Incandescent light bulb
Thomas Edison receives U.S. Patent No. 223,898 for an electric lamp
View full image ↗ How was this image made?
The creative brief sent to the image model. These are instructions, not a record of what actually happened.
Original prompt & settings (JSON) ↗The patent's goal was not merely a glowing wire: it explicitly sought enough resistance to divide electric light among many lamps at once.
27 January 1880: “Electric Lamp”
On 27 January 1880 the United States Patent Office issued Thomas A. Edison Patent No. 223,898, titled “Electric Lamp.” The application had been filed on 4 November 1879, following his Menlo Park group's October experiments with carbonized cotton thread.
Edison now held an issued U.S. patent covering specified carbon-filament lamp constructions and manufacturing methods.
What the claims covered
The patent described a high-resistance carbon filament in an evacuated glass receiver, with conductors passing through the glass and methods for joining the carbon to platinum contact wires. The specification proposed carbonizing such ordinary materials as thread, paper, and wood splints inside a closed chamber.
Its aim was systemic: high resistance was what made it possible to subdivide electric light among many lamps on one circuit. The document repeatedly envisioned a coiled filament, although the familiar early Edison lamps commonly displayed a horseshoe shape.
What it did not cover
This was not a patent on the abstract idea of electric light, nor on every possible incandescent bulb; its claims described particular filament, receiver, conductor and manufacturing arrangements. Edison did not invent incandescence or build the first experimental incandescent lamp.
Nor did the grant commercialize anything by itself. Filament development and the construction of a complete lighting system continued afterwards, and Edison's surviving laboratory record does not show bamboo tests until months after this patent was granted.
Sources
Researched 23 Aug 2026 5 sources 3 audit passes
How this was checked
Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →