Optically stimulated luminescence dosimeters: principles, phosphors and applications

Published On 2022/11/21

This review paper discusses the basics of the optically stimulated luminescence (OSL) phenomenon, phosphors for OSL, functional design of OSL phosphors, and application areas of the OSL phenomenon, such as radiation dose monitoring for individual and environmental, computed radiography for medical and dental diagnosis, dating, security, archaeological dating, and autoradiography for drug discovery. Finally, the future prospects of the OSL phenomenon as passive-type dosimeters are mentioned.

Published On

2022/11/21

Volume

62

Issue

1

Page

010505

Authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

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H-Index(all)

44

H-Index(since 2020)

19

I-10 Index(all)

0

I-10 Index(since 2020)

0

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0

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Research Interests

Odor sensor

Dosimeter

Thin films

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Other Articles from authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Alloys and Compounds

Radiophotoluminescence properties of Bi-doped NaCaBO3

Bi-doped NaCaBO3 exhibits radiophotoluminescence (RPL) properties, where the Bi2+ centre is formed through X-ray irradiation. As a result of RPL, a broad emission band appears around 800 nm in the photoluminescence (PL) spectrum, attributed to X-ray irradiation. The intensity of the PL signal is proportional to the irradiation dose, making it useful for measuring accumulated radiation dose. The sensitivity depends on the doping concentration of Bi, and the optimal concentration to maximize sensitivity is approximately 0.005%. With a laboratory-constructed reader system, the optimal sample enables measurement of X-ray dose as low as 25 mGy. Following irradiation, the Bi2+ signal slightly increases by about 13%, but it is significantly reduced to around 7% of the initial value after heat treatment at 500°C for 100 s. The formation and annihilation of the Bi2+ centre can be reproduced multiple times. Therefore …

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Kanazawa Institute of Technology

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Radio-photoluminescence Properties of Eu-doped CaBPO5

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Japanese Journal of Applied Physics

Radiophotoluminescence properties of Eu-doped Li2SrSiO4 for radiation detectors

To search for new radiophotoluminescence (RPL) materials, Eu-doped Li 2 SrSiO 4 was synthesized by the solid-state reaction and then studied its RPL properties for radiation detector applications. All the samples were identified to be Li 2 SrSiO 4 by X-ray diffraction. The as-prepared sample shows photoluminescence (PL) due to Eu 3+ while an additional PL band appears due to a formation of Eu 2+ after X-ray irradiation. This indicates that the Eu-doped Li 2 SrSiO 4 has RPL properties. The sensitivity of RPL (or PL intensity of Eu 2+) to X-ray dose is the highest when the Eu concentration is 0.1%, and the dynamic range is 5–10 000 mGy. In addition, the generated Eu 2+ is so stable that only 5% of the signal degrades over 20 min after irradiation. The RPL signal notably decreases to about 30% of the initial value by heating at 500 C for 100 s, and it is reproducible multiple times even after the heat treatment.

2023/12/20

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Materials Science: Materials in Electronics

ESR studies to elucidate the origin of the RPL emission of undoped-CaSO4

Recent research has shown that CaSO4, without any intentional addition of impurities, exhibits remarkable radiophotoluminescence (RPL) properties. However, the origin of the RPL in CaSO4 has yet to be fully understood. ESR measurements were carried out to identify the defect species responsible for RPL and elucidate the luminescence’s origin. ESR measurements on undoped-CaSO4 with different radiation sensitivities showed SO4−, SO2−+SO3−, PO42−, Si=O3 in P2O5–SiO2 (E’ center), Al2O3 hole center and Mn2+ defect species in CaSO4. This means that CaSO4 contains Al2O3, Mn2+, P, and Si as impurities, which are not intentionally added to CaSO4. As the results of this study, the different impurity states may influence the radiation sensitivity of the materials. It is suggested that the deliberate addition of P and Si elements, Al2O3 and Mn2+ could control the RPL properties.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Research Bulletin

X-ray induced reduction of Sm3+ into Sm2+ in Li2CaSiO4 and its potential for radiation measurement applications

In Sm3+-doped Li2CaSiO4, the Sm3+ ion is reduced to the Sm2+ state by X-ray irradiation. The valence change was confirmed by the difference in their photoluminescence spectra, measured before and after irradiation. Only luminescence peaks due to the 4f-4f transitions of Sm3+ are observed before the irradiation while an additional luminescence band is observed at 900 nm due to the 5d-4f transition of Sm2+. The reaction is that a fraction of X-ray generated electrons is captured by Sm3+ ions, which convert to the Sm2+ state. The generated Sm2+ state is fairly stable while it is effectively reversed back to the Sm3+ state by a heat treatment at an elevated temperature. A numerical approximation revealed the activation energy to be 0.40 and 0.52 eV. Even after the heat-treatment, the reduction of Sm3+ to Sm2+ is reproducible multiple times, which shows good potential for using radiation measurement applications.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Materials Science: Materials in Electronics

Radio-photoluminescence properties of Eu-doped SrAl2O4 ceramics and thermally assisted charge transfer process

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Recent advances in radiophotoluminescence materials for luminescence dosimetry

Radiophotoluminescence (RPL) is a phenomenon in which a luminescence centre is formed in a medium upon interaction with ionizing radiation. The RPL is observed by a conventional photoluminescence (PL) technique, and the PL intensity is proportional to the dose. With the latter feature, the RPL has found successful applications in personnel and environmental dosimetry. However, the conventional materials considered for radiation measurements may be limited to Ag-doped phosphate glass, LiF, and Al 2 O 3: C, Mg. The recent research works, however, have found a number of additional RPL materials for luminescence dosimetry. The aim of the present paper is to review the series of newly reported RPL materials and potential applications in dosimetry.

2022/11/22

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Optically stimulated luminescence dosimeters: principles, phosphors and applications

This review paper discusses the basics of the optically stimulated luminescence (OSL) phenomenon, phosphors for OSL, functional design of OSL phosphors, and application areas of the OSL phenomenon, such as radiation dose monitoring for individual and environmental, computed radiography for medical and dental diagnosis, dating, security, archaeological dating, and autoradiography for drug discovery. Finally, the future prospects of the OSL phenomenon as passive-type dosimeters are mentioned.

2022/11/21

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

IEEJ Transactions on Sensors and Micromachines

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Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor Ueno, Chiemi ; Hirasawa, Kazuki ; Takei, Yoshinori ; Nanto, Hidehito Abstract Publication: IEEJ Transactions on Sensors and Micromachines Pub Date: June 2022 DOI: 10.1541/ieejsmas.142.117 Bibcode: 2022IJTSM.142..117U No Sources Found © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors and Materials

Radiophotoluminescence Imaging Reader for Passive Dosimetry

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

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radiophotoluminescence (RPL)

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Phosphors for Radiation Detectors

Optically‐Stimulated Luminescent Dosimeters

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Physical Review Research

Catalog of gamma-ray glows during four winter seasons in Japan

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2021/11/15

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Letters

Radiation-induced reduction of Eu3+ doped in SrAl2O4

In this letter, we report radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4. The RPL is a phenomenon in which a new luminescence center is generated by ionizing radiation. The material was synthesized via the solid-state reaction. The synthesized sample shows photoluminescence (PL) due to the 4f-4f transition of Eu3+ and the 4f65d1 → 4f7 transition of Eu2+. After X-ray irradiation, the former emission intensity decreases while the latter one increases, and the extent of the change depends on the radiation dose. The change in the RPL is attributed to a reduction of Eu3+ by trapping an X-ray generated electron (Eu3+→Eu2+). In addition, a heat-treatment effectively reverses the above reaction by detrapping an electron from the Eu2+ center.

2021/11/15

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors & Materials

TSL/OSL/RPL Automated and Integrated Measurement System (TORAIMS).

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Hidehito Nanto

Kanazawa Institute of Technology

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

電気学会研究会資料

Transient response analysis and feature extraction of semiconductor gas sensors for an application to machine olfaction

瀬戸就一 他: 半導体式ガスセンサの過渡応答出力の解析, 電気学会論文誌 E センサマイクロマシン準部門誌 Vol. 125 No. 3, p. 129-134 (2005)