Linear-response nanocrystal scintillators and methods of using the same

• US 9,618,632 B2
• Filed: 03/14/2013
• Issued: 04/11/2017
• Est. Priority Date: 03/22/2012
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Duke University
• Inventors: Stanton, Ian N., Yoshizumi, Terry T., Therien, Michael J.
• Primary Examiner(s): Makiya, David J
• Assistant Examiner(s): Jo, Taeho
• Application Number:
  US14/387,103
• Publication Number:
  US 20150083923A1
• Time in Patent Office: 1,489 Days
• Field of Search: 250367
• CPC Class Codes: G01T 1/20 with scintillation detectors
• CPC Class Codes: G01T 1/20185 Coupling means between the photodiode and the scintillator, e.g. optical couplings using adhesives with wavelength-shifting fibres
• CPC Class Codes: G01T 1/20187 Position of the scintillator with respect to the photodiode, e.g. photodiode surrounding the crystal, the crystal surrounding the photodiode, shape or size of the scintillator
• CPC Class Codes: G01T 1/202 the detector being a crystal

Abstract

Systems and devices incorporating radiation detection, and techniques and materials for improved radiation detection are provided that involve a nano-scintillator exhibiting a linear luminescent emission response to stimulating electromagnetic radiation. The nano-scintillator can include at least one nanocrystal comprising a rare earth element, a lanthanide dopant, and a spectator dopant, wherein the nanocrystal exhibits a linear luminescent emission response to stimulating electromagnetic radiation of wavelengths less than 100 nm. As one example, the nanocrystal is [Y_2-x0₃; Eu_x, Li_y], where x is 0.05 to 0.1 and y is 0.1 to 0.16, and has an average nanoparticle size of 40 to 70 nm. These nanocrystals can be fabricated through a glycine combustion method.

Claims

1. A system comprising:

a nano-scintillator exhibiting a linear or near linear luminescent emission response to stimulating electromagnetic radiation of wavelengths less than 100 nm;

a light sensor configured to sense light emitted from the nano-scintillator; and

a processor comprising;

a data collection module configured to receive calibration data from the light sensor during a calibration mode, and generate a linear response equation from the calibration data; and

a dose or energy determination module configured to convert response information received from the light sensor during normal operation into radiation information using the linear response equation.

2. The system according to claim 1, wherein the nano-scintillator comprises at least one nanocrystal comprising a rare earth element, a lanthanide dopant, and a spectator dopant.

3. The system according to claim 2, wherein the lanthanide dopant percentage of the nano-scintillator is optimized for a highest scintillation to dose efficiency while maintaining a linear scintillation response to radiation dose or energy.

4. The system according to claim 2, wherein the spectator dopant percentage of the nano-scintillator is optimized for a highest scintillation to dose efficiency while maintaining a linear scintillation response to radiation dose or energy.

5. The system according to claim 1, wherein the calibration data comprise data received from exposure of the nano-scintillator material to a known radiation source with known energies during the calibration mode.

6. The system according to claim 5, wherein the known radiation source is between 0 and 100 MV, an x-ray source, and/or a gamma ray source.

7. The system according to claim 1, wherein the nano-scintillator has a linear scintillation response to radiation energy from about 17 kV to about 180 kV.

8. The system according to claim 1, wherein the nano-scintillator has a linear scintillation response to radiation energy from about 0.18 MV to about 50 MV.

9. The system according to claim 1, wherein the nanocrystal is [Y_2-xO₃;

Eu_x, Li_y], where x is 0.05 to 0.15 and y is 0.1 to 0.25, with an average nanoparticle size of 40 to 70 nm.

10. The system according to claim 1, wherein the processor is configured to calculate and output an average real-time dose, and total integrated dose for a duration of a period in time.

11. The system according to claim 1, further comprising a communication interface configured to transmit a signal from the processor.

12. The system according to claim 11, wherein the dose or energy determination module is further configured to output an alert from the communication interface in response to a determination that the radiation information exceeds a threshold.