Previously white LEDs had a max of about 60 lumens per watt but the new White LEDs have 135 lumens per watt and match the best lighting alternatives
The new LED can replace traditional fluorescent bulbs for all general lighting applications, and also be used for automobile headlights and LCD backlighting.
Journal of Physics D: Applied Physics - White light emitting diodes with super-high luminous efficacy
With these design improvements and the resulting enhancements in luminous efficacy, the new white LEDs provide further evidence that solid-state lighting can meet a wide variety of our future lighting requirements. Narukawa said that, although these LEDs are expensive compared to commercialized LEDs, he predicts that the price will come down in the future.
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