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3000 BCE
candle
Although the first candles were created over 5,000 years ago candles got modernized overtime
In the 13th century candle making using Beeswax became a well known art in England and France
In Colonial times Women extracted the wax from Bayberries to use as wax for candles
In the 9th century several types of waxes were developed such as Stearin wax and Paraffin -
Arc Lamps
Generates an electrical spark between 2 carbon rods
Precise gap creates brighter flames
Produced UV rays
The longest rods had to be replaces every 75 days
Created a constant buzzing sound -
Incandescent light bulb
First created by Thomas A. Edison
Light produced by heating of filament
Filament made of tungsten
Contains inert gas which helps to emit light better
Consumes less energy and is cheaper to make than the arc lamp -
Halogen light bulb
Developed by Elmer Fridrich and Emmet Wiley
Uses Halogen like Iodine and Bromine to lengthen the life of the tungsten
It’s halogens have better distributes atoms so the illumination is better and it covers a longer distance -
CFL (Compact Fluorescent lights)
Invented by Edward Hammer
Takes 25% less energy than Halogen light bulbs
A current containing Argon and Mercury is contained in a bent tube
The tube is coated with phosphor on the inside
When an electrical current passes -
Light Emitting Diodes (LED’s)
They use semiconductors such as gallium Arsenide to emit light
Consists of a bunch of smaller lights that emit light in one direction grouped together to emit a larger ray of light
Illuminated by the movement of semiconductor electrons -
Laser lighting
Can produce 200 lumens per watt which doubles the efficiency of LEDs
The CRI exceeds 0.95 which means it will do a better job than LED’s at exposing the true color of objects
A 5 watt laser lamp would be equivalent to a 60 wat light bulb
Laser lamps would be very compact and easier to produce than LED’s which means a higher efficiency for less money
