Incandescent light bulb
device · 1879 · Electric age
Light from a filament heated by current. Lodygin, Swan and Edison worked on it.
Inventors: Thomas Edison, Joseph Swan, Alexander Lodygin, Alessandro Volta.
What it is made of
- Tungsten filament — has part. A tungsten coil heated by current.
- Glass light bulb envelope — has part. A glass bulb with a vacuum or inert gas.
- Screw lamp base — has part. A screw contact (the Edison base).
Principles and materials it uses
- Joule heating — uses. The filament is heated by current until it glows.
- Vacuum — uses. The bulb was evacuated so the filament would not burn out.
- Tungsten — is made of. A tungsten filament (since 1904–1910).
- Glass — is made of. The glass bulb keeps a vacuum or inert gas so the filament does not burn out.
Where it is used
- Torch (flashlight) — is part of. A bulb (today an LED).
- Film projector — is part of. The light source (formerly an arc).
History: what it evolved from and what it influenced
- Oil lamp — evolved from. The electric lamp replaced oil and gas lamps.
- Gas lamp — evolved from. Electricity displaced gas lighting.
- LED lamp — evolved into. It replaced incandescent bulbs.
What it is a kind of
- Halogen lamp — includes. An incandescent lamp.
Things built in a similar way
- Heating element — works like. A lamp and a heater use the same effect — a conductor heated by current; they differ in purpose, light or heat.