LED lamps will replace light bulbs in near future

Seems this can be true. Faiz Rahman who is a nano electronics researcher at Glazgow university states that low-energy bright LED light Bulbs are almost here. As matter of fact LEDs are very energy efficient, but fact is that about 70% of electrical energy is converted to light, and only about 20% of it getting out. The rest of light is trapped inside semiconductor due to high refractive index of LED-air surface. But as Faiz says by making LEDs to let more light out their brightness can be compared to ordinary light bulbs. How to make this happen? This can be done by making series of holes on the surface of LED. Rahman has already made several LED prototypes where holes on surface are about 200nm in diameter (400 times narrower than human hair) and 100nm deep. As LED chip is about 0.3×0.3mm there is enough space for hundreds of thousands of holes. This trick with holes actually reduces the LED-air surface refractive index what means less light is reflected back from air to semiconductor. Rahman refers this as “photonic crystal” – an optical nano structure that manipulates light. Such technology allows extracting about 80% of generated light(for times more…

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