Scintillator and radiation dosimeter using same

Patent metadata

Field	Value
Publication number	US-10145963-B2
Application number	US-201615549591-A
Country	US
Kind code	B2
Filing date	Feb 10, 2016
Priority date	Feb 12, 2015
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

Provided are a scintillator with improved energy sensitivity dependence within the energy range of diagnostic X-rays, more specifically in the range of 40-150 kV, and a radiation dosimeter using same. Due to the scintillator comprising a photopolymer resin that contains a polymerizable monomer, a filler, and a photopolymerization initiator, energy sensitivity dependence within the range of 40-150 kV is improved. Furthermore, changes in relative sensitivity within this energy range can be reduced to 3% or less by containing an inorganic fluorescent substance such as Zn 2 SiO 4 .

First claim

The invention claimed is:

1. A scintillator for a radiation dosimeter, the scintillator comprising:
a photopolymer resin that contains a polymerizable monomer, a filler, and a photopolymerization initiator.

2. The scintillator for a radiation dosimeter according to claim 1 , wherein the photopolymer resin further contains an inorganic fluorescent substance.

3. The scintillator for a radiation dosimeter according to claim 2 , wherein the inorganic fluorescent substance has a relative sensitivity characteristic in an X-ray energy range of 40 kV to 150 kV which has a complementary relationship with a relative sensitivity characteristic of the photopolymer resin.

4. The scintillator for a radiation dosimeter according to claim 2 , wherein the inorganic fluorescent substance is Zn 2 SiO 4 .

5. The scintillator for a radiation dosimeter according to claim 4 , wherein a content of the inorganic fluorescent substance is 0.01% by weight to 1% by weight.

6. The scintillator for a radiation dosimeter according to claim 1 , wherein the polymerizable monomer contains polyfunctional methacrylate.

7. The scintillator for a radiation dosimeter according to claim 1 , wherein the photopolymerization initiator contains camphorquinone and amines.

8. The scintillator for a radiation dosimeter according to claim 1 , wherein the polymerizable monomer contains polyfunctional methacrylate, the photopolymerization initiator contains camphorquinone and amines, and the photopolymer resin contains an inorganic fluorescent substance, and the inorganic fluorescent substance has a relative sensitivity characteristic in an X-ray energy range of 40 kV to 150 kV which has a complementary relationship with a relative sensitivity characteristic of the photopolymer resin.

9. The scintillator for a radiation dosimeter according to claim 8 , wherein the inorganic fluorescent substance contains at least one of Zn 2 SiO 4 , BaAl 12 O 19 , or BaMgAl 14 O 23.

10. A radiation dosimeter comprising:
the scintillator according to claim 1 ;
a photoelectric converter that converts light from the scintillator into an electric signal;
a counter that counts the number of events whose intensity is equal to or greater than a predetermined threshold with respect to the output from the photoelectric converter; and
a calculating unit that converts a count value of the counter into a radiation dose and outputs the radiation dose.

Assignees

• Univ Hokkaido Nat Univ Corp

Inventors

• Ishikawa Masayori

Classifications

• C09K11/02

  Use of particular materials as binders, particle coatings or suspension media therefor · CPC title

• G01T1/023 Primary

  Scintillation dose-rate meters · CPC title

• C09K11/595

  with zinc or cadmium · CPC title

• C09K11/59

  containing silicon · CPC title

• C09K11/643

  with alkaline earth metals · CPC title