US3691453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compact microwave spectrometer
Assignee: AT&T Inc
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Filing: 1970-04-28
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Granted: 1972-09-12
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Expires: 1990-04-28
Abstract
Abstract The development of a simple and inexpensive microwave spectrometer for the study of spin resonance phenomena has been made possible by the inclusion of a solid state microwave energy source within the same resonant cavity as the sample to be investigated. A hypersensitive condition of oscillation of the microwave source has been found which leads to a spectrometer rivaling the sensitivity of much more complex and expensive conventional apparatus. Development models constructed using Gunn type microwave oscillator diodes show that, in addition to the use of conventional microwave detection, the output signal can be detected by observation of the diode bias current, obviating the use of a separate microwave detector.
Inventors
- 👤 Louis William Rupp Jr
- 👤 Walter Michael Walsh Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 01:17
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/60
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
141 words
Method for the investigation of the properties of matter by measurement of the resonant interaction between electromagnetic fields of frequencies greater than 3 x 108 cycles per second and a portion of the matter comprising: a. placing the portion in a resonant cavity, which cavity includes a semiconductor microwave oscillator device as a source of the electromagnetic field; b. applying a variable magnetic field to the portion; c. applying a bias voltage to the semiconductor microwave oscillator device; d. adjusting the bias voltage of said oscillator device to a level at least 5 percent below the level of said bias voltage required to initiate the production of said electromagnetic energy so that said source of electromagnetic energy is oscillating in a hypersensitive state; and e. observing an output signal dependent upon the resonant interaction between the portion and the electromagnetic field.
Claim 2
Dependent Claim
141 words
Method for the investigation of the properties of matter by measurement of the resonant interaction between electromagnetic fields of frequencies greater than 3 x 108 cycles per second and a portion of the matter comprising: a. placing the portion in a resonant cavity, which cavity includes a semiconductor microwave oscillator device as a source of the electromagnetic field; b. applying a variable magnetic field to the portion; c. applying a bias voltage to the semiconductor microwave oscillator device; d. adjusting the bias voltage of said oscillator device to a level at least 5 percent below the level of said bias voltage required to initiate the production of said electromagnetic energy so that said source of electromagnetic energy is oscillating in a hypersensitive state; and e. observing an output signal dependent upon the resonant interaction between the portion and the electromagnetic field.
Claim 3
Dependent Claim
131 words
Apparatus for the investigation of the properties of matter by measurement of the resonant interaction between electromagnetic fields of frequencies greater than 3 x 108 cycles per second and a portion of the matter subjected to a varying magnetic field, said apparatus comprising: a. a resonant cavity for the insertion of the portion; b. a semiconductor microwave oscillator device positioned in said cavity as a source of the electromagnetic field; c. insertion means required to insert the portion within the resonant cavity at a position which is favorable for the interaction of the portion with the electromagnetic field; and d. resonant signal output means including means for the measurement of the variation of the bias current through the semiconductor microwave oscillator device as correlated with the variation of the magnetic field.
Claim 4
Dependent Claim
131 words
Apparatus for the investigation of the properties of matter by measurement of the resonant interaction between electromagnetic fields of frequencies greater than 3 x 108 cycles per second and a portion of the matter subjected to a varying magnetic field, said apparatus comprising: a. a resonant cavity for the insertion of the portion; b. a semiconductor microwave oscillator device positioned in said cavity as a source of the electromagnetic field; c. insertion means required to insert the portion within the resonant cavity at a position which is favorable for the interaction of the portion with the electromagnetic field; and d. resonant signal output means including means for the measurement of the variation of the bias current through the semiconductor microwave oscillator device as correlated with the variation of the magnetic field.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-12 | 1976-03-13 | 1976-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-12 | 1980-03-13 | 1980-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-12 | 1984-03-13 | 1984-09-12 | $7700.00 | Window Closed / Lapsed |