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US 3388314Freedom to Build
Public domain since 1987

You can freely build on Gordon Gould's Early Concepts for High-Frequency Radiation Devices

This patent expired in 1987. 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

Control Data Corp

Patent granted

1968

Expired

1987

Forward citations

53

What this patent covers

The patent details apparatus designs for generating electromagnetic radiation at frequencies significantly higher than visible light, specifically targeting the ultraviolet and X-ray spectrums. It describes using a gas discharge or similar excitation mechanism to create a population inversion, which allows for the stimulated emission of radiation. By utilizing optical cavities or resonant structures, the device forces this radiation to amplify into a coherent beam, effectively extending the principles of the laser into higher energy regimes.

What is now free to use

All 0 claims of US 3388314 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 standard visible-light lasers operating at lower frequencies.

    • Does not cover specific medical imaging applications or diagnostic X-ray machines.

    • Does not cover solid-state semiconductor laser diodes.

    Who is building on this today

    Research institutions and national laboratories continue to explore high-energy radiation sources for fusion energy and advanced lithography. Companies like ASML utilize extreme ultraviolet light technology that builds upon the fundamental physics of coherent radiation generation.

    Products built on expired version of this technology

    Experimental X-ray lasers

    High-energy ultraviolet light sources for lithography

    How to cite this patent in your documentation

    Control Data Corp. US Patent 3388314. Apparatus for generating radiation of frequencies higher than those of light. Granted 1968, expired 1987. 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.

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