US4044261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and system for improving the definition of a scintillation detector
Assignee: Georgetown University
•
Filing: 1976-03-17
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Granted: 1977-08-23
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Expires: 1996-03-17
Abstract
Abstract The definition of a tomographic readout image is highly sharpened and improved by minimizing or eliminating the effects of persisting images in the electronic scintillating circuit resulting from phosphorescent afterglow, by utilizing a special filter network in the detecting circuit.
Inventors
- 👤 James B. Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:05
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/208
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
A system for improving the definition of a scintillation detector comprising a network connected to the detector, the network being constructed and arranged to minimize the effect of a phosphorescent afterglow in the detector, the network has an input and comprises a pair of variable resistors and a capacitor, one of the variable resistors being connected directly across and in parallel with the input, the other variable resistor being connected in parallel with the capacitor, the parallel-connected variable resistor and capacitor being connected in series with the input, and the capacitor having a relatively large capacitance and a low dissipation factor.
Claim 2
Independent Claim
101 words
A system for improving the definition of a scintillation detector comprising a network connected to the detector, the network being constructed and arranged to minimize the effect of a phosphorescent afterglow in the detector, the network has an input and comprises a pair of variable resistors and a capacitor, one of the variable resistors being connected directly across and in parallel with the input, the other variable resistor being connected in parallel with the capacitor, the parallel-connected variable resistor and capacitor being connected in series with the input, and the capacitor having a relatively large capacitance and a low dissipation factor.
Claim 3
Dependent Claim
25 words
A system as set forth in claim 1 wherein the capacitor has a capacitance of about ten microfarads and a dissipation factor of about 0.1%.
Claim 4
Dependent Claim
15 words
A system as set forth in claim 2 wherein the capacitor is a nonelectrolytic capacitor.
Claim 5
Dependent Claim
30 words
A system as set forth in claim 1 wherein the first-mentioned variable resistor has a much greater resistance than the other variable resistor, which is in parallel with the capacitor.
Claim 6
Dependent Claim
32 words
A system as set forth in claim 4 wherein the scintillation detector incorporates a NaI crystal, and the first-mentioned variable resistor has about ten times the resistance of the other variable resistor.
Claim 7
Dependent Claim
33 words
A system as set forth in claim 4 wherein the scintillation detector incorporates a CaF crystal and the first-mentioned variable resistor has about one hundred times the resistance of the other variable resistor.
Claim 8
Dependent Claim
43 words
A system for improving the definition of a tomographic scintillation detector comprising the network set forth in claim 1, wherein the scintillation detector incorporates a NaI crystal, and the first-mentioned variable resistor has about ten times the resistance of the other variable resistor.
Claim 9
Dependent Claim
44 words
A system for improving the definition of a tomographic scintillation detector comprising the network set forth in claim 1, wherein the scintillation detector incorporates a CaF crystal, and the first-mentioned variable resistor has about one hundred times the resistance of the other variable resistor.
References Cited (Backward Citations)
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US3153207A
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US3842278A
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US3942011A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-22 | 1981-02-21 | 1981-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-22 | 1985-02-21 | 1985-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-22 | 1989-02-21 | 1989-08-23 | $7700.00 | Window Closed / Lapsed |