Warren De la Rue created a lamp that worked but was to expensive for wide-spread use.
Edward Shepard invented an electrical incandescent arc lamp using a charcoal filament.
German Henricg Globel created the first true light bulb –used a carbonized bamboo filament inside a glass bulb.
Herman Sprengel invented the mercury vacuum pump –Made it possible to get a good vacuum inside a bulb.
Henry Woodward and Matthew Evans patented a light bulb.
Sir Joseph Wilson Swan invented a light bulb that lasted for 13.5 hrs. –used a carbonized cotton filament.
Thomas Alva Edison invented a light bulb that burned for 40 hrs. –placed filament in an oxygen-less bulb. –His ideas were based on the 1875 patent he purchased from Henry Woodward and Matthew Evans.
Edison continued to improved his light bulb until it could last for over 1,200 hours –Used a bamboo-derived filament.
Willis Whitnew invented a filament that would not make the inside of a light bulb turn dark. –Used a metal-coated carbon filament
The General Electric Company patented the use of tungsten filaments for use in light bulbs. –These filaments were expensive.
William David Coolidge invented an improved method of making tungsten filaments. –outlasted other types of filaments –made costs practical.
The first frosted light bulbs were produced.
Philips Company invented a light bulb that lasts 60,000 hours.
