Photonic calorimeter and process for performing calorimetry

Patent metadata

Field	Value
Publication number	US-2019293809-A1
Application number	US-201916276939-A
Country	US
Kind code	A1
Filing date	Feb 15, 2019
Priority date	Mar 23, 2018
Publication date	Sep 26, 2019
Grant date	—

Abstract

A photonic calorimeter converts ionizing radiation dose to heat and includes: a radiation absorber, a temperature compensator disposed within the radiation absorber, a compensation waveguide, a compensation resonator, a compensation resonator, a thermal isolator on which the radiation absorber is disposed and that thermally isolates the radiation absorber from heat loss by thermal transfer due to physical contact by an object, and the temperature compensator changes the optical resonance of the compensation resonator in response to a change in temperature of the radiation absorber due to absorption of the ionizing radiation by the radiation absorber.

First claim

What is claimed is:

1 . A photonic calorimeter for converting ionizing radiation dose to heat, the photonic calorimeter comprising:
a radiation absorber comprising an outer surface and an interior material disposed in the interior material and bounded by the outer surface such that the radiation absorber:
receives ionizing radiation; and
converts the ionizing radiation into heat;
a temperature compensator disposed within the radiation absorber and comprising:
a compensation waveguide disposed in optical communication with a compensation resonator and that:
receives primary compensation input light;
communicates a resonant frequency based on the primary compensation input light to the compensation resonator;
receives secondary compensation output light from the compensation resonator; and
transmits primary compensation output light that is based on the secondary compensation output light; and

a compensation resonator disposed in optical communication with the compensation waveguide and that:
comprises an optical resonance;
receives, from the compensation waveguide, the resonant frequency corresponding to the optical resonance; and
produces the secondary compensation output light in response to receipt of the resonant frequency;

a thermal isolator on which the radiation absorber is disposed and that thermally isolates the radiation absorber from heat loss by thermal transfer due to physical contact by an object, and
the temperature compensator changes the optical resonance of the compensation resonator in response to a change in temperature of the radiation absorber due to absorption of the ionizing radiation by the radiation absorber.

2 . The photonic calorimeter of claim 1 , further comprising a substrate on which the thermal isolator is disposed,
wherein the thermal isolator is interposed between the substrate and the radiation absorber, and the radiation absorber is thermally isolated from the substrate by the thermal isolator.

3 . The photonic calorimeter of claim 1 , wherein the compensation resonator comprises an element from
group I of the periodic table (IUPAC group 11), group II of the periodic table (IUPAC group 12), group III of the periodic table (IUPAC group 13), group IV of the periodic table (IUPAC group 14), group V of the periodic table (IUPAC group 15), or group VI of the periodic table (IUPAC group 16) in an absence of a compound semiconductor comprising a group semiconductor.

4 . The photonic calorimeter of claim 1 , wherein the radiation absorber comprises graphite or water.

5 . A process for performing calorimetry with the photonic calorimeter of claim 17 , the process comprising:
receiving, by the compensation waveguide, primary compensation input light; producing, by the compensation waveguide, resonant frequency from the primary compensation input light; receiving, by the compensation resonator, the resonant frequency from the compensation waveguide; producing, by the compensation resonator, secondary compensation output light from the resonant frequency; receiving, by the compensation waveguide, the secondary compensation output light from the compensation resonator; producing, by the compensation waveguide, primary compensation output light from the secondary compensation output light; subjecting the radiation absorber to ionizing radiation; producing, by radiation absorber, heat from the ionizing radiation; communicating the heat to the compensation resonator; and changing the optical resonance of the compensation resonator in response to producing heat from the ionizing radiation by the radiation absorber to perform calorimetry.

6 . The process for performing dosimetry of claim 5 , further comprising:
determining a first calorimeter response based on the primary compensation output light prior to subjecting the radiation absorber to the ionizing radiation.

7 . The process for performing dosimetry of claim 6 , further comprising:
determining a second calorimeter response based on the primary compensation output light after subjecting the radiation absorber to the ionizing radiation.

8 . The process for performing dosimetry of claim 7 , further comprising:
determining an amount of the ionizing radiation absorbed by the radiation absorber from the first calorimeter response and the second calorimeter response.

9 . The process for performing dosimetry of claim 8 , wherein determining the amount of the ionizing radiation absorbed by the radiation absorber comprises:
performing an inverse Monte Carlo conversion from a temperature change of the radiation absorber due to absorption of the ionizing radiation; and determining an energy absorbed per unit mass of the radiation absorber from heating with the inverse Monte Carlo conversion.

10 . The process for performing dosimetry of claim 7 , wherein the first calorimeter response and the second calorimeter response differ in a resonance frequency, an amount of transmission, or a combination comprising at least one of the foregoing differences.

Assignees

• Government Of The Us Secretary Of Commerce

Inventors

• Tosh Ronald
• Ahmed Zeeshan
• Fitzgerald Ryan P
• Klimov Nikolai

Classifications

• G01T7/00

  Details of radiation-measuring instruments · CPC title

• G02B6/29323

  Coupling to or out of the diffractive element through the lateral surface of the light guide (evanescent grating couplers G02B6/29332) · CPC title

• G01T1/12 Primary

  Calorimetric dosimeters · CPC title

• G01T1/026 Primary

  Semiconductor dose-rate meters · CPC title

• G02B2006/12107

  Grating · CPC title