LED Lighting Technology

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LED Lighting Technology

• By Dan Kaser
• 9/17/2007

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What Are LEDs?

• LED is an acronym for Light Emitting Diode
• Instead of a filament they use a semiconductor
  diode which emits narrow-spectrum light.
• Depending on the composition condition of the
  semiconducting material used (Silicone,
  germanium), they come in either Infrared for
  sensing heat, Visible for every day use, or
  Near-Ultraviolet for spotting stains at a
  crime-scene.
• An LED consists of a chip of semiconducting
  material that has been doped with impurities in
  order to create a p-n junction.
• A p-n junction is basically a junction between an
  anode and a cathode.
• Current flows easily from the p-side to the
  n-side, but never in the reverse order.
• The wavelength and color of the LED depends on
  the band-gap energy of the materials forming the
  p-n junction.

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Where do we see LEDs?

• Everywhere!!

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Current uses of LEDs

• Status indicators on all sorts of equipment your
  cell phone, computer, monitor, stereo
• Traffic lights
• Architectural lighting
• Exit signs
• Motorcycle and bicycle lights
• Railroad crossing signals
• Flashlights
• Emergency vehicle lighting
• Message displays at airports, railways, bus
  stations, trams, trolleys and ferries
• Military and Tactical missions utilize red and/or
  yellow lights to retain night vision.
• Movement sensors
• LCD backlighting in televisions
• Christmas Lights
• Lanterns

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LEDs Vs. Incandescents

• Incandescent
• Positives
• Cheap to manufacture buy
• Easier to come by
• Generally stronger light output
• Better for seeing through Fog and Smoke
• Negatives
• VERY breakable
• Horrible patterns in light
• Hot burning
• Heavy on battery consumption
• Short lifespan
• Yellowish color filters out anything with yellow
  in it, IE White looks yellow, yellow doesnt
  show, red looks brown, green looks black.

• LED
• Positives
• Virtually indestructible
• 100,000 hour lifespan
• Low energy consumption
• Symmetrical beam with little-to-no artifacts
• Cheap to manufacture
• Available in a multitude of colors without
  requiring a filter.
• Pure white light means no color will be filtered
  out.
• Low functioning temperature
• Negatives
• Less potential output (for now)
• Slightly more expensive to purchase

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Potential uses in the future

• LEDs are already being used in tail-lights for
  cars, and some companies like Lexus are
  experimenting with LED headlights
• Home lighting Imagine a light-bulb with
  100,000 constant hours of use. In other words
• 100,000 hours/24 hours a day 4,166 days
• 4,166 days/365 days a year 11.4 years.
• Not only will the light bulb last for 11.4 years,
  but it will also require much less current than a
  traditional light-bulb. If one LED-light bulb
  requires half the energy of one Incandescent
  light-bulb, we may not have to suffer through
  rolling blackouts ever again!
• LEDs are already getting brighter. Here is an
  example of one of the most recent LEDs to hit
  the market titled the Luxeon Rebel. It is both
  twice as bright, and uses half the current of
  its predecessor of only 2 years.
• Technology will eventually dictate that LEDs are
  the light source of the future.

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How will this affect the business world?
Impact of LEDs on the world of Business

• With the horizons of LED technology broadening,
  many light manufacturers are putting their top
  scientists to work
• Maglite, for instance, always made Incandescent
  lights, but have recently begun creating drop-in
  LED modules for their incandescent torches.
• If one car company comes out with LED headlights
  that manage to function at a higher efficiency
  and also increase output, it is inevitable that
  all other car companies will follow. Nobody
  likes a burnt out headlight!
• Energy is an expensive commodity! The more money
  we can save on energy, the more money we can
  spend on more important business aspects. One
  office building that solely uses LED bulbs could
  save thousands a year in Energy use alone.
• When the sun explodes we wont be able to make
  anymore energy and we will have to rely on LEDs
  and their efficiency to find food in the pitch
  black.

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THE END!