You can freely build on How the First Laser Was Invented
This patent expired in 1978. Every claim — 0 independent, 0 dependent — is now unenforceable. Anyone can use, reproduce, manufacture, sell, or offer for sale this technology without a license.
Original assignee
Bell Telephone Laboratories Inc
Patent granted
1960
Expired
1978
Forward citations
145
What this patent covers
This patent describes the transition from masers, which amplify microwaves, to optical masers, which we now call lasers. It details the use of a resonant cavity with reflective ends to trap light, allowing it to bounce back and forth through an active medium. This process stimulates the emission of more light, creating a highly focused, single-color beam. It essentially provides the blueprint for using light as a precise tool for communication and energy transmission.
What is now free to use
All 0 claims of US 2929922 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 semiconductor materials for lasers, which were developed later.
Does not cover fiber optic cables themselves, only the light-amplification device.
Does not cover non-resonant methods of light amplification.
Who is building on this today
Every major telecommunications company, including AT&T and Verizon, relies on the principles established here for global data transmission. Modern laser manufacturers like Coherent and IPG Photonics continue to refine the high-power applications of this original design.
Products built on expired version of this technology
Fiber optic communication networks
Laser eye surgery
Barcode scanners
Laser pointers
How to cite this patent in your documentation
Bell Telephone Laboratories Inc. US Patent 2929922. Masers and maser communications system. Granted 1960, expired 1978. 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.