LED

LIGHTING

TECHNOLOGY

What Are LED’s?

• 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 everyday 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.

Where do we see LED’s?

Everywhere!!

Current uses of LED’s

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

LED’s Vs. Incandescent

Incandescent

Positives

• Cheap to manufacture &

buy

• Easier to come by

• Generally stronger light

output

• Better for seeing through

Fog and Smoke

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

• 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

doesn’t show, red looks brown,

green looks black.

Negatives

• Less potential

output (for now)

• Slightly more

expensive to

purchase

Potential uses in the future

• LED’s 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!

• LED’s are already getting brighter. Here is an example

of one of the most recent LED’s to hit the market titled

the “Luxeon Rebel”. It is both twice as bright, and uses

half the current of it’s predecessor of only 2 years.

• Technology will eventually dictate that LED’s are the

light source of the future.

Impact of LED’s on the world of Business

• With the horizons of LED technology

broadening, many light manufacturer’s 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 won’t be able to make anymore

energy and we will have to rely on LED’s and

their efficiency to find food in the pitch black.

THE END