1. Incandescent Filament Lamp
Joseph Swan (1847)
Patent By J. W. Starr (1845)
“The application of continuous metallic and carbon conductors, intensely heated by the passage of a current of electricity, to the purpose of illumination”
Thin Sheet Of Platinum Foil
Torricellian Vacuum
Disliked The Use Of A Platinum Filament
Carbon Filament In A Vacuum Appealed To Him
Incandescent Strip Of Carbon - 0.2” Wide, 1.5” Long

2. Incandescent Filament Lamp
Joseph Swan
Publicly Displayed
December 18, 1878
Not In Operation
Never Patented Idea
Though Idea Was Anticipated & thus, Not Patentable
Carbon Filament

3. Incandescent Filament Lamp
Joseph Swan
First Successful Filament Lamp (1881)
Carbon Filament
Thickened Filament Ends
Evacuated Glass Bulb
Platinum Filament Supports
Glass Supports For Filament Holders
Platinum End Wires
Exhausting “Pip”
Applied For Patent
November 27, 1880

4. Incandescent Filament Lamp
Thomas Alva Edison ( )
Initially
Lamp Filaments From Carbon Impossible
Thought He Was Successful With Platinum
Switched To Carbon (1879)
Successful February, 1880
Applied For Patent ????????
Developed Ideas For Commercializtion
Joined With Swan To Form
Ediswan Electric Co.

5. Incandescent Filament Lamp
Edison Carbon Filament Lamp (1881)
Edison Carbon Filament Lamp (1882)
Edison Lamp Cluster (1884)