You can freely build on How Georges Claude Invented the Neon Light

What this patent covers

The patent details a method for creating electric light by sealing neon gas inside a glass tube with electrodes at each end. When high-voltage electricity flows through the gas, it ionizes the neon, causing it to glow with a characteristic bright red-orange light. The invention specifically addresses the purification of the gas and the design of the electrodes to prevent the gas from being absorbed into the glass walls during operation, which was a major hurdle for early gas-discharge lamps.

What is now free to use

All 0 claims of US 1125476 are in the public domain. Specifically:

The 0 dependent claims add narrowing limitations and are also free.

What is NOT covered

Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.

• Does not cover the use of gases other than neon for illumination

• Does not cover modern LED-based signage that mimics the look of neon

• Does not cover low-voltage lighting systems

Who is building on this today

While the original neon tube industry has largely been superseded by LED technology, companies specializing in heritage restoration and high-end artistic lighting continue to utilize these fundamental gas-discharge principles.

Products built on expired version of this technology

How to cite this patent in your documentation

Individual. US Patent 1125476. System of illuminating by luminescent tubes.. Granted 1915, expired 1932. Now in the public domain.

Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.

PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.