CN112162310A - Method, system and computer device for depolarization of photon counting detector - Google Patents
Method, system and computer device for depolarization of photon counting detector Download PDFInfo
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Abstract
The application relates to a method, a system and a computer device for depolarization of a photon counting detector, wherein the method for depolarization of the photon counting detector comprises the following steps: the method comprises the steps of determining the illumination wavelength range of illumination equipment according to the defect energy level generated in the crystal growth process, and controlling the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range, so that the problem that the photon counting detector of the photon counting energy spectrum CT in the related technology is inaccurate in counting is solved, and the counting precision of the photon counting detector in the photon counting energy spectrum CT is improved.
Description
Technical Field
The present application relates to the field of medical devices, and in particular to methods, systems, and computer devices for depolarization of photon counting detectors.
Background
The Computerized Tomography (CT) technique uses precisely collimated X-ray beam, gamma ray, ultrasonic wave, etc. to scan the cross section of a human body one by one together with a detector with high sensitivity, has the characteristics of fast scanning time and clear image, etc., and can be used for the examination of various diseases.
In the related art, the core of the photon counting spectrum CT is a photon counting detector, which is to distinguish photons with different energies by adding a signal amplitude analyzing device in a special reading circuit of the detector to obtain photon counting in different energy intervals, most current photon counting detectors are made based on semiconductor materials, such as GaAs, CdTe, CdZnTe (CZT), and the like, but these semiconductor materials have growth defects during crystal growth, which cause polarization under the irradiation of X-rays, especially under high beam conditions, the interaction of the X-rays and photon counting detector materials (such as CdTe, CdZnTe (CZT)) generates electron-hole pairs, holes in the electron-hole pairs are captured by vacancies in the semiconductor materials during transport, the captured holes form space charge regions inside the semiconductor materials, and the space charge regions cause distortion of electric field emission inside the detector, and the electric field intensity can change with time, so that the response of the detector has instability with time, and the counting of the photon counting detector in the photon counting energy spectrum CT is inaccurate.
At present, no effective solution is provided aiming at the problem of inaccurate counting of a photon counting detector of photon counting energy spectrum CT in the related technology.
Disclosure of Invention
The embodiment of the application provides a depolarization method, a depolarization system and computer equipment of a photon counting detector, and aims to at least solve the problem of inaccurate counting of the photon counting detector of photon counting energy spectrum CT in the related art.
In a first aspect, an embodiment of the present application provides a method for depolarization of a photon counting detector, where the method includes:
determining the illumination wavelength range of illumination equipment according to the defect energy level generated in the crystal growth process;
and controlling the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range.
In some embodiments, the determining the illumination wavelength range of the illumination device according to the defect energy level generated in the crystal growth process comprises:
determining a photon energy range of the illumination device according to the defect energy level;
and determining the illumination wavelength range of the illumination equipment according to the photon energy range.
In some of these embodiments, the illumination wavelength range is 1000-1500nm in the case that the photon energy of the illumination device is not less than the defect energy level.
In some of these embodiments, in the case that the photon energy of the illumination device is not less than the defect energy level, the controlling the illumination device to illuminate the photon counting detector is:
periodically switching the illumination device on and off to illuminate the photon counting detector.
In some of these embodiments, said periodically switching said illumination device on and off to illuminate said photon counting detector comprises:
acquiring the trapping time of the holes and the de-trapping time of the holes;
and determining the illumination period of the illumination equipment according to the capture time and the de-capture time.
Switching the illumination device on and off according to the illumination period to illuminate the photon counting detector.
In some embodiments, the obtaining the trapping time for the hole to be trapped and obtaining the de-trapping time for the hole to be de-trapped includes:
irradiating the photon counting detector by using a preset illumination wavelength, and recording a first time set when the photon counting detector reaches polarization;
illuminating the photon technology detector by using a preset illumination wavelength, and recording a depolarization second time set of the photon counting detector;
an acquisition time and a de-acquisition time are determined based on the first time set and the second time set.
In some of these embodiments, in case of periodically switching on and off of the illumination device, the on time of the illumination device is less than or equal to 20ms and the off time of the illumination device is less than or equal to 20 ms.
In a second aspect, embodiments of the present application provide a system for depolarization of a photon counting detector, the system including a processor, a photon counting detector, and an illumination device;
the processor is used for determining the illumination wavelength range of the illumination equipment according to the defect energy level generated in the crystal growth process;
and the processor controls the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range.
In a third aspect, embodiments of the present application provide a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor implementing the method for depolarization of a photon counting detector according to the first aspect as described above when executing the computer program.
In a fourth aspect, the present application provides a storage medium, on which a computer program is stored, which when executed by a processor, implements the method for depolarization of a photon counting detector as described in the first aspect above.
Compared with the prior art, the method for depolarization of the photon counting detector provided by the embodiment of the application determines the illumination wavelength range of the illumination device according to the defect energy level generated in the crystal growth process, and controls the illumination device to illuminate the photon counting detector according to the illumination wavelength range, so that the problem that the photon counting detector of the photon counting energy spectrum CT in the prior art is inaccurate in counting is solved, and the counting precision of the photon counting detector in the photon counting energy spectrum CT is improved.
The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of the application.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
FIG. 1 is a schematic view of polarization inside a photon counting detector under high beam current conditions according to an embodiment of the present application;
FIG. 2 is a first flowchart of a method of photon counting detector depolarization according to an embodiment of the present application;
FIG. 3 is a flow chart two of a method of photon counting detector depolarization according to an embodiment of the present application;
fig. 4 is a schematic diagram of a positional relationship of an illumination device and a photon counting detector according to an embodiment of the present application;
FIG. 5 is a flow chart three of a method of photon counting detector depolarization according to an embodiment of the present application;
FIG. 6 is a flow chart diagram four of a method of photon counting detector depolarization in accordance with an embodiment of the present application;
FIG. 7 is a flow chart of a method of acquiring capture time and de-capture time according to an embodiment of the application;
FIG. 8 is a schematic diagram of a photon counting detector cathode plane electric field distribution according to an embodiment of the present application;
FIG. 9 is a block diagram of an apparatus for photon counting detector depolarization according to an embodiment of the present application;
FIG. 10 is a block diagram of a system for photon counting detector depolarization according to an embodiment of the present application;
fig. 11 is a schematic diagram of an internal structure of a computer device according to an embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided in the present application without any inventive step are within the scope of protection of the present application. Moreover, it should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another.
Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of ordinary skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments without conflict.
Unless defined otherwise, technical or scientific terms referred to herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar words throughout this application are not to be construed as limiting in number, and may refer to the singular or the plural. The present application is directed to the use of the terms "including," "comprising," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Reference herein to "a plurality" means greater than or equal to two. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.
The core of the photon counting spectrum CT is a photon counting detector, most of the current photon counting detectors are made based on semiconductor materials, such as CdTe, CdZnTe (CZT), etc., but these semiconductor materials all have polarization phenomenon at present, fig. 1 is a schematic polarization diagram inside the photon counting detector under high beam current condition according to the embodiment of the present application, as shown in fig. 1, during the operation of the photon counting spectrum CT, under the condition that the photon counting detector receives X-rays, holes generated by the X-rays in the photon counting detector can be captured by vacancies in the semiconductor material during the transportation process, the captured holes can form space charge regions inside the semiconductor material, the space charge regions can cause the emission distortion of the electric field inside the detector, and the electric field strength can change with time, thereby causing the response of the detector to have instability with the change with time, the method for depolarization of the CT detector is applied to photon counting spectrum CT, the photon counting detector is controlled to irradiate the photon counting detector under the condition that the photon counting detector receives rays, and the illumination wavelength range of the illumination device is determined according to the defect energy level generated in the crystal growth process.
The present embodiment provides a method for depolarization of a photon counting detector, and fig. 2 is a flowchart one of a method for depolarization of a photon counting detector according to an embodiment of the present application, as shown in fig. 2, the method includes the following steps:
step S201, determining the illumination wavelength range of illumination equipment according to the defect energy level generated in the crystal growth process;
it should be noted that the cause of the polarization effect of the CdTe, CZT, etc. semiconductor material is caused by growth defects in the crystal growth process, that is, there is a defect level in the crystal due to the growth defects, for example, the defect level generated by Gd vacancy in the semiconductor forbidden band is the main cause of the polarization phenomenon of the CdTe, CZT detector, in the case that the photon counting detector receives X-ray, the interaction of the X-ray and the photon counting detector material generates electron-hole pairs, and the holes in the electron-hole pairs are captured by Gd vacancies in the transportation process; it is further noted that ideally the semiconductor is of valence and conduction bands only, and that when doped with impurities or defects other energy levels are introduced between the conduction and valence bands, called defect levels.
Step S202, controlling the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range, wherein holes captured by the empty bits in the photon counting detector can be captured in the illumination wavelength range;
for example, in the case that holes are trapped by vacancies, the photon counting detector is illuminated by the illumination device, and the holes trapped by the vacancies are released from being trapped, so as to achieve the effect of eliminating the polarization effect.
Through the steps S201 to S202, since the defect level generated by the vacancy in the semiconductor forbidden band is the main cause of the polarization phenomenon of the CdTe and CZT detectors, that is, under the condition that the photon counting detector receives the X-ray, the interaction between the X-ray and the photon counting detector material generates an electron-hole pair, and the hole in the electron-hole pair is captured by the vacancy in the transportation process, under the condition that the photon counting detector receives the X-ray, the illumination device is controlled to illuminate the photon counting detector, and the wavelength of the light emitted by the illumination device is within the illumination wavelength range determined according to the defect level generated by the vacancy, so that the hole captured by the vacancy is removed, thereby achieving the effect of eliminating the polarization effect, and solving the problem that the photon counting detector of the photon counting spectrum CT in the related art causes inaccurate counting due to the polarization effect, the counting precision of the photon counting detector in the photon counting energy spectrum CT is improved.
In some embodiments, fig. 3 is a flowchart ii of a method for depolarization of a photon counting detector according to an embodiment of the present application, and as shown in fig. 3, the method for determining an illumination wavelength range of an illumination device according to an energy level of a defect generated during crystal growth includes the following steps:
step S301, determining a photon energy range of the illumination device according to the defect energy level;
it should be noted that the defect level generated by Gd vacancy is approximately 0.75eV above CdTe or CZT valence band, and therefore the photon energy of the illumination device used needs to be greater than 0.75eV to de-trap the trapped hole.
Step S302, determining the illumination wavelength range of the illumination device according to the photon energy range;
where E ═ hc/λ, E is the photon energy, h is the planck constant, c is the speed of light, and λ is the wavelength, the illumination wavelength range of the illumination device can be determined with a known photon energy range.
Through steps S301 to S302, according to the defect energy level generated by the Gd vacancy in the photon counting detector, determining a photon energy range required for obtaining the hole captured by the Gd vacancy to be released, determining an illumination wavelength range of the illumination device under the known photon energy range required by the illumination device, and further ensuring that the hole captured by the Gd vacancy is released under the condition that the photon counting detector is illuminated by the illumination device.
In some of these embodiments, in the case where the photon energy of the illumination device is not less than the Gd vacancy generated defect energy level, the illumination wavelength range may be 1000-1500 nm; the defect energy level generated by Gd vacancy is about 0.75eV (Ev +0.75eV) above the valence band, in principle, a photon larger than 0.75eV (the illumination wavelength is less than 1650nm) can enable holes on the defect energy level to jump back to the valence band, namely, the de-trapping is completed, so that the depolarization of CZT is completed, and the experimental result shows that the good depolarization effect is realized when illumination with the illumination wavelength of 1000-1500nm, and the depolarization effect is the best at 1200nm, so that the infrared light of 1200nm can be used for illumination in the application.
In some embodiments, fig. 4 is a schematic diagram of a positional relationship between an illumination device and a photon counting detector according to an embodiment of the present application, as shown in fig. 4, an illumination device LED is above the photon counting detector, and considering that an anode surface needs to be connected with a readout circuit, so that the illumination device illuminates from a cathode surface of the photon counting detector, and an illumination angle of the illumination device may be preferably within ± 60 °, and a wavelength of the illumination device LED is preferably 1200 nm; the cathode and the anode are required to draw out a current, and the direction of the electron flow is the anode surface, and the opposite direction is the cathode surface.
In some embodiments, fig. 5 is a flowchart three of a method for depolarization of a photon counting detector according to an embodiment of the present application, and as shown in fig. 5, in a case that photon energy of the illumination device is not less than a defect energy level generated by Gd vacancies, the step of controlling the illumination device to illuminate the photon counting detector is as follows:
step S501, the on and off of illumination equipment are periodically switched to illuminate a photon counting detector;
it should be noted that, from the perspective of conveniently switching the illumination devices, the illumination device that illuminates the photon counting detector is preferentially switched periodically, but when the illumination device is switched, a program may be set to control the illumination device to illuminate the photon counting detector intermittently;
through the step S501, under the condition that the illumination device continuously illuminates the photon counting detector, a large number of photo-generated carriers and thermal-excited carriers are generated, so that dark current and noise of the photon counting detector are increased, the illumination device is periodically switched to be turned on and off to illuminate the photon counting detector, and signal noise caused by continuous illumination can be reduced under the condition of realizing a depolarization effect.
In some of these embodiments, fig. 6 is a flowchart four of a method of depolarizing a photon counting detector according to an embodiment of the present application, as shown in fig. 6, the method of periodically switching an illumination device on and off to illuminate a photon counting detector comprising the steps of:
step S601, acquiring the trapping time of the hole and the de-trapping time of the hole de-trapping;
step S602, determining the illumination period of the illumination device according to the capture time and the de-capture timeA period; wherein, the time for capturing and desorbing the holes in the CdTe or CZT crystal is tau respectivelypAnd τd(ii) a It should be noted that the lighting cycle includes the on time and the off time of the lighting device in one cycle.
Step S603, switching the illumination equipment to be switched on and off according to the illumination period to illuminate the photon counting detector;
through the steps S601 to S603, according to the photon counting detector, the time for capturing and desorbing the holes in the CdTe or CZT crystal is taupAnd τdThe irradiation time and the closing time of the illumination device are determined, so that the signal noise caused by continuous irradiation is reduced under the condition that the periodically working illumination device realizes the depolarization effect.
In some embodiments, fig. 7 is a flowchart of a method for acquiring capture time and de-capture time according to an embodiment of the present application, as shown in fig. 7, the method includes the following steps:
step S701, irradiating the photon counting detector by using a preset illumination wavelength, and recording a first time set when the photon counting detector reaches polarization;
it should be noted that, the irradiation of the photon counting detector by using the preset illumination wavelength means that the illumination wavelength of the Gd vacancy trapped cavity in the photon counting detector is simulated, and in the simulation process, the irradiation may be performed by using an LED with a wavelength of 940nm to make the photon counting detector reach a polarization state.
Step S702, irradiating the photon technology detector by using a preset illumination wavelength, and recording a depolarization second time set of the photon counting detector;
it should be noted that, the photon technology detector is irradiated by using a preset illumination wavelength, that is, the illumination wavelength at which a hole captured by a Gd vacancy in the analog photon counting detector is uncaptured, in the simulation process, an LED with a wavelength of 1200nm may be used for irradiation, and the 1200nm LED is periodically switched during the irradiation.
Step S703, determining the capture time and the de-capture time according to the first time set and the second time set;
fig. 8 is a schematic diagram of the distribution of the electric field of the cathode surface of the photon counting detector according to the embodiment of the present application, as shown in fig. 8, the 940nm LED irradiates to make the detector reach a polarization state, and during the simulation period, the 940nm LED is always in an on state, so as to obtain a first time set; the 1200nm LED is used for depolarization, the 1200nm LED is periodically switched in the simulation period to obtain a second time set, the first time set and the second time set are fitted to respectively obtain polarization and depolarization time, taup＝160ms，τd＝65ms。
Through steps S701 to S703, a first data point and a second data point based on the cathode plane electric field are obtained by simulating the photon counting detector to reach the polarization state and the depolarization state, and the first data point and the second data point are fitted to determine the polarization and depolarization time of the photon counting detector, so as to ensure that the accurate time for capturing and desorbing the holes is obtained.
In some embodiments, in the case of periodically switching on and off of the lighting device, the on time of the lighting device may be less than or equal to 20ms, and the off time of the lighting device may be less than or equal to 20ms, for example, the lighting device may be set to be turned on for 20ms, turned off for 20ms, and then turned on for 20ms, and turned off for 20ms for periodic illumination within a certain time period;
it should be noted that the time for capturing and releasing the cavity in the CZT crystal is taupAnd τdIn principle, the frequency at which the lighting device is switched on and off needs to be greater than 1/τpAnd 1/taudThe method can ensure better depolarization effect, and illustratively, the time for capturing and desorbing the holes in the CZT crystal is taup160ms and τd65ms, the frequency at which the lighting device is switched on and off in principle needs to be greater than 1/τp(6Hz) and 1/td(16Hz) can ensure better depolarization effect, and further the on-off frequency of the illumination equipment>A better depolarization effect can be achieved at 25Hz, so in the embodiment of the present application, the frequency of turning on and off the illumination device can be set to be greater than or equal to 25Hz (e.g., 25Hz, 50Hz,100Hz, etc.);
it should be further noted that, because the frequency of turning on and off the illumination device may be set to be greater than or equal to 25Hz (e.g. 25Hz, 50Hz,100Hz, etc.), and because the illumination period of the illumination device includes the turning on time of the illumination device and the turning off time of the illumination device, the illumination period of the illumination device is less than or equal to 40ms, preferably, the turning on time of the illumination device may be less than or equal to 20ms, the turning off time of the illumination device may be less than or equal to 20ms, the turning on time of the illumination device may be equal to the turning off time of the illumination device, e.g. the turning on time of the illumination device is 20ms, and the turning off time of the illumination device is 20; the on-time of the illumination device may not be equal to the off-time of the illumination device, for example, the on-time of the illumination device is 20ms, the off-time of the illumination device is 15ms, and the on-time and the off-time of the illumination device are switched according to the illumination period to illuminate the photon counting detector, so that the photon counting detector is compared with continuous illumination, the polarization phenomenon of semiconductor detectors such as CdTe, CZT and the like in the photon counting detector can be effectively solved, and the noise of the detector cannot be obviously increased.
It should be noted that the steps illustrated in the above-described flow diagrams or in the flow diagrams of the figures may be performed in a computer system, such as a set of computer-executable instructions, and that, although a logical order is illustrated in the flow diagrams, in some cases, the steps illustrated or described may be performed in an order different than here.
The present embodiment further provides a depolarization apparatus of a photon counting detector, which is used to implement the foregoing embodiments and preferred embodiments, and the descriptions already given are omitted. As used hereinafter, the terms "module," "unit," "subunit," and the like may implement a combination of software and/or hardware for a predetermined function. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated.
Fig. 9 is a block diagram of a depolarization apparatus of a photon counting detector according to an embodiment of the present application, and as shown in fig. 9, the depolarization apparatus includes: an illumination wavelength range determination module 90 and a control module 91;
the illumination wavelength range determining module 90 is used for determining the illumination wavelength range of the illumination device according to the defect energy level generated by the Gd vacancy;
and the control module 91 is configured to control the illumination device to illuminate the photon counting detector according to an illumination wavelength range, where holes captured by Gd vacancies in the photon counting detector can be de-captured within the illumination wavelength range.
By the depolarization device of the photon counting detector, because the defect energy level generated by Gd vacancy in the semiconductor forbidden band is the main reason of causing the polarization phenomenon of CdTe and CZT detectors, namely, under the condition that the photon counting detector receives rays, photons in the rays generate holes in the photon counting detector, the cavity is captured by Gd vacancy in the transportation process, the illumination equipment is controlled to irradiate the photon counting detector under the condition that the photon counting detector receives rays, and the wavelength of the light emitted by the illumination equipment is in the illumination wavelength range determined according to the defect energy level generated by Gd vacancies, so that the holes captured by the Gd vacancies are released, the effect of eliminating the polarization effect is achieved, the problem that the photon counting detector of the photon counting energy spectrum CT in the related technology is inaccurate in counting due to the polarization effect is solved, and the counting precision of the photon counting detector in the photon counting energy spectrum CT is improved.
In some embodiments, the illumination wavelength range determining module 90 and the control module 91 are further configured to implement the steps in the method for depolarizing a photon counting detector provided in each of the above embodiments, and are not described herein again.
The above modules may be functional modules or program modules, and may be implemented by software or hardware. For a module implemented by hardware, the modules may be located in the same processor; or the modules can be respectively positioned in different processors in any combination.
The present application further provides a system for depolarization of a photon counting detector, and fig. 10 is a block diagram of a structure of the system for depolarization of a photon counting detector according to an embodiment of the present application, where the system includes a central processing unit 101, a photon counting detector 100, and an illumination device 102;
the central processing unit 101 is used for determining the illumination wavelength range of the illumination device 102 according to the defect energy level generated by the Gd vacancy;
and the central processing unit 101 is further configured to control the illumination device 102 to illuminate the photon counting detector 100 according to an illumination wavelength range, wherein holes captured by Gd vacancies in the photon counting detector can be de-captured in the illumination wavelength range.
By the depolarization system of the photon counting detector, because the defect energy level generated by Gd vacancy in the semiconductor forbidden band is the main reason of causing the polarization phenomenon of CdTe and CZT detectors, namely, under the condition that the photon counting detector receives rays, photons in the rays generate holes in the photon counting detector, the cavity is captured by Gd vacancy in the transportation process, the illumination equipment is controlled to irradiate the photon counting detector under the condition that the photon counting detector receives rays, and the wavelength of the light emitted by the illumination equipment is in the illumination wavelength range determined according to the defect energy level generated by Gd vacancies, so that the holes captured by the Gd vacancies are released, the effect of eliminating the polarization effect is achieved, the problem that the photon counting detector of the photon counting energy spectrum CT in the related technology is inaccurate in counting due to the polarization effect is solved, and the counting precision of the photon counting detector in the photon counting energy spectrum CT is improved.
In some embodiments, the central processing unit 101 is further configured to implement the steps in the method for depolarizing a photon counting detector provided in each of the above embodiments, which are not described herein again.
In one embodiment, a computer device is provided, which may be a terminal. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected by a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The network interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a method of depolarization of a photon counting detector. The display screen of the computer equipment can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer equipment can be a touch layer covered on the display screen, a key, a track ball or a touch pad arranged on the shell of the computer equipment, an external keyboard, a touch pad or a mouse and the like.
In an embodiment, fig. 11 is a schematic internal structural diagram of a computer device according to an embodiment of the present application, and as shown in fig. 11, a computer device is provided, where the computer device may be a server, and its internal structural diagram may be as shown in fig. 11. The computer device includes a processor, a memory, a network interface, and a database connected by a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The database of the computer device is used for storing data. The network interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a method of depolarization of a photon counting detector.
Those skilled in the art will appreciate that the architecture shown in fig. 11 is merely a block diagram of some of the structures associated with the disclosed aspects and is not intended to limit the computing devices to which the disclosed aspects apply, as particular computing devices may include more or less components than those shown, or may combine certain components, or have a different arrangement of components.
In one embodiment, a computer device is provided, which includes a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the computer program to implement the steps of the method for depolarization of a photon counting detector provided in the above embodiments.
In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, which when executed by a processor implements the steps in the method for depolarization of a photon counting detector provided by the various embodiments described above.
It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A method of depolarization of a photon counting detector, the method comprising:
determining the illumination wavelength range of illumination equipment according to the defect energy level generated in the crystal growth process;
and controlling the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range.
2. The method of claim 1, wherein determining the illumination wavelength range of the illumination device according to the defect energy levels generated during the crystal growth process comprises:
determining a photon energy range of the illumination device according to the defect energy level;
and determining the illumination wavelength range of the illumination equipment according to the photon energy range.
3. The method according to claim 1 or 2, wherein the illumination wavelength range is 1000-1500nm in a case where the photon energy of the illumination apparatus is not less than the defect energy level.
4. The method according to claim 1 or 2, wherein in case the photon energy of the illumination device is not less than the defect energy level, the controlling the illumination device to illuminate the photon counting detector is:
periodically switching the illumination device on and off to illuminate the photon counting detector.
5. The method of claim 4, wherein said periodically switching said illumination device on and off to illuminate said photon counting detector comprises:
acquiring a trapping time for a hole to be trapped and a de-trapping time for the hole to be de-trapped;
determining an illumination period of the illumination device according to the capture time and the de-capture time;
switching the illumination device on and off according to the illumination period to illuminate the photon counting detector.
6. The method of claim 5, wherein obtaining the trapping time for the hole to be trapped and obtaining the de-trapping time for the hole to be de-trapped comprises:
irradiating the photon counting detector by using a preset illumination wavelength, and recording a first time set when the photon counting detector reaches polarization;
illuminating the photon technology detector by using a preset illumination wavelength, and recording a depolarization second time set of the photon counting detector;
an acquisition time and a de-acquisition time are determined based on the first time set and the second time set.
7. The method according to claim 4, wherein in case of periodically switching on and off of the illumination device, the on time of the illumination device is less than or equal to 20ms and the off time of the illumination device is less than or equal to 20 ms.
8. A system for depolarization of a photon counting detector, the system comprising a processor, a photon counting detector, and an illumination device;
the processor is used for determining the illumination wavelength range of the illumination equipment according to the defect energy level generated in the crystal growth process;
and the processor controls the illumination equipment to illuminate the photon counting detector according to the illumination wavelength range.
9. A computer device comprising a memory and a processor, characterized in that the memory has stored therein a computer program, the processor being arranged to execute the computer program to perform the method of photon counting detector depolarization according to any of claims 1 to 7.
10. A storage medium, in which a computer program is stored, wherein the computer program is arranged to perform the method of depolarization of a photon counting detector according to any of claims 1 to 7 when executed.
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