US5656815A
Expired / Lapsed
US
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Thermoluminescence radiation dosimetry using transparent glass containing nanocrystalline phosphor
Assignee: NAVY United States, NAVY THE, Secretary of
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Filing: 1996-02-08
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Granted: 1997-08-12
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Expires: 2016-02-08
Abstract
Abstract Radiation is detected using a light transparent thermoluminescent dosimeter that comprises a nanocrystalline phosphor dispersed in a light transparent glassy matrix, such as Vycor glass. The dosimeter is placed in an environment in which radiation is present for a period of time, removed from the environment and then heated to emit light, the intensity of which is indicative of the radiation dose. The method of the invention is useful for detecting and recording the dosage of both UV and ionizing radiation. In one embodiment in which the dosimeter is in the form of a flat plate. Ambient α or β radiation populates traps and, upon heating of the flat dosimeter, the emitted light is guided to the edges of the dosimeter by total internal reflection, where it is detected and recorded.
Inventors
- 👤 Brian L. Justus
- 👤 Alan L. Huston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:39
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/02; G01T1/10; G01T1/11
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
84 words
A method for detecting the presence of radiation in an environment in which radiation is present, said method comprising: placing a thermoluminescent radiation dosimeter in said environment for a predetermined period of time, removing said irradiated dosimeter from said environment and then heating said irradiated dosimeter so that it emits thermoluminescent light of an intensity indicative of the absorbed dose and determining the absorbed dose from said emitted light, wherein said dosimeter comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix.
Claim 2
Independent Claim
84 words
A method for detecting the presence of radiation in an environment in which radiation is present, said method comprising: placing a thermoluminescent radiation dosimeter in said environment for a predetermined period of time, removing said irradiated dosimeter from said environment and then heating said irradiated dosimeter so that it emits thermoluminescent light of an intensity indicative of the absorbed dose and determining the absorbed dose from said emitted light, wherein said dosimeter comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix.
Claim 3
Dependent Claim
34 words
A method according to claim 1 wherein said phosphor comprises a phosphor which, when heated after being exposed to ionizing radiation, emits thermoluminescent light, the intensity of which is indicative of the absorbed dose.
Claim 4
Dependent Claim
18 words
A method according to claim 2 wherein said nanocrystalline particles are present in pores in said glassy matrix.
Claim 5
Dependent Claim
14 words
A method according to claim 3 wherein said radiation comprises UV or ionizing radiation.
Claim 6
Dependent Claim
26 words
A method according to claim 4 wherein said radiation is selected from the group consisting essentially of UV, α, β, γ and X-radiation and neutron radiation.
Claim 7
Dependent Claim
19 words
A method according to claim 5 wherein said glassy matrix is partially consolidated to seal said nanocrystalline particles within.
Claim 8
Dependent Claim
25 words
A method according to claim 6 wherein said phosphor comprises Group II A , II B , VI A , VI B and II-VI semiconductors.
Claim 9
Dependent Claim
104 words
A method according to claim 6 wherein said phosphor is selected from the group consisting essentially of ZnS, doped with at least one activating metal ions of Cu, Mn, Ag, Pb and Eu, LiF doped with at least one activating metal ions of Ti, Mg, Cu and P, Li 2 B 4 O 7 :Mn, SrS, BaS, GaS, CaF 2 doped with Mg or rare earth metal ions, alkali metal sulfates doped with at least one of Cu, Dy or Th ions, MgS doped with one or both of Eu and Sm activating metal ions, and alkali metal halides doped with lanthanide metal ions.
Claim 10
Dependent Claim
13 words
A method according to claim 8 wherein said radiation consists of UV radiation.
Claim 11
Independent Claim
93 words
A method for detecting radiation and determining absorbed dosage using a thermoluminescent dosimeter which comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix, said method comprising the steps of: (i) exposing said dosimeter to a radiation containing environment for a predetermined period of time; (ii) removing the irradiated dosimeter from said environment; (iii) heating said irradiated dosimeter to produce a thermoluminescent glow curve; (iv) recording said glow curve and comparing it with glow curves obtained from a known radiation dose, and (v) determining the radiation dosage experienced by said dosimeter.
Claim 12
Independent Claim
93 words
A method for detecting radiation and determining absorbed dosage using a thermoluminescent dosimeter which comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix, said method comprising the steps of: (i) exposing said dosimeter to a radiation containing environment for a predetermined period of time; (ii) removing the irradiated dosimeter from said environment; (iii) heating said irradiated dosimeter to produce a thermoluminescent glow curve; (iv) recording said glow curve and comparing it with glow curves obtained from a known radiation dose, and (v) determining the radiation dosage experienced by said dosimeter.
Claim 13
Dependent Claim
34 words
A method according to claim 10 wherein said phosphor comprises a phosphor which, when heated after being exposed to ionizing radiation, emits thermoluminescent light, the intensity of which is indicative of the absorbed dose.
Claim 14
Dependent Claim
18 words
A method according to claim 11 wherein said nanocrystalline particles are present in pores in said glassy matrix.
Claim 15
Dependent Claim
14 words
A method according to claim 12 wherein said radiation comprises UV or ionizing radiation.
Claim 16
Dependent Claim
26 words
A method according to claim 13 wherein said radiation is selected from the group consisting essentially of UV, α, β, γ and X-radiation and neutron radiation.
Claim 17
Dependent Claim
19 words
A method according to claim 14 wherein said glassy matrix is partially consolidated to seal said nanocrystalline particles within.
Claim 18
Dependent Claim
25 words
A method according to claim 15 wherein said phosphor comprises Group II A , II B , VI A , VI B and II-VI semiconductors.
Claim 19
Dependent Claim
104 words
A method according to claim 15 wherein said phosphor is selected from the group consisting essentially of ZnS, doped with at least one activating metal ions of Cu, Mn, Ag, Pb and Eu, LiF doped with at least one activating metal ions of Ti, Mg, Cu and P, Li 2 B 4 O 7 :Mn, SrS, BaS, CaS, CaF 2 doped with Mg or rare earth metal ions, alkali metal sulfates doped with at least one of Cu, Dy or Th ions, MgS doped with one or both of Eu and Sm activating metal ions, and alkali metal halides doped with lanthanide metal ions.
Claim 20
Dependent Claim
13 words
A method according to claim 17 wherein said radiation consists of UV radiation.
Claim 21
Independent Claim
115 words
A method for detecting radiation in an environment in which said radiation is present, said method comprising placing a thermoluminescent radiation dosimeter in said environment for a predetermined period of time, removing said irradiated dosimeter from said environment and then heating said irradiated dosimeter so that it emits thermoluminescent light of an intensity indicative of the absorbed dose and determining the absorbed dose from said emitted light, wherein said dosimeter is in the form of a flat plate with parallel faces and comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix, and wherein said emitted light is guided by total internal reflection to the edges of said dosimeter where it is detected.
Claim 22
Independent Claim
115 words
A method for detecting radiation in an environment in which said radiation is present, said method comprising placing a thermoluminescent radiation dosimeter in said environment for a predetermined period of time, removing said irradiated dosimeter from said environment and then heating said irradiated dosimeter so that it emits thermoluminescent light of an intensity indicative of the absorbed dose and determining the absorbed dose from said emitted light, wherein said dosimeter is in the form of a flat plate with parallel faces and comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix, and wherein said emitted light is guided by total internal reflection to the edges of said dosimeter where it is detected.
Claim 23
Dependent Claim
14 words
A method according to claim 19 wherein said radiation is α or β radiation.
Claim 24
Dependent Claim
45 words
A thermoluminescent dosimeter which comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix in the form of a flat plate with parallel faces, whereby thermoluminescent light emitted by said dosimeter is guided by total internal reflection to the edges of said dosimeter.
Claim 25
Dependent Claim
45 words
A thermoluminescent dosimeter which comprises nanocrystalline thermoluminescent phosphor particles dispersed throughout a light transparent, glassy matrix in the form of a flat plate with parallel faces, whereby thermoluminescent light emitted by said dosimeter is guided by total internal reflection to the edges of said dosimeter.
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