Some Lumileds LEDs have an extrapolated L70 lifetime of 114 years

April 11, 2017
Lumileds is also proud of the fact that it was the first LED company to share its LM-80 (lumen depreciation) test data.
Lumileds' Luxeon MX multi-die LED emits 1200 lm at a 150 lm/W efficiency (and can do this at 85°C), enabling a system efficiency, which includes optics and such, of 120 lm/W. (Image: Lumileds)

LED maker Lumileds (San Jose, CA), which is the company that first came up with lumen-maintenance testing for LEDs in 2008, today (April 11, 2017) let it be known that it is the only company that has met the premium specifications of the DesignLights Consortium (DLC) in four main product families.

Some of Lumileds' manufacturing and testing processes that the company says it has been improving over the years include: epitaxy, new phosphor development, die fabrication, and in-situ process control, with more than 3 billion device-hours of testing under its belt.

LED lifetimes
Because lighting LEDs tend to wane in output over time rather than burn out like an incandescent bulb, their lifetime specifications take this into account. When an LED is new, it will have an output of a certain number of lumens. This number of lumens gradually decreases; at the time when the LED output has waned to 90% of its original lumens, the LED is said to have reached its L90 lifetime. Similarly, at 70% of its output, the LED has reached its L70 lifetime, and 50% of its output defines its L50 lifetime.

The lighting LED industry has taken the L70 lifetime as its standard. In contrast, the L90 standard is much stricter. Even so, many of Lumileds' LED products demonstrate L90 times in excess of 100,000 hours (the DLC Premium requirements are a mere 36,000 hours).

This is great, but what happens if we relax the L90 criterion to the L70 industry standard and apply it to Lumileds' LEDs? Well, Lumileds says that a range of its LEDs exceeds an extrapolated L70 lifetime of 1,000,000 hours.

114 years
But why is this an extrapolated rather than a measured figure? The simple answer is that 1,000,000 hours is about 114 continuous years of operation -- or far longer than the LED industry has existed. So Lumileds has to characterize the much smaller decrease in output of its longest-life LEDs and extrapolate that data to find the L70 lifetime figure.

For more info, see

Source: Lumileds

Continue Reading

Sponsored Recommendations

Manufacturing thin films with tailor-made electronic properties

Dec. 5, 2023
Unlock the future of optoelectronics as researchers at Leibniz IPHT in Jena, Germany unveil an innovative technique for precision deposition of thin organic semiconductor films...

Quantitative Microscopy with Deep Learning

Dec. 5, 2023
Explore the untapped potential of deep learning in video microscopy with our cutting-edge software, DeepTrack 2.2. Overcoming the steep learning curve, this innovative application...

Stimulated Brillouin scattering enhances CMOS chip for microwave signal processing

Dec. 5, 2023
University of Sydney Nano Institute researchers are pioneering photonic silicon chips and helping spur growth in Australia’s semiconductor industry.

Current Trends in Laser Absorption Spectroscopy: More than Just Beer's Law

Dec. 5, 2023
Dive into the cutting-edge world of absorption spectroscopy in our upcoming webinar, exploring groundbreaking techniques such as cavity ringdown spectroscopy, photoacoustic spectroscopy...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!