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Research Corporation maser and laser patents collection, 1956-1962

Description of Collection


American Institute of Physics. Niels Bohr Library & Archives.

Papers created by

Research Corporation.

Size of collection

0.25 linear feet
1 half manuscript box

Short description of collection

Collection of patents that reflect the history of maser and laser development in the 1950s and 1960s.

Language(s) of collection


Collection number:


Biographical Note

The Research Corporation was incorporated in New York in 1912 with the purpose of advancing academic science and technology. It supports research in the natural and physical sciences and evaluates, patents, and licenses academic inventions.

Scope and Contents of Collection

Patents assembled from the files of the Research Corporation which reflect the history of maser and laser development during this period. The collection includes patents by Robert H. Dicke, Lowell E. Norton, Friedrich H. Reder, Charles H. Townes, and others.

Restrictions on Use and Access

Selected Search Terms

These papers have been indexed in the International Catalog of Sources for History of Physics and Allied Sciences (ICOS) using the following terms. Those seeking related materials should search under these terms.


Dicke, Robert H. (Robert Henry)
Norton, Lowell E.
Reder, Friederich H.
Townes, Charles H.


Research Corporation.

Subject terms


Genre terms

Patents (licenses).

Organization and Arrangement of Collection

This collection is organized into a single series:

  • Series I: Patents

Preferred Citation of Collection

Box [number], Folder [number], Research Corporation maser and laser patents collection, 1956-1962. American Institute of Physics, Niels Bohr Library & Archives, College Park, MD 20740, USA.

Administrative Information


Finding Aid to the Research Corporation maser and laser patents collection, 1956-1962


American Institute of Physics Niels Bohr Library & Archives

One Physics Ellipse
College Park, MD 20740


Encoding Information

Machine-readable finding aid encoded by Melanie J. Mueller in 2014. Any revisions made to this finding aid occurred as part of the editing and encoding process.

Series I: Patents

Box 1 Folder 1 Oscillators Employing Microwave Resonant Substance: Relates to generation of phase coherent electrical oscillations; means of utilizing resonance properties of particles not in thermal equilibrium; gaseous medium, microwave frequency output; excitation by pulse excitation., undated
Folder 2 Amplifier Employing Microwave Resonant Substance: Microwave amplifier utilizing a microwave resonant substance as the amplifier element; very similar to number 1; infers gaseous medium but broader in first three claims., undated
Folder 3 Microwave Amplifier Employing a Microwave Resonant Gas as the Amplifying Element: A narrower description of number 2 stating structure of device and use of low pressure gas., undated
Folder 4 Apparatus Utilizing Atomic or Molecular Beams: Device to produce a control signal utilizing effects of magnetic fields upon the spin orientation or angular momentum of atomic, molecular or nuclear particles in a particle beam., undated
Folder 5 Atomic or Molecular Oscillator Circuit: A maser device in which oscillations are sustained by electrical feedback, a two chamber device providing modulation to resonant frequency., undated
Folder 6 Molecular Microwave Translating Apparatus: Relates to molecular translating devices to secure and continuously maintain a microwave resonant gas in a state of non-equilibrium by the application of heat., undated
Folder 7 Tunable Atomic Amplifier or Oscillator: Design similar to number 5 wherein the apparatus is tuned by varying the static and microwave magnetic fields., undated
Folder 8 Molecular Amplification and Generation Systems and Methods: Improvement patent describing apparatus to increase the quantity of gas molecules in the higher of two energy states. Claims on specific design., undated
Folder 9 Amplifiers and/or Generators Employing Molecularly Resonant Media: A maser device which circulates the resonant gas to permit continuous operation at ambient temperatures., undated
Folder 10 Uninterrupted Amplification by Stimulated Emission of Radiation From a Substance Having Three-Energy States: A solid resonating medium with a multiple energy level system, not limited to frequency band; claims oscillator, amplifier and receiver., undated
Folder 11 Three Level Maser: A maser using a composite crystal doped with a paramagnetic salt (various sulphates, claim 2), a magnetic field and means for pumping., undated
Folder 12 Solid State Maser: A maser using a paramagnetic solid with three energy levels; limited to microwave frequencies., undated
Folder 13 Maser: A solid state maser using an endless paramagnetic film continuously excited by magnetic fields to a higher energy level and then fed to the resonant cavity., undated
Folder 14 Nuclear Quadrupole Resonance Devices: A particular electrical arrangement wherein the cavity structure is tuned to the three energy transition frequencies, that is, pumping frequency and the two radiated level transitions., undated
Folder 15 Maser: Similar to number 13 (same inventors)., undated
Folder 16 Superregenerative Maser: Relates to the external circuitry, magnetic fields, pulse and sweep generators, and so forth, used with a maser using gases, liquids or solids for super-regenerative action., undated
Folder 17 Quantum Mechanical Resonance Devices: Improvement patent on Townes’ original NH3 maser, by providing a long path of travel before relaxation occurs., undated
Folder 18 Maser: A solid state maser employing a paramagnetic material having an anisotropic a-value, that is, varying the resonant frequency as a function of the angle that the crystalline axis makes with the magnetic field., undated
Folder 19 Frequency Converter: Similar to number 16 in design; a maser design to convert microwave frequencies to radio frequency or intermediate frequencies., undated
Folder 20 Microwave Devices Employing Quantum Transition Resonance Phenomenon: A maser device to generate particular modes (TE11, TM01 ) of electromagnetic energy., undated
Folder 21 Microwave Maser Amplifier: Improvement patent of microwave amplifier by using isotropic and anisotropic mixture of paramagnetic salts., undated
Folder 22 Solid State Maser Amplifier: Similar to number 11 (one inventor common to both), but with four levels or more selected by relaxation times., undated
Folder 23 Production of Electromagnetic Energy: Townes patent., undated
Folder 24 Automatic Tuning System: Automatic tuning of maser by means of auxiliary circuits which detect a modulation component which produces an error signal when compared to the standard., undated
Folder 25 Molecular Resonance Amplifier: A maser cavity tuned to two frequencies to produce a lower beat frequency., undated
Folder 26 Focusers for Molecular Resonance Devices: An improvement patent dealing with the focusing of the molecular beam in a gaseous maser., undated
Folder 27 Stable Oscillator: An improvement patent relating to number 5 (same inventor) using sustained electromagnetic oscillations to produce subsequent pulses, namely, a self-regenerative stable oscillator., undated
Folder 28 Molecular Beam Focusing Devices: Another focusing device by one the inventors of number 26 relating to the focusing of molecular beams by sloping the focuser., undated
Folder 29 Atomic Resonance Devices: Relates to an atomic, particularly cesium, beam frequency standard which reduces the wasting of the material, particularly cesium, when the device is not in use, and also improves the means of frequency modulating the output, increases the signal-to-noise ratio and decreases the height of the apparatus., undated
Folder 30 Traveling Wave Solid State Masers: Improvement patent relating to a traveling wave, microwave maser which facilitates the simultaneous application of pumping and signal power to a solid state negative resistance material and increases amplification by increasing the transient time., undated
Folder 31 Molecular Beam Apparatus of the Maser Type: Mechanical improvement patent relating to means of supplying gaseous material to a maser., undated
Folder 32 Masers and Maser Communications Systems: Use of a laser for communications., undated
Folder 33 Variable Q Microwave Cavity and Microwave Switching Apparatus for Use Therewith: A variable Q device to be used in a microwave maser to provide stretching and attenuation by means of the avalanche breakdown phenomenon in semiconductors., undated
Folder 34 Stabilization of a Maser Cavity: A circuit for controlling the tuning element of a maser frequency oscillator cavity resonator; somewhat similar to number 25 (same inventor)., undated
Folder 35 Cesium Ovens: Relates to the molecular beam source only (cesium oven) and the design thereof., undated
Folder 36 Maser Type Oscillator: A maser device comprising a body of crystalline material having a plurality of at least four quantum transition energy levels such that energy transitions between said levels are permissible, means for irradiating said body by continuous wave energy of frequency content such as to set up energy transition between the lowest and highest or said levels in a plurality or steps which leave unaffected at least an intermediate one of said levels, and means for selecting the resultant stimulated emission of energy frequency equal to the transition frequency between said highest level and said one intermediate level., undated
Folder 37 Molecular Beam Maser: A device to slow down the molecular beams in a gaseous maser to lengthen the transient time., undated
Folder 38 Process for Growing and Apparatus for Utilizing Paramagnetic Crystals: A process patent relating to a method for growing single crystal tungstate containing paramagnetic ions., undated
Folder 39 Molecular Beam Apparatus: Improvement patent relating to a molecular beam resonant unit which separates molecules or two energy levels into two groups., undated
Folder 40 Solid State Maser: (See numbers 11 and 32) A solid state maser capable of continuous operation employing pumping energy at a frequency substantially lower than the signal frequency., undated
Folder 41 Thermal Maser: A device using a monocrystalline element with three levels that convert heat energy directly to coherent electromagnetic radiation., undated
Folder 42 DC Pumped Solid State Maser: Continually operating maser using Bi, Ar, and Sb as the active element which uses D.C. as the pumping energy source and increases the power handling capacity., undated
Folder 43 Tunable Two-Mode Cavity Resonator: A high Q cavity resonator which through its physical configuration can support two fundamental modes., undated
Folder 44 Optical Maser: Generation of coherent radiant energy by creation of hole-electron pairs in semiconductive wafers. Pumping is accomplished by radiant means or electric currents., undated
Folder 45 Maser, undated
Folder 46 Maser, undated
Folder 47 Microwave Amplifier, undated