The LED’s Dark Secret

Solid-state lighting won’t supplant the lightbulb until it can overcome the mysterious malady known as “droop”

14 min read
Illustration: Bryan Christie Design
Illustration: Bryan Christie Design

The blue light-emitting diode, arguably the greatest optoelectronic advance of the past 25 years, harbors a dark secret: Crank up the current and its efficiencies will plummet. The problem is known as droop, and it’s not only puzzling the brightest minds in the field, it’s also threatening the future of the electric lighting industry.

Tech visionaries have promised us a bright new world where cool and efficient white LEDs, based on blue ones, will replace the wasteful little heaters known as incandescent lightbulbs. More than a dozen countries have already enacted legislation that bans, or will soon ban, incandescent bulbs. But it’s hard to imagine LEDs dislodging incandescents and coming to dominate the world electric lighting industry, unless we can defeat droop.

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A water heater in a basement with a fusebox and blue tool box.
iStockphoto

This article is part of our exclusive IEEE Journal Watch series in partnership with IEEE Xplore.

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Master Bond

This is a sponsored article brought to you by Master Bond.

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