US3614646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photomultiplier tube agc using photoemitter-sensor for dynode biasing
Assignee: Unisys Corp
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Filing: 1967-10-18
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Granted: 1971-10-19
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Expires: 1987-10-18
Abstract
Abstract A photomultiplier tube automatic gain control circuit wherein the biasing potentials between a plurality of adjacent dynodes are varied inversely as the amplitude of the photomultiplier output signal. The output signal is detected and applied to a photoemitter-sensor connected in shunt with the biasing network for the aforesaid dynodes.
Inventors
- 👤 Earl T Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:14
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3084; H01; H01J; H01J43/00; H01J43/04; H01J43/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
82 words
An automatic gain control circuit for a photomultiplier tube having a multiplicity of dynodes, said circuit comprising a source of current, an impedance network connected across said source for biasing said dynodes, a photoconductor resistor connected across a portion of said network for biasing a plurality of adjacent dynodes, a lamp for illuminating said resistor, and means for detecting the long-term amplitude variations in the current flowing through said photomultiplier tube, said means being connected between said photomultiplier tube and said lamp.
Claim 2
Dependent Claim
82 words
An automatic gain control circuit for a photomultiplier tube having a multiplicity of dynodes, said circuit comprising a source of current, an impedance network connected across said source for biasing said dynodes, a photoconductor resistor connected across a portion of said network for biasing a plurality of adjacent dynodes, a lamp for illuminating said resistor, and means for detecting the long-term amplitude variations in the current flowing through said photomultiplier tube, said means being connected between said photomultiplier tube and said lamp.
Claim 3
Dependent Claim
19 words
An automatic gain control circuit as defined in claim 1 wherein said impedance network is a resistor bleeder network.
Claim 4
Dependent Claim
31 words
An automatic gain control circuit as defined in claim 1 wherein said photoconductor resistor is connected across a central portion of said network for biasing a central plurality of adjacent dynodes.
Claim 5
Dependent Claim
72 words
An automatic gain control circuit as defined in claim 1 wherein said photomultiplier tube has a cathode and an anode and further including an impedance means, one end of said impedance network being connected to said cathode, said impedance means being connected between said anode and the other end of said impedance network, and said source being connected between said cathode and the junction of said impedance means and said impedance network.
Claim 6
Dependent Claim
26 words
An automatic gain control circuit as defined in claim 4 wherein said impedance network is a resistor bleeder network and said impedance means is a resistor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |