CN111624644A - Three-dimensional position sensitive detector and energy correction method thereof - Google Patents
Three-dimensional position sensitive detector and energy correction method thereof Download PDFInfo
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Abstract
The invention discloses an energy correction method of a three-dimensional position sensitive detector and a corresponding detector, wherein the method comprises the following steps: generating a three-dimensional energy correction table; the detector detects to obtain the three-dimensional position of the incident photon acting in the detection crystal of the detector and the energy detected by the detector after the action; searching the three-dimensional energy correction table according to the three-dimensional position to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position; and calculating to obtain the energy of the incident photon by using the three-dimensional energy correction parameter and the detected energy. The energy correction method and the corresponding detector can correct the response dependency relationship of an electronic system of the ray detector on the ray position and can also correct the ray position dependency relationship in the photon transportation process, so that the energy resolution capability of the three-dimensional position sensitive detector is effectively improved.
Description
Technical Field
The invention belongs to the technical field of radiation detection, and particularly relates to an energy correction method of a three-dimensional position sensitive detector and a corresponding three-dimensional position sensitive detector.
Background
The energy of the ray is one of the main detection contents of the ray detector, and the energy resolution is one of the main indexes for evaluating the ray detector. In medical physical imaging systems, energy resolution directly affects imaging quality and doctor's accuracy of disease diagnosis; in the application of the high-energy particle astronomical physics field, the energy resolution directly influences the cognition of scientific researchers on the particle, the physical process and the celestial body characteristic; in a security and emergency detection system, the energy resolution directly influences the judgment of security workers and the like on the type of a radiation source; in radiation spectroscopy applications, energy resolution directly affects the resolution and quantitative accuracy of the elements and material compositions of the relevant workers.
Currently, radiation detectors characterize the energy of an incident radiation by the magnitude of the peak amplitude of an electronic output signal or the magnitude of the amplitude of a window integrated signal. Considering the energy correction from the practical point of view, on the one hand, the peak amplitude of the output signal or the amplitude of the window integrated signal and the energy of the incident ray show a better linear relationship in a certain energy range or a certain energy section, so that in the energy section, the amplitude of the electronic output signal can be directly used for representing the ray energy, and in the actual working process of the ray detector, the incident ray and the detection crystal in the ray detector are acted to the output signal of the ray detector, and usually undergo photoelectric and electro-optical signal conversion for many times, as well as signal amplification and other complex signal processing procedures, the linear relationship is affected by a number of factors, therefore, the influence factors need to be considered as fully as possible and energy correction needs to be introduced after correction so as to improve the energy resolution of the ray detector. On the other hand, when the electronic output signal of the radiation detector is close to saturation, the linear relationship between the peak amplitude of the electronic output signal or the amplitude of the window integration signal and the energy of the incident radiation is not maintained any longer, but only a monotonic relationship is maintained, and then the amplitude of the electronic output signal needs to be corrected by a certain amplitude energy correction method so as to more accurately represent the energy of the radiation.
Currently, in the industry, the corresponding functional relationship between the amplitude of the electronic output signal and the incident ray energy is usually obtained through experiments, and is stored as an amplitude energy lookup table, and the ray energy is corrected through an online or offline energy correction algorithm. In addition, the mainstream ray energy correction method in the industry is to store a unique amplitude energy lookup table, and for rays acting at different positions in a ray detector, energy correction is carried out through the unique amplitude energy lookup table.
Compared with the prior art of ray detectors without energy correction, the method effectively improves the detection accuracy of ray energy, but the method does not consider the dependence of energy correction on the position (hereinafter referred to as ray position) of rays in the ray detector, so that the energy correction is not refined, and the energy measurement accuracy of the ray detector is reduced. In addition, the ray energy correction method does not consider that transmission processes, light losses, quantum efficiencies and the like related to different secondary visible light photons generated after incident rays act on different positions of the ray detector are different when the ray detector works, so that in actual work, even if the incident ray energy is the same, output signals generated on the detector have different amplitudes as long as the acting positions of the rays are different.
The ray detector is mainly a two-dimensional sensitive detector for plane imaging or detecting plane signals at present, and the leading edge technology is presented as a trend for developing the ray detector into a three-dimensional sensitive detector for three-dimensional imaging or detecting three-dimensional stereo objects. In the application of the three-dimensional sensitive detector, the dependence of the output signal of the three-dimensional sensitive detector on the position of the ray is more prominent. The traditional ray energy correction method is difficult to adapt to the requirement of a three-dimensional position sensitive detector on high energy resolution precision.
Disclosure of Invention
In order to solve the problems, the invention provides an energy correction method of a three-dimensional position sensitive detector and simultaneously provides a corresponding three-dimensional position sensitive detector.
The energy correction method of the three-dimensional position sensitive detector provided by the invention comprises the following steps:
generating a three-dimensional energy correction table of the three-dimensional position sensitive detector;
detecting by the three-dimensional position sensitive detector to obtain a three-dimensional position PA where the incident photon A acts in a detection crystal of the three-dimensional position sensitive detector, and obtaining energy EA detected by the three-dimensional position sensitive detector after the action;
searching the three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position PA;
and calculating to obtain the deposition energy E of the incident photon A by using the three-dimensional energy correction parameters and the energy EA obtained by detection, and further obtaining an incident photon energy spectrum measured by the detector.
Further, generating the three-dimensional energy correction table comprises the steps of:
s1, performing data processing on the structure of the detection crystal to obtain a data virtual three-dimensional structure of the detection crystal;
s2, processing the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, wherein the data virtual three-dimensional structure is composed of the N data virtual three-dimensional small units, and N is an integer greater than 1;
s3, irradiating the three-dimensional position sensitive detector by using an incident photon source, wherein the energy of each incident photon B emitted by the incident photon source is known;
s4, acquiring information of the respective actions of the incident photons B in the detection crystal through a data acquisition unit of the three-dimensional position sensitive detector to obtain respective three-dimensional positions PB of the respective actions, and obtaining energy EBP0 detected by the three-dimensional position sensitive detector corresponding to the incident photons B respectively after the respective actions are performed;
s5, according to the corresponding relation between each three-dimensional position PB and each data virtual three-dimensional small cell, corresponding each detected energy EBP0 to each data virtual three-dimensional small cell, and obtaining detected energy EBPs of each data virtual three-dimensional small cell, wherein the detected energy EBPs correspond to the energy of each incident photon B respectively;
s6, calculating and obtaining the correlation between the energy of each incident photon B and the corresponding energy EBP obtained by detection for each data virtual three-dimensional small unit;
and S7, completing the generation of the three-dimensional energy correction table.
Further, in the step S2, the size of the data virtual three-dimensional small unit in each direction of the three dimensions is not smaller than the positioning resolution of the three-dimensional position-sensitive detector in the corresponding direction, or the size of the data virtual three-dimensional small unit is taken as mm3And (4) stages.
Further, in the step S3, the number m of the types of energy of the incident photons B is an integer not less than 3, and the energy of the incident photons B is E1，E2，…，Em。
Further, in the step S3, the probe crystals corresponding to the data virtual three-dimensional cells are respectively provided with energy E1，E2，…，EmAnd the energy detected by the partial detection crystal is EiThe number of the incident photons B is not less than 1000, wherein i is not less than 1 and not more than m, and i is an integer.
Further, the energy detected by the part of the detection crystal is EiThe number of said incident photons B is not less than 10000.
Further, in the step S5, the energy EBP0 obtained by the detection in each of the data virtual three-dimensional small cells is counted to obtain the energy E of each incident photon B in each of the data virtual three-dimensional small cells1，E2，…，EmRespectively corresponding energy distribution spectrum, and energy value EP corresponding to main peak position of each energy distribution spectrum1，EP2，…，EPmFor the data, the energy E of each incident photon B in a virtual three-dimensional small unit1，E2，…，EmAnd respectively corresponding to the detected energy EBP.
Further, in the step S6, for each of the data virtual three-dimensional cells, the energy E of each incident photon B is calculated by a nonlinear least squares fitting method1，E2，…，EmWith corresponding detected energy EP1，EP2，…，EPmThe correlation of (2).
Further, the correlation satisfies the following equation:
and the alpha, the beta and the gamma are fitting parameters of the nonlinear least square fitting method, and each data virtual three-dimensional small unit has a set of corresponding correlation relation parameters.
Further, in the step S7, the position information of each data virtual three-dimensional small cell and the corresponding values of the fitting parameters α, β, and γ are stored in a data processing unit of the three-dimensional position-sensitive detector in a matrix form, so as to complete the generation of the three-dimensional energy correction table.
Further, when the deposition energy E of the incident photon a is calculated, the deposition energy E and the detected energy EA satisfy the following formula:
wherein, αA、βAAnd gammaAAnd searching a three-dimensional energy correction parameter obtained by the three-dimensional energy correction table according to the three-dimensional position PA.
The present invention also provides a three-dimensional position sensitive detector, comprising:
a detection crystal, a data acquisition unit and a data processing unit,
the detection crystal is used for detecting incident photons A and reacting with the incident photons A after the three-dimensional position sensitive detector is irradiated by the incident photons A;
the data acquisition unit is used for acquiring information of the action of the incident photon A in the detection crystal, acquiring a three-dimensional position PA of the action and energy EA obtained by the detection of the three-dimensional position sensitive detector after the action, and transmitting the three-dimensional position PA and the energy EA obtained by the detection to the data processing unit;
the data processing unit is used for searching a three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position PA, calculating and obtaining the deposition energy E of the incident photon A by using the three-dimensional energy correction parameter and the energy EA obtained by detection, and further obtaining an incident photon energy spectrum.
Furthermore, the detection crystal is also used for detecting and collecting all the light emitted by the incident photon source to the three-dimensional position sensitive detector when the three-dimensional energy correction table is generatedIncident photons B, wherein the number m of the energy types of each incident photon B is an integer not less than 3, and the energy of each incident photon B is E1，E2，…，Em；
The data acquisition unit is further used for acquiring information of the respective actions of the incident photons B in the detection crystal to obtain three-dimensional positions PB of the respective actions and energy EBP0 detected by the three-dimensional position sensitive detectors respectively corresponding to the incident photons B after the respective actions;
the data acquisition unit is further configured to perform data processing on the structure of the detection crystal to obtain a data virtual three-dimensional structure of the detection crystal, and process the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, where the N data virtual three-dimensional small units form the data virtual three-dimensional structure, and the data acquisition unit is further configured to transmit information of the three-dimensional position PB, the detected energy EBP0, and each data virtual three-dimensional small unit to the data processing unit, where N is an integer greater than 1;
the data processing unit is configured to correspond the detected energy EBP0 to the data virtual three-dimensional cells according to a corresponding relationship between the three-dimensional positions PB and the data virtual three-dimensional cells, to obtain detected energy EBPs of the data virtual three-dimensional cells, which correspond to the energies of the incident photons B, respectively, and calculate a correlation between the energies of the incident photons B and the detected energy EBP corresponding to each data virtual three-dimensional cell, to complete generation of the three-dimensional energy correction table,
wherein, when the incident photon source is used for irradiating the three-dimensional position sensitive detector, the part of the detection crystal corresponding to each data virtual three-dimensional small unit is respectively provided with energy E1，E2，…，EmAnd said each incident photon B impinges and said portion of the detector crystal records an energy Ei(i is more than or equal to 1 and less than or equal to m, i is an integer) is not less than 1000。
Further, the partially probed crystal records an energy Ei(i is more than or equal to 1 and less than or equal to m, and i is an integer) is not less than 10000.
Further, the data acquisition unit is used for processing the data virtual three-dimensional structure to obtain the data virtual three-dimensional small unit with the size in each three-dimensional direction not smaller than the positioning resolution of the three-dimensional position sensitive detector in the corresponding direction, or obtain the data virtual three-dimensional small unit with the three-dimensional size being mm3The data of a stage is a virtual three-dimensional cell.
Further, the data processing unit is configured to count the energy EBP0 obtained by each detection in each data virtual three-dimensional small cell to obtain the energy E of each incident photon B in each data virtual three-dimensional small cell1，E2，…，EmRespectively corresponding energy distribution spectrum, and energy value EP corresponding to main peak position of each energy distribution spectrum1，EP2，…，EPmFor the data, the energy E of each incident photon B in a virtual three-dimensional small unit1，E2，…，EmAnd respectively corresponding to the detected energy EBP.
Further, the data processing unit is used for calculating the energy E of each incident photon B in each data virtual three-dimensional small unit by adopting a nonlinear least square fitting method1，E2，…，EmWith corresponding detected energy EP1，EP2，…，EPmThe correlation of (2).
Further, the correlation satisfies:
wherein, α, β, γ in the formula are fitting parameters of the nonlinear least square fitting method, and each data virtual three-dimensional small unit has a set of corresponding correlation parameters.
Further, the data processing unit is used for storing the position information of each data virtual three-dimensional small unit and the corresponding values of the fitting parameters alpha, beta and gamma in a matrix form so as to complete the generation of the three-dimensional energy correction table.
Further, the data processing unit is configured to, according to the correlation between the deposition energy E and the detected energy EA:
to calculate the deposition energy E of the incident photon a,
wherein, α in the formulaA、βAAnd gammaAAnd searching the three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter.
The energy correction method of the three-dimensional position sensitive detector and the corresponding three-dimensional position sensitive detector not only can correct the response dependency relationship of an electronic system of the ray detector on the ray position, but also can correct the ray position dependency relationship in the photon transportation process, thereby effectively improving the energy resolution capability of the three-dimensional position sensitive detector. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 shows a schematic diagram of an energy correction method of a three-dimensional position-sensitive detector according to an embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention discloses an energy correction method of a three-dimensional position sensitive detector, wherein the three-dimensional position sensitive detector comprises a detection crystal. After the incident photons A are irradiated and react with the detection crystal, recording the energy detected by the three-dimensional position sensitive detector as the energy obtained by detection, wherein the energy correction method comprises the following basic steps:
generating a three-dimensional energy correction table of the three-dimensional position sensitive detector;
detecting by the three-dimensional position sensitive detector to obtain a three-dimensional position PA where the incident photon A acts in the detection crystal and energy EA obtained by detection, such as scintillation pulse energy;
searching the three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position PA;
and calculating the energy of the incident photon A by using the three-dimensional energy correction parameters and the energy EA obtained by detection, and further obtaining the energy spectrum of the incident photon A through counting statistics.
Wherein generating the three-dimensional energy correction table comprises the following basic steps:
emitting a number of incident photons B from an incident photon source to sufficiently illuminate portions of the detection crystal;
acquiring information of the action of each incident photon B in the detection crystal through a data acquisition unit of the three-dimensional position sensitive detector to obtain each three-dimensional position PB of each incident photon B in the detection crystal and corresponding energy EBP obtained by detection, such as scintillation pulse energy;
performing data processing on the structure of the detection crystal to obtain a data virtual three-dimensional structure of the detection crystal;
processing the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, wherein the data virtual three-dimensional structure is composed of the N data virtual three-dimensional small units, and N is an integer greater than 1;
acquiring the energy EBP obtained by detection corresponding to the energy of each incident photon B of each data virtual three-dimensional small unit according to the corresponding relation between the acquired three-dimensional positions PB and the positions of the data virtual three-dimensional small units;
and calculating and obtaining parameters of correlation relations between various energies of the incident photons B corresponding to the data virtual three-dimensional small units and the corresponding detected energy EBP.
The energy correction method of the three-dimensional position sensitive gamma detector of the present invention is further disclosed below by taking a three-dimensional position sensitive gamma detector for imaging detection of a gamma source as an example. The working principle of the active part or the detection part (i.e. the detection crystal) of the three-dimensional position sensitive gamma detector can be briefly described as follows: gamma photons with certain energy emitted by an external gamma source are incident into the three-dimensional position-sensitive gamma detector, the incident gamma photons react with a scintillation crystal (or a scintillation crystal array) after entering the detection crystal, and energy is deposited to generate scintillation photons, and the scintillation photons are transported in the scintillation crystal and then detected by a photoelectric conversion device at the end of the scintillation crystal. According to the principle, each gamma photon is incident to the scintillation crystal to act and deposit energy, and the number of the generated scintillation photons is in direct proportion to the deposited energy; the photoelectric conversion device detects the scintillation photons and generates scintillation pulse signals, the amplitude or the integral area of the scintillation pulse signals is generally used as the energy of scintillation pulses, if a certain number of gamma photon events are collected, a plurality of scintillation pulse signals can be obtained, and then a scintillation pulse energy distribution spectrum related to the gamma photon energy can be obtained. The scintillation pulse energy distribution spectrum depends on the location where the incident gamma photon acts in the scintillation crystal, and differs from location to location where the action occurs.
In the energy correction method of the three-dimensional position sensitive gamma detector, firstly, according to the formation principle of the scintillation pulse energy distribution spectrum, a three-dimensional energy correction table of the three-dimensional position sensitive gamma detector is generated by the following method:
the scintillation crystal is sufficiently irradiated by a certain number of incident gamma photons B through an external gamma source, wherein the energy of each incident gamma photon B is known, the number m of the energy types of each incident gamma photon B is more than or equal to 3, m is an integer, and the energy of each incident gamma photon B is E1，E2，…，EmIn actual practice, several sources, Tc-99m (emission gamma energy 140keV), I-131 (primary gamma photon energy 364keV), Cs-137 (primary gamma photon energy 662keV), Na-22 (primary gamma photon energy 511keV and 1275keV), respectively, are used to sequentially perform experiments to provide incident gamma photons B with different energies;
performing data processing on the structure of the scintillation crystal to obtain a data virtual three-dimensional structure of the scintillation crystal;
processing the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, wherein the data virtual three-dimensional structure is composed of the N data virtual three-dimensional small units, N is an integer larger than 1, the size of each data virtual three-dimensional small unit in each three-dimensional direction is not smaller than the resolution of the three-dimensional position sensitive gamma detector in the corresponding direction, and in actual work, the size of each data virtual three-dimensional small unit can be mm3The grade is 4mm × 4mm × 4mm, in order to meet the above requirement of sufficient irradiation of each part of the scintillation crystal, each part of the scintillation crystal corresponding to each data virtual three-dimensional small unit receives the input comprising all m energy typesGamma photons are emitted, the number of the incident gamma photons B of each energy type is not less than 10000, for example, when the size of the data virtual three-dimensional small unit is 4mm × mm × mm, the part of the scintillation crystal corresponding to each data virtual three-dimensional small unit receives energy respectively as E1，E2，…，EmAnd the recorded or detected energy is Ei(1. ltoreq. i. ltoreq. m, i being an integer) of the number of incident gamma photons B preferably being not less than 10000;
acquiring information of the respective actions of the incident gamma photons B in the detection crystal through a data acquisition unit of the three-dimensional position sensitive gamma detector to obtain three-dimensional positions PB of the respective actions and energy EBP0 detected by the three-dimensional position sensitive detector respectively corresponding to the incident gamma photons B after the respective actions;
according to the corresponding relation between each three-dimensional position PB and each data virtual three-dimensional small cell, corresponding each detected energy EBP0 to each data virtual three-dimensional small cell, then counting each detected energy EBP0 in each data virtual three-dimensional small cell to obtain the energy E of each incident photon B in each data virtual three-dimensional small cell1，E2，…，EmRespectively corresponding energy distribution spectrum, and energy value EP corresponding to main peak position of each energy distribution spectrum1，EP2，…，EPmFor the data, the energy E of each incident photon B in a virtual three-dimensional small unit1，E2，…，EmRespectively corresponding to the detected energy EBP;
for each data virtual three-dimensional small unit, calculating the parameter of the correlation relation between the energy of the incident gamma photon B and the scintillation pulse energy EBP according to a nonlinear least square fitting method, wherein EiAnd EPiIs characterized by the following correlation relationship:
according to the above formula and E corresponding to each data virtual three-dimensional small unit1，E2，…，EmAnd EP1，EP2，…，EPmI.e., the values of α, β and gamma, respectively corresponding to the virtual three-dimensional cells of each data are obtained by calculation, wherein E isiIn keV, scintillation pulse energy EPiThe dimension of the sampled and digitized corresponding pulse signal amplitude or integral area is V or dimensionless, and α, γ are respectively the fitting parameters of the nonlinear least squares fitting method, i.e. the parameters of the correlation relationship, and each of the data virtual three-dimensional cells has a set of corresponding correlation relationship parameters.
Storing the position information of each data virtual three-dimensional small cell and the corresponding values of the fitting parameters α, β and gamma in a data processing unit of the three-dimensional position sensitive detector in a matrix form, namely, completing the generation of the three-dimensional energy correction table, wherein the values of the fitting parameters α, β and gamma stored in the data processing unit are the values of the three-dimensional energy correction parameters (the fitting parameters are the three-dimensional energy correction parameters), referring to fig. 1, wherein a three-dimensional position-dependent amplitude energy lookup table (hereinafter referred to as a lookup table) is the three-dimensional energy correction table, and the position (x) in the table is (x, the lookup table is simply referred to as a "three-dimensional energy correction table")o,yp,zq) For the three-dimensional position PB corresponding to each data virtual three-dimensional small cell, each data virtual three-dimensional small cell has respective values of α, β and γ in a one-to-one correspondence, where O is greater than or equal to 1 and less than or equal to O, P is greater than or equal to 1 and less than or equal to P, Q is greater than or equal to 1 and less than or equal to Q, O, P, Q respectively are the number of the data virtual three-dimensional small cells in each three-dimensional direction of the data virtual three-dimensional structure and O × P × Q is N, where N is the number of the data virtual three-dimensional small cells.
Referring to fig. 1, the energy correction method of the three-dimensional position sensitive gamma detector of the present invention includes the steps of, based on the three-dimensional energy correction table generated by the above method:
irradiating the three-dimensional position sensitive gamma detector by utilizing gamma photons A emitted by an external gamma source;
detecting by the three-dimensional position sensitive gamma detector to obtain a three-dimensional position PA (i.e., (x, y, z) in fig. 1) where the incident gamma photon a acts in a scintillation crystal of the three-dimensional position sensitive gamma detector and energy EA detected by the three-dimensional position sensitive gamma detector after the action occurs in fig. 1;
looking up the lookup table according to the three-dimensional position (x, y, z) to obtain a corresponding three-dimensional energy correction parameter αA、βAAnd gammaAWhen (X, y, z) is at position (X)1，YP，ZQ) When the data of (a) is virtual in a three-dimensional cell, then the three-dimensional energy correction parameters αA、βAAnd gammaATakes the value of (X) as the position1，YP，ZQ) The values of the energy correction parameters α, β and gamma in the amplitude energy lookup table corresponding to the virtual three-dimensional cells of (a);
and implementing an energy correction process by using the searched three-dimensional energy correction parameter and the detected energy EA through the correlation relationship, namely obtaining the deposition energy E of the incident photon A detected by the three-dimensional position sensitive gamma detector through the following calculation:
it should be noted that the incident photon with energy E is not necessarily deposited with all energy after being incident on the detector, and some incident photons may be scattered, so that part of the energy of the scattered photons is dissipated and not deposited, so that the deposited energy of the incident photons after being acted on the detection crystal such as the scintillation crystal may be smaller than E, but part of the photons may deposit all energy thereof, thereby forming a main peak on the energy spectrum as a basis for determining the energy of the incident photon a. We use the generated energy correction table to generate the actual deposition energy for each incident photon, which ultimately results in an energy spectrum.
The present invention also provides a three-dimensional position sensitive detector, preferably a three-dimensional position sensitive gamma detector, comprising: the detection crystal is a scintillation crystal, a data acquisition unit and a data processing unit.
In the generation of the three-dimensional energy correction table,
the scintillation crystal is used for detecting each incident gamma photon B emitted by irradiating the three-dimensional position sensitive gamma detector by an external gamma source, wherein the number m of energy types of each incident gamma photon B is not less than 3, and the energy of each incident gamma photon B is E1，E2，…，Em(ii) a In practice, at least three of Tc-99m (emission gamma energy 140keV), I-131 (primary gamma photon energy 364keV), Cs-137 (primary gamma photon energy 662keV), Na-22 (primary gamma photon energy 511keV and 1275keV) radiation sources, respectively, are sequentially used as external gamma sources to provide incident gamma photons B having different energies.
The data acquisition unit is used for acquiring information of the action of each incident gamma photon B in the scintillation crystal to obtain each three-dimensional position PB of the action and energy EBP0 detected by the three-dimensional position sensitive detector after the action, wherein the data acquisition unit comprises a photoelectric conversion device at the end part of the scintillation crystal, the photoelectric conversion device is used for detecting and receiving the scintillation photons generated after the action of each incident gamma photon B in the scintillation crystal, and then completing photoelectric conversion, generating and outputting scintillation pulse signals; the data acquisition unit is further configured to complete Analog-to-Digital (AD) conversion of each scintillation pulse signal and calculation of each three-dimensional position PB, and add energy of each type of scintillation pulse signal (corresponding to different energy types of incident gamma photon B) acquired in each detection in a similar manner, as energy of each scintillation pulse acquired in the detection, that is, energy EBP0 acquired by the three-dimensional position sensitive detector;
in addition, the data acquisition unit is further configured to: performing data processing on the structure of the scintillation crystal to obtain a data virtual three-dimensional structure of the scintillation crystal, and processing the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, wherein the data virtual three-dimensional structure is formed by the N data virtual three-dimensional small units, and N is an integer greater than 1; sending the three-dimensional positions PB, the scintillation pulse energies and the related information of the data virtual three-dimensional small units to the data processing unit;
the data processing unit is used for acquiring the energy E of each data virtual three-dimensional small unit corresponding to each incident gamma photon B according to the corresponding relation between each three-dimensional position PB and each data virtual three-dimensional small unit position1，E2，…，EmDetected energy EP of1，EP2，…，EPmAnd then, the following steps including a nonlinear least square fitting method and the like are carried out to generate the three-dimensional energy correction table.
When energy correction is carried out, the scintillation crystal is used for detecting incident gamma photon A after the three-dimensional position sensitive gamma detector is irradiated by the incident gamma photon A and reacting with the incident gamma photon A;
the data acquisition unit is used for acquiring information of the action of the incident gamma photon A in the scintillation crystal, acquiring a three-dimensional position PA where the action occurs and energy EA obtained by detection of the three-dimensional position sensitive gamma detector after the action occurs, and transmitting the acquired three-dimensional position PA and the energy EA obtained by detection to the data processing unit, wherein a photoelectric conversion device of the data acquisition unit is used for detecting and receiving each scintillation photon generated after the action of the incident gamma photon A in the scintillation crystal, then completing photoelectric conversion, and generating and outputting a corresponding scintillation pulse signal; the data acquisition unit is also used for finishing AD conversion of each scintillation pulse signal and calculation of the three-dimensional position PA. If a double-end read-out detector is adopted in the three-dimensional position sensitive detector, the energy of scintillation pulse signals output by the double ends and collected in the detection is taken as the scintillation pulse energy collected in the detection, namely the energy EA obtained by the detection, and if a single-end read-out detector is adopted in the three-dimensional position sensitive detector, the energy of each scintillation pulse signal collected in the detection is directly taken as the scintillation pulse energy collected in the detection, namely the energy EA obtained by the detection;
the data processing unit is used for searching a three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter α corresponding to the three-dimensional position PAA、βAAnd gammaAAnd implementing the energy correction process by using the searched three-dimensional energy correction parameter and the detected energy EA to calculate and obtain the energy of the incident gamma photon A.
The energy correction method of the three-dimensional position sensitive detector utilizes the positioning capacity of the three-dimensional position sensitive detector on the three-dimensional position acted by the incident ray in the detection crystal, and refines the detection crystal structure into a plurality of data virtual three-dimensional small units through data processing to generate a three-dimensional energy correction table, such as an amplitude energy lookup table, of the three-dimensional position corresponding to each data virtual three-dimensional small unit. The amplitude energy lookup tables of different three-dimensional positions are different from each other, and reflect the fine difference of the transmission process of the scintillation light caused by the action of incident photons such as gamma photons at different three-dimensional positions in the detection crystal. When the three-dimensional position sensitive detector is in operation, when incident photons such as gamma photons are detected, the three-dimensional position of the gamma photons acting in the three-dimensional position sensitive detector is calculated firstly, and then corresponding amplitude energy lookup table information is selected according to the three-dimensional position, so that the gamma photon energy of a gamma photon detection event is accurately corrected. The energy correction method of the invention not only can correct the response dependency relationship of an electronic system of the three-dimensional position sensitive detector on the three-dimensional position, but also can correct the dependency relationship of the scintillation photon transportation process and the three-dimensional position, and further can correct the nonlinearity of the correlation relationship between the scintillation pulse energy and the incident gamma photon energy when the gamma photon energy is increased, thereby effectively further improving the energy resolution capability of the three-dimensional position sensitive detector.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (20)
1. A method of energy correction for a three-dimensional position sensitive detector, the method comprising the steps of:
generating a three-dimensional energy correction table of the three-dimensional position sensitive detector;
detecting by the three-dimensional position sensitive detector to obtain a three-dimensional position PA where the incident photon A acts in a detection crystal of the three-dimensional position sensitive detector, and obtaining energy EA detected by the three-dimensional position sensitive detector after the action;
searching the three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position PA;
and calculating to obtain the deposition energy E of the incident photon A by using the three-dimensional energy correction parameters and the energy EA obtained by detection, and further obtaining an incident photon energy spectrum measured by the detector.
2. The energy correction method of a three-dimensional position sensitive detector according to claim 1, wherein generating the three-dimensional energy correction table comprises the steps of:
s1, performing data processing on the structure of the detection crystal to obtain a data virtual three-dimensional structure of the detection crystal;
s2, processing the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, wherein the data virtual three-dimensional structure is composed of the N data virtual three-dimensional small units, and N is an integer greater than 1;
s3, irradiating the three-dimensional position sensitive detector by using an incident photon source, wherein the energy of each incident photon B emitted by the incident photon source is known;
s4, acquiring information of the respective actions of the incident photons B in the detection crystal through a data acquisition unit of the three-dimensional position sensitive detector to obtain respective three-dimensional positions PB of the respective actions, and obtaining energy EBP0 detected by the three-dimensional position sensitive detector corresponding to the incident photons B respectively after the respective actions are performed;
s5, according to the corresponding relation between each three-dimensional position PB and each data virtual three-dimensional small cell, corresponding each detected energy EBP0 to each data virtual three-dimensional small cell, and obtaining detected energy EBPs of each data virtual three-dimensional small cell, wherein the detected energy EBPs correspond to the energy of each incident photon B respectively;
s6, calculating and obtaining the correlation between the energy of each incident photon B and the corresponding energy EBP obtained by detection for each data virtual three-dimensional small unit;
and S7, completing the generation of the three-dimensional energy correction table.
3. The method of claim 2, wherein in step S2, the size of the data virtual three-dimensional small unit in each direction of three dimensions is not less than the positioning resolution of the three-dimensional position sensitive detector in the corresponding direction, or the size of the data virtual three-dimensional small unit is taken as mm3And (4) stages.
4. The method for energy correction of a three-dimensional position-sensitive detector according to claim 2 or 3, wherein in the step S3, the number m of the kinds of the energy of each incident photon B is an integer not less than 3, and the energy of each incident photon B is E1，E2，…，Em。
5. The energy correction method of the three-dimensional position-sensitive detector of claim 4, wherein in the step S3, corresponding to each of the dataParts of the detection crystal of the virtual three-dimensional small unit are respectively provided with energy E1，E2，…，EmAnd the energy detected by the partial detection crystal is EiThe number of the incident photons B is not less than 1000, wherein i is not less than 1 and not more than m, and i is an integer.
6. The method of claim 5, wherein the energy detected by the partially-detected crystal is EiThe number of said incident photons B is not less than 10000.
7. The method as claimed in claim 5 or 6, wherein in step S5, the energy E of each incident photon B in each data virtual three-dimensional cell is obtained by counting the energy EBP0 obtained by each detection in each data virtual three-dimensional cell1，E2，…，EmRespectively corresponding energy distribution spectrum, and energy value EP corresponding to main peak position of each energy distribution spectrum1，EP2，…，EPmFor the data, the energy E of each incident photon B in a virtual three-dimensional small unit1，E2，…，EmAnd respectively corresponding to the detected energy EBP.
8. The method for energy correction of a three-dimensional position-sensitive detector of claim 7, wherein in step S6, for each of the data virtual three-dimensional cells, the energy E of each incident photon B is calculated by a nonlinear least squares fit1，E2，…，EmWith corresponding detected energy EP1，EP2，…，EPmThe correlation of (2).
9. The method of claim 8, wherein the correlation satisfies the following equation:
and the alpha, the beta and the gamma are fitting parameters of the nonlinear least square fitting method, and each data virtual three-dimensional small unit has a set of corresponding correlation relation parameters.
10. The energy correction method of the three-dimensional position-sensitive detector according to claim 9, wherein in the step S7, the position information of each data virtual three-dimensional small cell and the corresponding values of the fitting parameters α, β and γ are stored in a matrix form in the data processing unit of the three-dimensional position-sensitive detector to complete the generation of the three-dimensional energy correction table.
11. The method of claim 10, wherein the energy E and the EA satisfy the following equation when calculating the energy E for the incident photon A:
wherein, αA、βAAnd gammaAAnd searching a three-dimensional energy correction parameter obtained by the three-dimensional energy correction table according to the three-dimensional position PA.
12. A three-dimensional position sensitive probe, the probe comprising:
a detection crystal, a data acquisition unit and a data processing unit,
wherein the content of the first and second substances,
the detection crystal is used for detecting the incident photons A and reacting with the incident photons A after the three-dimensional position sensitive detector is irradiated by the incident photons A;
the data acquisition unit is used for acquiring information of the action of the incident photon A in the detection crystal, acquiring a three-dimensional position PA of the action and energy EA obtained by the detection of the three-dimensional position sensitive detector after the action, and transmitting the three-dimensional position PA and the energy EA obtained by the detection to the data processing unit;
the data processing unit is used for searching a three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter corresponding to the three-dimensional position PA, calculating and obtaining the deposition energy E of the incident photon A by using the three-dimensional energy correction parameter and the energy EA obtained by detection, and further obtaining an incident photon energy spectrum.
13. Three-dimensional position-sensitive detector according to claim 12,
the detection crystal is further configured to detect and collect each incident photon B emitted by an incident photon source irradiating the three-dimensional position sensitive detector when the three-dimensional energy correction table is generated, where m, the number of energy types of each incident photon B is an integer not less than 3, and the energy of each incident photon B is E1，E2，…，Em；
The data acquisition unit is further used for acquiring information of the respective actions of the incident photons B in the detection crystal to obtain three-dimensional positions PB of the respective actions and energy EBP0 detected by the three-dimensional position sensitive detectors respectively corresponding to the incident photons B after the respective actions;
the data acquisition unit is further configured to perform data processing on the structure of the detection crystal to obtain a data virtual three-dimensional structure of the detection crystal, and process the data virtual three-dimensional structure to obtain N data virtual three-dimensional small units, where the N data virtual three-dimensional small units form the data virtual three-dimensional structure, and the data acquisition unit is further configured to transmit information of the three-dimensional position PB, the detected energy EBP0, and each data virtual three-dimensional small unit to the data processing unit, where N is an integer greater than 1;
the data processing unit is configured to correspond the detected energy EBP0 to the data virtual three-dimensional cells according to a corresponding relationship between the three-dimensional positions PB and the data virtual three-dimensional cells, to obtain detected energy EBPs of the data virtual three-dimensional cells, which correspond to the energies of the incident photons B, respectively, and calculate a correlation between the energies of the incident photons B and the detected energy EBP corresponding to each data virtual three-dimensional cell, to complete generation of the three-dimensional energy correction table,
wherein, when the incident photon source is used for irradiating the three-dimensional position sensitive detector, the part of the detection crystal corresponding to each data virtual three-dimensional small unit is respectively provided with energy E1，E2，…，EmAnd said each incident photon B impinges and said portion of the detector crystal records an energy EiThe number of the incident photons B is not less than 1000, wherein i is not less than 1 and not more than m, and i is an integer.
14. The three-dimensional position sensitive detector of claim 13, wherein the partially detecting crystal records an energy of EiThe number of said incident photons B is not less than 10000.
15. Three-dimensional position-sensitive detector according to claim 13 or 14,
the data acquisition unit is used for processing the data virtual three-dimensional structure to obtain the data virtual three-dimensional small unit with the size in each three-dimensional direction not smaller than the positioning resolution of the three-dimensional position sensitive detector in the corresponding direction, or obtain the data virtual three-dimensional small unit with the three-dimensional size of mm3The data of a stage is a virtual three-dimensional cell.
16. The three-dimensional position sensitive detector of claim 15,
the data processing unit is used for detecting each probe in each data virtual three-dimensional small unitThe measured energy EBP0 is counted to obtain the energy E of each incident photon B in each data virtual three-dimensional small cell1，E2，…，EmRespectively corresponding energy distribution spectrum, and energy value EP corresponding to main peak position of each energy distribution spectrum1，EP2，…，EPmFor the data, the energy E of each incident photon B in a virtual three-dimensional small unit1，E2，…，EmAnd respectively corresponding to the detected energy EBP.
17. The three-dimensional position sensitive detector of claim 16,
the data processing unit is used for calculating the energy E of each incident photon B in each data virtual three-dimensional small unit by adopting a nonlinear least square fitting method1，E2，…，EmWith corresponding detected energy EP1，EP2，…，EPmThe correlation of (2).
18. The three-dimensional position sensitive detector of claim 17,
the correlation satisfies the following conditions:
wherein, α, β, γ in the formula are fitting parameters of the nonlinear least square fitting method, and each data virtual three-dimensional small unit has a set of corresponding correlation parameters.
19. The three-dimensional position sensitive detector of claim 18,
the data processing unit is used for storing the position information of each data virtual three-dimensional small unit and the corresponding values of the fitting parameters alpha, beta and gamma in a matrix form so as to finish the generation of the three-dimensional energy correction table.
20. The three-dimensional position sensitive detector of claim 19,
the data processing unit is used for processing the correlation between the deposition energy E and the detected energy EA according to the following steps:
to calculate the deposition energy E of the incident photon a,
wherein, α in the formulaA、βAAnd gammaAAnd searching the three-dimensional energy correction table according to the three-dimensional position PA to obtain a three-dimensional energy correction parameter.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112882085A (en) * | 2021-02-05 | 2021-06-01 | 明峰医疗***股份有限公司 | Temperature-adaptive PET detector energy correction method, system and computer-readable storage medium |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08285948A (en) * | 1995-04-17 | 1996-11-01 | Aloka Co Ltd | Radiation dosimeter |
| JPH11288022A (en) * | 1998-04-03 | 1999-10-19 | Nikon Corp | Finder device |
| US20080310598A1 (en) * | 2007-03-14 | 2008-12-18 | Tsinghua University | Method for calibrating dual-energy CT system and method of image reconstruction |
| CN104035122A (en) * | 2014-05-22 | 2014-09-10 | 沈阳东软医疗***有限公司 | Method and device for correcting energy value |
| CN104337531A (en) * | 2013-07-25 | 2015-02-11 | 苏州瑞派宁科技有限公司 | Online energy conforming method and system for full-digital PET system |
| CN105824817A (en) * | 2015-01-05 | 2016-08-03 | 苏州瑞派宁科技有限公司 | Flash pulse digitization method |
| US20170219498A1 (en) * | 2016-02-01 | 2017-08-03 | The University Of North Carolina At Chapel Hill | Optical geometry calibration devices, systems, and related methods for three dimensional x-ray imaging |
| CN108182266A (en) * | 2018-01-10 | 2018-06-19 | 中国科学技术大学 | A kind of method that crystal number is determined using look-up table based on FPGA |
| CN109685866A (en) * | 2018-12-25 | 2019-04-26 | 上海联影医疗科技有限公司 | Crystal positions look-up table construction method, device, computer equipment and storage medium |
| CN110211095A (en) * | 2019-05-06 | 2019-09-06 | 东软医疗***股份有限公司 | Energy diagram and crystal positions search table generating method, device, storage medium |
-
2020
- 2020-06-11 CN CN202010529530.0A patent/CN111624644A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08285948A (en) * | 1995-04-17 | 1996-11-01 | Aloka Co Ltd | Radiation dosimeter |
| JPH11288022A (en) * | 1998-04-03 | 1999-10-19 | Nikon Corp | Finder device |
| US20080310598A1 (en) * | 2007-03-14 | 2008-12-18 | Tsinghua University | Method for calibrating dual-energy CT system and method of image reconstruction |
| CN104337531A (en) * | 2013-07-25 | 2015-02-11 | 苏州瑞派宁科技有限公司 | Online energy conforming method and system for full-digital PET system |
| CN104035122A (en) * | 2014-05-22 | 2014-09-10 | 沈阳东软医疗***有限公司 | Method and device for correcting energy value |
| CN105824817A (en) * | 2015-01-05 | 2016-08-03 | 苏州瑞派宁科技有限公司 | Flash pulse digitization method |
| US20170219498A1 (en) * | 2016-02-01 | 2017-08-03 | The University Of North Carolina At Chapel Hill | Optical geometry calibration devices, systems, and related methods for three dimensional x-ray imaging |
| CN108182266A (en) * | 2018-01-10 | 2018-06-19 | 中国科学技术大学 | A kind of method that crystal number is determined using look-up table based on FPGA |
| CN109685866A (en) * | 2018-12-25 | 2019-04-26 | 上海联影医疗科技有限公司 | Crystal positions look-up table construction method, device, computer equipment and storage medium |
| CN110211095A (en) * | 2019-05-06 | 2019-09-06 | 东软医疗***股份有限公司 | Energy diagram and crystal positions search table generating method, device, storage medium |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112882085A (en) * | 2021-02-05 | 2021-06-01 | 明峰医疗***股份有限公司 | Temperature-adaptive PET detector energy correction method, system and computer-readable storage medium |
| CN112882085B (en) * | 2021-02-05 | 2022-11-15 | 明峰医疗***股份有限公司 | Temperature-adaptive PET detector energy correction method and system |
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