# US 11,994,645 B2 · Apparatus, system and method regarding borehole muon detector for muon radiography and tomography

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,994,645 B2
- Document ID: US11994645B2
- Status: Granted
- Kind: B2
- Application number: 17/614,478
- Filed: 2020-05-26
- Published: 2022-07-21
- Granted: 2024-05-28
- Earliest claimed: 2019-05-27
- Assignees: Ideon Technologies Inc.
- Applicants: Ideon Technologies Inc.
- Inventors: Douglas William Schouten; Jacobus Van Nieuwkoop
- Web page: https://patentgrep.com/patent/US11994645B2

## CPC

- G01T 1/201: {using scintillating fibres}
- G01T 1/2018: {Scintillation-photodiode combinations}
- G01T 1/20184: {Detector read-out circuitry, e.g. for clearing of traps, compensating for traps or compensating for direct hits}
- G01T 1/20185: {Coupling means between the photodiode and the scintillator, e.g. optical couplings using adhesives with wavelength-shifting fibres}
- G01V 5/04: specially adapted for well-logging
- G01V 5/06: for detecting naturally radioactive minerals
- G01V 5/26: Passive interrogation, i.e. by measuring radiation emitted by objects or goods
- G01T: MEASUREMENT OF NUCLEAR OR X-RADIATION (radiation analysis of materials, mass spectrometry G01N23/00; tubes for determining the presence, intensity, density or energy of radiation or particles H01J47/00)
- G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02)

## Abstract

A borehole muon detector for detecting and characterizing a geographic region of interest is provided, the borehole muon detector comprising a housing and sensor, which is housed in the housing, the sensor including: a plurality of photodetector elements; at least one printed circuit board in electrical communication with the plurality of photodetectors and including an integrated electronic circuit for tracking time; a first helical bundle of scintillator fibers; an oppositely wound helical bundle of scintillator fibers, the oppositely wound helical bundle, the first helical bundle and the opposite helical bundle defining an outer cylinder, which includes a first end and a second end and a bore therebetween, each scintillator fiber of each bundle directly optically connected to a photodetector element at least at one end and indirectly optically connected to the photodetector element at no more than one end; and a plurality of scintillator bars, each comprising a first end, a second end and an optical fiber extending from the first end to the second end, the plurality of scintillator bars vertically disposed in the bore of the outer cylinder, each optical fiber of the scintillator bar optically directly connected to a photodetector element at least at one end and indirectly optically connected to the photodetector at no more than one end.

## Claims

### Claim 1

A borehole muon detector for detecting and characterizing a geographic region of interest, the borehole muon detector comprising:
a housing; and
a sensor, which is housed in the housing, the sensor including:
a plurality of photodetector elements;
at least one printed circuit board in an electrical communication with the plurality of photodetector elements and including an integrated electronic circuit for tracking time;
a first helical bundle of scintillator fibers;
an oppositely wound helical bundle of scintillator fibers, the oppositely wound helical bundle of scintillator fibers and the first helical bundle of scintillator fibers defining an outer cylinder, which includes a first end, a second end, and a bore therebetween, each scintillator fiber of the first helical bundle of scintillator fibers and the oppositely wound helical bundle of scintillator fibers directly optically connected to a photodetector element of the plurality of photodetector elements at least at one end and indirectly optically connected to the photodetector element of the plurality of photodetector elements at no more than one end; and
a plurality of scintillator bars, each scintillator bar of the plurality of scintillator bars comprising a first end, a second end, and an optical fiber extending from the first end to the second end, the plurality of scintillator bars vertically disposed in the bore of the outer cylinder, the optical fiber of each scintillator bar of the plurality of scintillator bars optically directly connected to a photodetector element of the plurality of photodetector elements at least at one end and indirectly optically connected to the photodetector element of the plurality of photodetector elements at no more than one end.

### Claim 2 (depends on 1)

The borehole muon detector of claim 1, wherein the first helical bundle of scintillator fibers comprises at least one winding.

### Claim 3 (depends on 1, 2)

The borehole muon detector of claim 1 or 2, wherein the optical fiber of each scintillator bar comprises a wave-length shifting optical fiber.

### Claim 4 (depends on 3)

The borehole muon detector of claim 3, wherein the plurality of scintillator bars define an inner cylinder having an inner bore therethrough.

### Claim 5 (depends on 4)

The borehole muon detector of claim 4, wherein each scintillator bar of the plurality of scintillator bars has a triangular cross section, which includes a base and two sides.

### Claim 6 (depends on 5)

The borehole muon detector of claim 5, wherein the plurality of scintillator bars includes a plurality of first scintillator bars and a plurality of second scintillator bars, and the triangular cross section of each scintillator bar of the plurality of first scintillator bars is larger than the triangular cross section of each scintillator bar of the plurality of second scintillator bars.

### Claim 7 (depends on 6)

The borehole muon detector of claim 6, wherein the plurality of first scintillator bars alternates with the plurality of second scintillator bars, and the base of each scintillator bar of the plurality of first scintillator bars faces the outer cylinder, and the base of each scintillator bar of the plurality of second scintillator bars faces the inner bore.

### Claim 8 (depends on 3, 4, 5, 6, 7)

The borehole muon detector of any one of claims 3 to 7, wherein the optical fiber of each scintillator bar of the plurality of scintillator bars includes a bore in which the wave-length shifting optical fiber is housed.

### Claim 9 (depends on 3, 4, 5, 6, 7, 8)

The borehole muon detector of any one of claims 3 to 8, wherein each scintillator fiber of the first helical bundle of scintillator fibers and the oppositely wound helical bundle of scintillator fibers is directly optically connected to a photodetector element of the plurality of photodetector elements at each end.

### Claim 10 (depends on 3, 4, 5, 6, 7, 8, 9)

The borehole muon detector of any one of claims 3 to 9, wherein the wave-length shifting optical fiber of each scintillator bar is directly optically connected to a photodetector element of the plurality of photodetector elements at each end of the plurality of scintillator bars.

### Claim 11

A borehole muon detector for detecting and characterizing a geographic region of interest, the borehole muon detector comprising:
a housing; and
a sensor, which is housed in the housing, the sensor including:
a plurality of first photodetector elements;
a plurality of second photodetector elements;
at least one first printed circuit board in an electrical communication with the plurality of first photodetector elements, the at least one first printed circuit board including an integrated electronic circuit for tracking time;
at least one second printed circuit board in an electrical communication with the plurality of second photodetector elements, the at least one second printed circuit board including an integrated electronic circuit for tracking time;
a helical bundle of scintillator fibers comprising n windings,
where n is greater than zero and is not an integer, each fiber of the helical bundle of scintillator fibers directly optically connected to a photodetector element from among the plurality of first photodetector elements and the plurality of second photodetector elements at each end, the helical bundle of scintillator fibers defining an outer cylinder, which includes a bore therethrough; and
a plurality of scintillator bars, each scintillator bar of the plurality of scintillator bars comprising a first end, a second end, and an optical fiber extending from the first end to the second end, the plurality of scintillator bars vertically disposed in the outer cylinder to define an inner cylinder having an inner bore therethrough, the optical fiber of each scintillator bar of the plurality of scintillator bars optically directly connected to a photodetector element from among the plurality of first photodetector elements and the plurality of second photodetector elements at least at one end and indirectly optically connected to the photodetector element from among the plurality of first photodetector elements and the plurality of second photodetector elements at no more than one end.

### Claim 12 (depends on 11)

The borehole muon detector of claim 11, wherein the optical fiber of each scintillator bar comprises a wave-shifting optical fiber.

### Claim 13 (depends on 11, 12)

The borehole muon detector of claim 11 or 12, wherein n is greater than one.

### Claim 14 (depends on 11, 12, 13)

The borehole muon detector of any one of claims 11 to 13, wherein each scintillator bar of the plurality of scintillator bars has a triangular cross section, which includes a base and two sides.

### Claim 15 (depends on 14)

The borehole muon detector of claim 14, wherein the plurality of scintillator bars includes a plurality of first scintillator bars and a plurality of second scintillator bars, and the triangular cross section of each scintillator bar of the plurality of first scintillator bars is larger than the triangular cross section of each scintillator bar of the plurality of second scintillator bars.

### Claim 16 (depends on 15)

The borehole muon detector of claim 15, wherein the plurality of first scintillator bars alternates with the plurality of second scintillator bars, and the base of each scintillator bar of the plurality of first scintillator bars faces the outer cylinder, and the base of each scintillator bar of the plurality of second scintillator bars faces the inner bore.

### Claim 17 (depends on 11, 12, 13, 14, 15, 16)

The borehole muon detector of any one of claims 11 to 16, further comprising an oppositely wound helical bundle of scintillator fibers.

### Claim 18

A borehole muon detector for detecting and characterizing a geographic region of interest, the borehole muon detector comprising:
a housing; and
a sensor, which is housed in the housing, the sensor including:
a plurality of photodetector elements;
a printed circuit board is an electrical communication with the plurality of photodetector elements;
a plurality of scintillator fibers, each scintillator fiber of the plurality of scintillator fibers including a first end and a second end, the first end and the second end of each scintillator fiber optically connected to a photodetector element of the plurality of photodetector elements, the plurality of scintillator fibers arranged as a helical bundle of scintillator fibers defining an outer cylinder, which includes a bore therethrough, the helical bundle of scintillator fibers comprising n windings, where n is greater than zero and is not an integer; and
a plurality of scintillator bars, each scintillator bar of the plurality of scintillator bars comprising a first end, a second end, and an optical fiber extending from the first end to the second end, the plurality of scintillator bars vertically disposed in the bore of the outer cylinder, the optical fiber of each scintillator bar of the plurality of scintillator bars optically directly connected to a photodetector element of the plurality of photodetector elements at least at one end and indirectly optically connected to the photodetector element of the plurality of photodetector elements at no more than one end.

### Claim 19 (depends on 18)

The borehole muon detector of claim 18, wherein one end of each optical fiber of each scintillator bar of the plurality of scintillator bars includes a reflective layer.

### Claim 20 (depends on 18)

The borehole muon detector of claim 18, wherein both ends of each scintillator bar of the plurality of scintillator bars are optically connected to a photodetector element of the plurality of photodetector elements.

### Claim 21

A method of detecting and characterizing a geographic region of interest, the method comprising:
inserting a muon detector into a borehole, the muon detector including a housing and a sensor, the sensor including:
at least one helical bundle of scintillator fibers to define a bore,
a plurality of scintillator bars disposed along a length of the bore,
a plurality of optical fibers, each optical fiber of the plurality of optical fibers extending along a length of a corresponding scintillator bar from among the plurality of scintillator bars,
a plurality of photodetector elements optically connected to the at least one helical bundle of scintillator fibers and to the plurality of optical fibers, and
a printed circuit board electrically connected to the plurality of photodetector elements; and
in response to a plurality of muons traversing the at least one helical bundle of scintillator fibers and the plurality of scintillator bars:
generating an optical signal from the at least one helical bundle of scintillator fibers and the plurality of scintillator bars that have been traversed by the plurality of muons;
detecting, by the plurality of photodetector elements, the optical signal from the at least one helical bundle of scintillator fibers and the plurality of scintillator bars that have been traversed by the plurality of muons;
receiving, at the printed circuit board, a plurality of electrical signals from the plurality of photodetector elements; and
processing the plurality of electrical signals with the printed circuit board to determine a location of the geographic region of interest.