Detector device, dual energy CT system and detection method using the system

Patent metadata

Field	Value
Publication number	US-9885801-B2
Application number	US-201514748407-A
Country	US
Kind code	B2
Filing date	Jun 24, 2015
Priority date	Jun 25, 2014
Publication date	Feb 6, 2018
Grant date	Feb 6, 2018

Abstract

The present disclosure discloses a detector device comprising a plurality of detector assemblies. Each detector assembly comprises at least one detection crystal units having a first energy response and those having a second energy response, which are both arranged along a first direction at intervals, each detection crystal unit having a first/second energy response including at least one detection crystals having a first/second energy response arranged along a second direction. The at least one detection crystal units having a first energy response and the at least one detection crystal units having a second energy response are, at least partially, alternatively arranged along the first direction when viewed from an incidence direction of the X-ray. The present disclosure also discloses a dual energy CT system having the detector device and a CT detection method using this system.

First claim

What is claimed is:

1. A detector device for a dual energy CT system, wherein the dual energy CT system comprises a scanning tunnel through which an object to be scanned enters/exits the dual energy CT system along a transporting direction, an X-ray source provided at a side of the scanning tunnel, and a gantry provided at an opposite side of the scanning tunnel and on which the detector device is mounted, and wherein the detector device comprises a plurality of detector assemblies and a mounting plate, each detector assembly comprising:
at least two detection crystal units having a first energy response arranged along a first direction at intervals and arranged on a side of the mounting plate, and each detection crystal unit having the first energy response comprises at least one detection crystal having the first energy response arranged along the second direction, wherein the first direction is parallel to the transporting direction, and the second direction is perpendicular to the first direction in a plane of the mounting plate; and
at least one detection crystal unit having a second energy response arranged along the first direction at intervals and arranged on the other side of the mounting plate, and each detection crystal unit having the second energy response comprises at least one detection crystal having the second energy response arranged along the second direction, wherein the second energy is higher than the first energy;
wherein the number of the detection crystal units having the second energy response is less than that of the detection crystal units having the first energy response, and when viewed from an incidence direction of the X-ray, some of the at least two detection crystal units having the first energy response correspond to and are arranged to be aligned in a third direction perpendicular to the first direction and the second direction with respective detection crystal units of the at least one detection crystal unit having the second energy response.

2. The detector device for the dual energy CT system according to claim 1 , wherein the plurality of detector assemblies are arranged on a circular arc-shaped support centered at a center of the scanning tunnel or the X-ray source or on an approximate circular arc-shaped support consisting of a plurality of straight members.

3. The detector device for the dual energy CT system according to claim 2 , wherein the plurality of detector assemblies are arranged on the circular arc-shaped or approximate circular arc-shaped support in a spiral manner, so that a detection path for detecting the scanned object is a spiral path when the scanned object is transported to pass through a scanning plane.

4. The detector device for the dual energy CT system according to claim 1 , wherein incidence surfaces of the detection crystal units having the first energy response and/or the detection crystal units having the second energy response are provided thereon with filtering layers for adjusting the energy response of the detection crystal units.

5. The detector device for the dual energy CT system according to claim 1 , wherein the at least one detection crystal unit having the first energy response and the at least one detection crystal unit having the second energy response are mounted on different sides of different mounting plates.

6. The detector device for the dual energy CT system according to claim 1 , wherein the X-ray source is a single light source or a distributed multi-beam source.

7. A dual energy CT system, comprising:
a scanning tunnel through which an object to be scanned enters/exits the dual energy CT system along a transporting direction;
an X-ray source provided at a side of the scanning tunnel; and
the gantry provided at an opposite side of the scanning tunnel;
wherein the detector device according to claim 1 is mounted on the gantry.

8. The dual energy CT system according to claim 7 , further comprising:
an acquisition module for acquiring data signals from the plurality of detector assemblies; and
a control module for controlling radiation emission of the X-ray source and the data signal acquisition operation,
wherein the control module and the acquisition module are mounted within the same gantry.

9. The dual energy CT system according to claim 8 , further comprising a data processing module, and the data processing module is configured to perform a first data processing and a second data processing,
wherein in the first data processing, a single energy processing mode is used, and all the acquired data signals are used to reconstruct CT images of the scanned object; in the second data processing, a dual energy processing mode is used, and the acquired data signals are decomposed into data signals from the at least one detection crystal having a first energy response and data signals from the at least one detection crystal having a second energy response, and the decomposed data signals are used for reconstruction to obtain attenuation coefficient images, electron density images and atomic number images of the scanned article in X-ray scanning with different energies.

10. The dual energy CT system according to claim 9 , wherein the data processing module is configured to, in the second data processing, employ interpolation algorithms to obtain dual energy projection data which correspond to an alignment arrangement and then perform reconstruction of attenuation coefficient images, electron density images and atomic number images in X-ray scanning with different energies in the case where the detection crystal units having a second energy response and the detection crystal units having a first energy response are alternatively arranged.

Assignees

• Univ Tsinghua
• Nuctech Co Ltd

Inventors

• Chen Zhiqiang
• Zhang Li
• Jin Xin
• Huang Qingping
• Shen Le
• Sun Yunda

Classifications

• G01T1/202

  the detector being a crystal · CPC title

• G01N23/083 Primary

  the radiation being X-rays · CPC title

• A61B6/4266

  characterised by using a plurality of detector units (A61B6/4014 takes precedence) · CPC title

• G01T1/362

  with scintillation detectors · CPC title

• G01T7/08

  Means for conveying samples received · CPC title