US5083028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Individual measuring device for the neutron dose equivalent
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1990-04-03
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Granted: 1992-01-21
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Expires: 2010-04-03
Abstract
Abstract Individual measuring device for the neutron dose equivalent comprising a detector (10) constituted by two identical diodes (13, 14). The first diode (13) is covered by a charged particle neutron converter (16). Converter (16) and the second diode (14) are covered by a protective screen (12). A differential measurement is performed between the signals from the two diodes (13, 14), which makes it possible to eliminate spurious noise. The result of the subtraction is multiplied by a given coefficient to obtain the neutron dose equivalent. Application to radiation protection.
Inventors
- 👤 Jean-Louis Decossas
- 👤 Jean-Claude Vareille
- 👤 Jean Barthe
- 👤 Guy Portal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:10
CPC Classifications
G; G01; G01T; G01T3/00; G01T3/08; G01T1/00; G01T1/02; G01T1/026
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
147 words
Individual device for measuring the neutron dose equivalent comprising: (A) a detector having a first diode, a second diode identical to the first diode, the two diodes being juxtaposed, a converter for converting neutrons into charged particles covering the first diode and a neutron-transparent screen covering the converter and the second diode, said screen protecting the converter and the second diode from charged particles coming from the exterior of the detector, (B) a differential system connected to the two diodes and supplying as an output a digital differential signal which has a value substantially proportional to the dose equivalent due to the neutrons having penetrated the converter, (C) a multiplier connected to the output of the differential system and which multiples the differential signal by a determined coefficient and which supplies as an output a digital signal representing the dose equivalent and (D) an electric power supply.
Claim 2
Dependent Claim
147 words
Individual device for measuring the neutron dose equivalent comprising: (A) a detector having a first diode, a second diode identical to the first diode, the two diodes being juxtaposed, a converter for converting neutrons into charged particles covering the first diode and a neutron-transparent screen covering the converter and the second diode, said screen protecting the converter and the second diode from charged particles coming from the exterior of the detector, (B) a differential system connected to the two diodes and supplying as an output a digital differential signal which has a value substantially proportional to the dose equivalent due to the neutrons having penetrated the converter, (C) a multiplier connected to the output of the differential system and which multiples the differential signal by a determined coefficient and which supplies as an output a digital signal representing the dose equivalent and (D) an electric power supply.
Claim 3
Dependent Claim
150 words
Device according to claim 1, wherein the differential system comprises: a first preamplifier for supplying as an output pulse signals, a second preamplifier for supplying as an output pulse signals, a first discriminator connected to the output of the first preamplifier and only supplying as an output ones of the pulse signals from the first preamplifier whose amplitude exceeds a threshold, a second discriminator connected to the output of the second preamplifier and only supplying as an output ones of the pulse signals from the second preamplifier whose amplitude exceeds said threshold, a first counter connected by a first input to the output of the first discriminator, by a second input to the output of the second discriminator, and supplying as an output the differential signal resulting from a subtraction between the number of pulses counted on the first input and the number of pulses counted on the second input.
Claim 4
Dependent Claim
23 words
Device according to claim 1 comprising a display system connected to the output of the multiplier for displaying the measured neutron dose equivalent.
Claim 5
Dependent Claim
27 words
Device according to claim 1 comprising an alarm system connected to the output of the multiplier and triggered when the neutron dose equivalent exceeds a fixed threshold.
Claim 6
Dependent Claim
104 words
Device according to claim 1 comprising a second counter connected by a first input to the output of the first discriminator and by a second input to the output of the second discriminator, said second counter counting down, from a predetermined initial value, each pulse received on its first input and counting up for each pulse received on its second input, said second counter supplying on one output a zero passage or zeroing signal and reassuming the initial value after each zero passage, and a second detector connected to the output of the second counter triggered at each zero passage of the second counter.
Claim 7
Dependent Claim
18 words
Device according to claim 1, wherein the power supply supplies a d.c. voltage between 2 and 100 V.
Claim 8
Dependent Claim
30 words
Device according to claim 1, wherein the diodes have a depletion range between 10 and 100 micrometers, when they are reverse biased by a voltage between 2 and 100 V.
Claim 9
Dependent Claim
24 words
Device according to claim 1, wherein the diodes have an effective cross-section for the neutrons of at the most 10 -28 m 2 .
Claim 10
Dependent Claim
12 words
Device according to claim 1, wherein the diodes operate at atmospheric pressure.
Claim 11
Dependent Claim
19 words
Device according to claim 1, wherein the screen comprises a material chosen from among aluminium 27 and natural aluminium.
Claim 12
Dependent Claim
16 words
Device according to claim 9, wherein the screen has a thickness of at least 2 mm.
Claim 13
Dependent Claim
30 words
Device according to claim 1, wherein the converter comprises a hydrogenated material implanted with atoms having an effective cross-section for the neutrons of at least 10 -25 m 2 .
Claim 14
Dependent Claim
11 words
Device according to claim 12, wherein the hydrogenated material is polyethylene.
Claim 15
Dependent Claim
16 words
Device according to claim 12, wherein the converter is between 20 micrometres and 1 mm thick.
Claim 16
Dependent Claim
22 words
Device according to claim 12, wherein the atoms are implanted with a density between 10 12 and 10 18 atoms/cm 2 .
Claim 17
Dependent Claim
19 words
Device according to claim 12, wherein the atoms are implanted at an implantation depth between 0.1 and 0.5 micrometer.
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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) | 1995-01-20 | 1995-07-22 | 1996-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-20 | 1999-07-22 | 2000-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-20 | 2003-07-22 | 2004-01-21 | $7700.00 | Window Closed / Lapsed |