From Twinkling of Fireflies to LED - more on Green Light,the Millennium Light!
Twinkle Twinkle little stars. NOW I WONDER WHERE YOU ARE?? Leave aside stars; on a clear night in urban
India you do not even get glimpses of fireflies nowadays. Vanished! Magician –
Artificial Light Pollutant. Lighting professionals all over the world are relentless
in their effort to relive the olden days of mystical star gazing experience on
clear nights. The solution lies in LED as light source in general lighting.
Reason being it is a tiny light source and thus can be optically controlled in
a highly effective manner. Imagine a stadium lit by LED floodlight or all major
thoroughfares in a city lit by LED streetlights. No untoward upward light, no glare,
no pollution. LED is here and has progressed at a furiously rapid pace since
the dawn of this millennium. Recently, scientists inspired by the twinkling of
fireflies have modified LED to make it almost one and a half time more
efficient than the original. Fireflies are bioluminescent insects and the
organs on their abdomens flash light in order to attract their mates. A
chemical reaction in photocytes (specialized cells in fireflies) creates light.
This light is then emitted through cuticle( a part of the insect’s exoskeleton).Mismatch in
light travel which is slower in cuticle compared to air normally dims the glow
as a proportion of light is reflected back into the photocytes. Researchers observed that specimens
of fireflies found in Latin America and the United States have unique surface
geometry of cuticles. The jagged scales resembling factory roof improve light
extraction manifold and minimize internal reflections. This discovery led
scientists to develop effective LED coating which could produce more efficient
and brighter light output.
|
This image taken from LED Professionals show:
The misfit scales(bottom right) found on the lantern
of the Photuris firefly (top right) are the inspiration for a GaN LED, coated
with a "factory-roof" pattern (left) that increased light extraction
by more than 50 percent
|
Credits: The article was originally
released on the www.osa.org
website.
Reference:
LED Professionals.
Comments
It's very nice of you to share your knowledge through posts. I love to read stories about your experiences. They're very useful and interesting. I am excited to read the next posts. I'm so grateful for all that you've done. Keep plugging. Many viewers like me fancy your writing. Thank you for sharing precious information with us. Best bathroom ceiling light fixtures service provider