System and method for equalizing pressure in ionization chamber of radiation device

Patent metadata

Field	Value
Publication number	US-11841104-B2
Application number	US-202016854821-A
Country	US
Kind code	B2
Filing date	Apr 21, 2020
Priority date	Apr 21, 2020
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A system for equalizing a pressure in an ionization chamber of a radiation device is provided. The system may include the ionization chamber including: a chamber housing including one or more chamber walls; a chamber volume inside the chamber housing, the chamber volume being filled with a radiation sensitive material; and a pressure adjustment apparatus operably coupled to the chamber volume via at least one wall of the one or more chamber walls, the pressure adjustment apparatus being configured to equalize a first pressure of the radiation sensitive material inside the chamber volume and a second pressure of ambient air outside the chamber housing.

First claim

What is claimed is:

1. A hybrid of a sealed and unsealed ionization chamber, comprising:
a chamber housing including one or more chamber walls, each of the one or more chamber walls having a thin thickness between 10 micrometers and 2 millimeters to facilitate detection of radiation beams by lowering an amount of attenuation experienced by the radiation beams due to transition through the one or more chamber walls;
a chamber volume inside the chamber housing, the chamber volume being filled with a radiation sensitive material and being on the path of the radiation beams;
one or more electrodes configured to establish an electric field in the chamber volume and measure a charge or current associated with the radiation sensitive material and produced, based on the electric field, in the chamber volume; and
a pressure adjustment apparatus operably coupled to the chamber volume via at least one wall of the one or more chamber walls, wherein the at least one wall includes a hole so that the chamber volume is in fluid communication with the pressure adjustment apparatus, the pressure adjustment apparatus being configured to equalize a first pressure of the radiation sensitive material inside the chamber volume relative to a second pressure of ambient air outside the chamber housing, the second pressure being influenced by at least one of temperature variation, pressure variation, or moisture variation in the ambient air, the pressure adjustment apparatus including a tube and an enclosure configured to function as a reservoir of the radiation sensitive material, wherein
the enclosure is connected to the chamber volume by the tube; and
the enclosure is configured to prevent the chamber volume from being in fluid communication with the ambient air and be nonpermeable for the radiation sensitive material and the ambient air.

2. The ionization chamber of claim 1 , wherein the chamber volume is airtight.

3. The ionization chamber of claim 1 , wherein the radiation sensitive material includes a gas.

4. The ionization chamber of claim 1 , wherein
the tube includes a first end and a second end, the first end being open to the chamber volume, and the second end being open to the enclosure; and
the tube has a varying size and/or shape along an axis of the tube.

5. The ionization chamber of claim 4 , wherein the at least one wall includes a hole, and the first end of the tube is airtightly connected to the at least one wall via the hole.

6. The ionization chamber of claim 4 , wherein the first end of the tube is directly connected to the at least one wall.

7. The ionization chamber of claim 4 , wherein the first end of the tube is connected to the at least one wall through a connecting piece.

8. The ionization chamber of claim 4 , wherein the enclosure is in fluid communication with the chamber volume through the tube.

9. The ionization chamber of claim 4 , wherein the enclosure and the tube are airtight such that the radiation sensitive material inside the enclosure and the tube is isolated from the ambient air.

10. The ionization chamber of claim 1 , wherein the enclosure is flexible.

11. The ionization chamber of claim 10 , wherein the enclosure includes a balloon, a bellows, or a flexible enclosure.

Assignees

• Shanghai United Imaging Healthcare Co Ltd

Inventors

• Maltz Jonathan
• Stahl Johannes

Classifications

• A61N5/1048

  Monitoring, verifying, controlling systems and methods · CPC title

• A61N5/103

  Treatment planning systems · CPC title

• A61B6/037

  Emission tomography · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title

• A61B6/02 Primary

  Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis · CPC title