed to produce the same brightness, designers will have greater freedom, says Osram Opto. Light sources can be made smaller while still producing the same brightness.
“The results of this project can be extended to all the wavelengths in aluminum indium gallium phosphide (AlInGaP) chip technology, so we anticipate a boost in efficiency in these light colors – even at 660nm, which is the wavelength needed for plant lighting for example,” says Dr Martin Behringer of Osram Opto’s LED development team. “Probably we will be introducing the results of this development project across the entire wavelength spectrum into production in about a year’s time,” he adds.