Dose monitoring device and beam control device based on scintillation fiber array

Abstract

The embodiment of the invention particularly relates to a dosage monitoring device based on a scintillation fiber array and a beam control device. In the dose monitoring device, when a beam passes through a two-dimensional scintillation optical fiber array detector, a plurality of first scintillation optical fibers arranged in parallel in a first scintillation optical fiber layer and a plurality of second scintillation optical fibers arranged in parallel in a second scintillation optical fiber layer are excited to emit scintillation fluorescence, and the scintillation fluorescence is transmitted along the optical fibers and received by a photoelectric detection unit; and the photocurrent signal is further converted into a voltage pulse signal by the current-voltage conversion unit, and the output dose information and the radiation field dose distribution information of the electron accelerator can be further obtained according to the voltage pulse signal.

Description

Technical Field

[0001] Multiple embodiments of the present specification relate to the field of beam monitoring technology, and specifically to a dose monitoring device and a beam control device based on a scintillating fiber array. Background Art

[0002] The dose monitoring system is an important component of the medical electron accelerator. It is used to detect the output dose rate, cumulative dose, planar dose distribution of the accelerator, and provide detection and control signals for accelerator operation and dose protection. It is crucial to accurately monitor the changes in the output dose and dose distribution of medical electron accelerators in clinical tumor treatment. Radiotherapy technology is developing rapidly. Currently, ultra-high dose rate radiotherapy (Flash radiotherapy) has emerged. The emergence of Flash radiotherapy has brought new challenges to dose monitoring and beam control. The existing dose monitoring system based on ionization chambers corresponds to the dose rate of conventional radiotherapy of 1 to 10 Gy / min (pulse dose rate 10 3 ~10 4 Gy / min) can fully meet the needs of dose monitoring during radiotherapy. However, in the case of ultra-high dose rate (such as Flash radiotherapy), the dose rate is greater than 40Gy / s (pulse dose rate>10 4 Gy / s), due to the compound effect of positive and negative ions and the shielding effect of positive charge, the ionization chamber will become saturated or even unable to work normally.

[0003] Therefore, there is an urgent need for a new monitoring device to more effectively solve the dose monitoring and control problems in radiotherapy. Summary of the invention

[0004] The embodiments of this specification provide a dose monitoring device and a beam control device based on a scintillating fiber array, which can accurately monitor the output dose information and field dose distribution information of an electron accelerator.

[0005] The technical solution is as follows:

[0006] In a first aspect, an embodiment of the present specification provides a dose monitoring device based on a scintillation fiber array, comprising a first scintillation fiber layer and a second scintillation fiber layer arranged vertically, and the arrangement direction of the first scintillation fiber layer is perpendicular to the arrangement direction of the second scintillation fiber layer, so as to form a one-dimensional scintillation fiber array detector;

[0007] The first scintillation fiber layer includes a first scintillation fiber module and a first signal processing module connected to the first scintillation fiber module;

[0008] The second scintillation fiber layer includes a second scintillation fiber module and a second signal processing module connected to the second scintillation fiber module;

[0009] The first scintillation optical fiber module comprises a plurality of first scintillation optical fibers arranged in parallel, and the second scintillation optical fiber module comprises a plurality of second scintillation optical fibers arranged in parallel, and the arrangement direction of the second scintillation optical fibers is perpendicular to the arrangement direction of the first scintillation optical fibers;

[0010] The first signal processing module includes a first photoelectric detection unit and a first current-voltage conversion unit connected in sequence, and the first photoelectric detection unit is connected to the first scintillation optical fiber module;

[0011] The second signal processing module includes a second photoelectric detection unit and a second current-voltage conversion unit connected in sequence, and the second photoelectric detection unit is connected to the second scintillation optical fiber module;

[0012] The dosage monitoring device further includes a third signal processing module connected to the first current-voltage conversion unit and the second current-voltage conversion unit respectively;

[0013] The third signal processing module obtains the accelerator output dose information and the field dose distribution information based on the first voltage pulse signal output by the first current-voltage conversion unit and the second voltage pulse signal output by the second current-voltage conversion unit.

[0014] As a preferred solution, the third signal processing module includes a first signal amplifying unit, a second signal amplifying unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, and a signal processing unit;

[0015] The first signal amplifying unit, the first analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the first signal amplifying unit is also connected to the first current-voltage conversion unit;

[0016] The second signal amplifying unit, the second analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the second signal amplifying unit is also connected to the second current-voltage conversion unit;

[0017] The first signal amplifying unit performs signal amplification processing on the first voltage pulse signal to obtain a first voltage pulse amplified signal;

[0018] The first analog-to-digital conversion unit performs analog-to-digital conversion processing on the first voltage pulse amplified signal to obtain a first voltage pulse digital signal;

[0019] The second signal amplifying unit performs signal amplification processing on the second voltage pulse signal to obtain a second voltage pulse amplified signal;

[0020] The second analog-to-digital conversion unit performs analog-to-digital conversion processing on the second voltage pulse amplified signal to obtain a second voltage pulse digital signal;

[0021] The signal processing unit obtains the accelerator output dose information and the radiation field dose distribution information based on the first voltage pulse digital signal and the second voltage pulse digital signal.

[0022] As a preferred solution, the accelerator output dose information includes output dose size information and output dose rate information.

[0023] As a preferred solution, the first scintillation optical fiber module includes a plurality of first detection areas arranged in sequence, each of which has a plurality of first scintillation optical fibers corresponding to each other; the second scintillation optical fiber module includes a plurality of second detection areas arranged in sequence, each of which has a plurality of second scintillation optical fibers corresponding to each other;

[0024] The first photoelectric detection unit includes a plurality of first photoelectric detection sub-units, the number of which is the same as the number of the first detection areas and which are respectively connected to the plurality of first detection areas in pairs;

[0025] The first current-voltage conversion unit includes a plurality of first current-voltage conversion sub-units, the number of which is the same as the number of the first photoelectric detection sub-units and which are respectively connected to the plurality of first photoelectric detection sub-units in pairs;

[0026] The second photoelectric detection unit includes a plurality of second photoelectric detection sub-units whose number is the same as the number of the second detection areas and which are respectively connected to the plurality of second detection areas in pairs;

[0027] The second current-voltage conversion unit includes a plurality of second current-voltage conversion sub-units whose number is the same as the number of the second photoelectric detection sub-units and which are respectively connected to the plurality of second photoelectric detection sub-units in pairs;

[0028] The third signal processing module is respectively connected to multiple first current-voltage conversion subunits and multiple second current-voltage conversion subunits, and obtains accelerator output dose information and field dose distribution information based on multiple first voltage pulse sub-signals output by the multiple first current-voltage conversion subunits and multiple second voltage pulse sub-signals output by the multiple second current-voltage conversion subunits.

[0029] As a preferred solution, the plurality of first photodetection subunits each include a first avalanche photodiode, a second avalanche photodiode, and a first adding circuit respectively connected to the first avalanche photodiode and the second avalanche photodiode, wherein the first adding circuit is also connected to a first current-voltage conversion subunit corresponding to the first photodetection subunit to which it belongs; the first avalanche photodiode is respectively connected to one end of a plurality of first scintillation optical fibers in a first detection zone corresponding to the first photodetection subunit to which it belongs, and the second avalanche photodiode is respectively connected to the other end of a plurality of first scintillation optical fibers in a first detection zone corresponding to the first photodetection subunit to which it belongs;

[0030] Multiple second photodetection sub-units all include a third avalanche photodiode, a fourth avalanche photodiode, and a second adding circuit respectively connected to the third avalanche photodiode and the fourth avalanche photodiode, and the second adding circuit is also connected to the second current-voltage conversion sub-unit corresponding to the second photodetection sub-unit to which it belongs; the third avalanche photodiode is respectively connected to one end of multiple second scintillation optical fibers in the second detection area corresponding to the second photodetection sub-unit to which it belongs, and the fourth avalanche photodiode is respectively connected to the other end of the multiple second scintillation optical fibers in the second detection area corresponding to the second photodetection sub-unit to which it belongs.

[0031] As a preferred solution, the first scintillation optical fiber module includes three first detection areas arranged in sequence; the second scintillation optical fiber module includes three second detection areas arranged in sequence;

[0032] Furthermore, the first detection zone located at the middle position among the three first detection zones and the second detection zone located at the middle position among the three second detection zones have overlapping areas.

[0033] As a preferred solution, the number of first scintillation optical fibers in multiple first detection areas is consistent, and the intervals between the first scintillation optical fibers in multiple first detection areas are consistent;

[0034] The number of the second scintillation optical fibers in the plurality of second detection zones is consistent, and the intervals between the second scintillation optical fibers in the plurality of second detection zones are consistent.

[0035] As a preferred solution, the number of first scintillation optical fibers in the first detection zone is also consistent with the number of second scintillation optical fibers in the second detection zone;

[0036] The size of the arrangement interval of the first scintillation optical fibers in the first detection zone is also consistent with the size of the arrangement interval of the second scintillation optical fibers in the second detection zone.

[0037] As a preferred solution, the dose monitoring device further comprises a cubic frame, and the first scintillating optical fiber layer and the second scintillating optical fiber layer are vertically arranged in the cubic frame.

[0038] In a second aspect, an embodiment of the present specification provides a beam control device, including an electron accelerator that generates a beam, a dose monitoring device based on a scintillation fiber array as described in the first aspect of the above embodiment, and a parameter adjustment module that adjusts the operating parameters of the electron accelerator based on the accelerator output dose information and field dose distribution information obtained by the dose monitoring device.

[0039] The beneficial effects brought by the technical solutions provided by some embodiments of this specification include at least:

[0040] When the beam passes through the two-dimensional scintillation fiber array detector, multiple first scintillation fibers arranged in parallel in the first scintillation fiber layer and multiple second scintillation fibers arranged in parallel in the second scintillation fiber layer are excited to emit scintillation fluorescence, which is transmitted along the optical fiber and received by the photoelectric detection unit, converted into a photocurrent signal, and further converted into a voltage pulse signal by the current-voltage conversion unit. Further, the output dose information and field dose distribution information of the electron accelerator can be obtained according to the voltage pulse signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a schematic diagram of the structure of a dose monitoring device based on a scintillation fiber array provided in an embodiment of this specification.

[0043] Figure 2 It is a schematic diagram of the system architecture of a dose monitoring device based on a scintillation fiber array provided in an embodiment of this specification.

[0044] Figure 3 It is a schematic diagram of the system architecture of a beam control device provided in an embodiment of this specification.

[0045] In the figure: 1, cube frame; 2, beam; 3, first scintillation fiber layer; 31, first scintillation fiber module; 321, first avalanche photodiode; 322, second avalanche photodiode; 4, second scintillation fiber layer; 41, second scintillation fiber module; 421, third avalanche photodiode. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of this specification will be described clearly and completely below in conjunction with the drawings in the embodiments of this specification.

[0047] The terms "first", "second", "third", etc. in the description and claims of this specification and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0048] The following description provides examples and does not limit the scope, applicability or examples set forth in the claims. Changes may be made to the functions and arrangements of the elements described without departing from the scope of the present specification. Various processes or components may be appropriately omitted, substituted or added to each example. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted or combined. In addition, features described with respect to some examples may be combined in other examples.

[0049] Reference Figure 1 , Figure 2 , which is a schematic diagram of the structure and system architecture of a dose monitoring device based on a scintillation fiber array provided in one or more embodiments of this specification.

[0050] The dose monitoring device may at least include a first scintillating optical fiber layer 3 and a second scintillating optical fiber layer 4 arranged vertically, and the arrangement direction of the first scintillating optical fiber layer 3 is perpendicular to the arrangement direction of the second scintillating optical fiber layer 4;

[0051] The first scintillation fiber layer 3 includes a first scintillation fiber module 31 and a first signal processing module connected to the first scintillation fiber module 31;

[0052] The second scintillation fiber layer 4 includes a second scintillation fiber module 41 and a second signal processing module connected to the second scintillation fiber module 41;

[0053] The first scintillation optical fiber module 31 includes a plurality of first scintillation optical fibers arranged in parallel, and the second scintillation optical fiber module 41 includes a plurality of second scintillation optical fibers arranged in parallel, and the arrangement direction of the second scintillation optical fibers is perpendicular to the arrangement direction of the first scintillation optical fibers (that is, the arrangement directions of the first scintillation optical fibers and the second scintillation optical fibers are also perpendicular);

[0054] The first signal processing module includes a first photoelectric detection unit and a first current-voltage conversion unit connected in sequence, and the first photoelectric detection unit is connected to the first scintillation optical fiber module 31;

[0055] The second signal processing module includes a second photoelectric detection unit and a second current-voltage conversion unit connected in sequence, and the second photoelectric detection unit is connected to the second scintillation optical fiber module 41;

[0056] The dosage monitoring device further includes a third signal processing module connected to the first current-voltage conversion unit and the second current-voltage conversion unit respectively;

[0057] The third signal processing module obtains the accelerator output dose information and the field dose distribution information based on the first voltage pulse signal output by the first current-voltage conversion unit and the second voltage pulse signal output by the second current-voltage conversion unit.

[0058] The accelerator output dose information includes output dose size information and output dose rate information.

[0059] The dose monitoring device further comprises a cubic frame 1 , in which the first scintillating optical fiber layer 3 and the second scintillating optical fiber layer 4 are vertically arranged up and down.

[0060] In the dose monitoring device provided in the embodiment of the present specification, when the beam 2 passes through the two-dimensional scintillation fiber array detector, the multiple first scintillation fibers arranged in parallel in the first scintillation fiber layer 31 and the multiple second scintillation fibers arranged in parallel in the second scintillation fiber layer 41 are excited to emit scintillation fluorescence, which is transmitted along the optical fiber and received by the photoelectric detection unit, converted into a photocurrent signal, and further converted into a voltage pulse signal by the current-voltage conversion unit. Further, the output dose information and field dose distribution information of the electron accelerator can be obtained according to the voltage pulse signal.

[0061] Measurement principle: The beam passes through the scintillator and deposits energy in the scintillator. The number of photons emitted by the scintillator is proportional to the energy deposited in the scintillator. Under certain conditions, the energy deposited in the scintillation detector is directly related to the dose. Once the conditions are determined, the intensity of the light emitted by the scintillator can be converted into the dose value under the determined conditions.

[0062] It is understandable that each optical fiber emits scintillation fluorescence due to beam irradiation, so the scintillation fluorescence intensity of each optical fiber corresponds to the beam irradiation condition. Then, the distribution of the beam output dose on the entire plane can be reflected according to the scintillation fluorescence intensity of each optical fiber (because the device includes a plurality of first scintillation optical fibers and a plurality of second scintillation optical fibers arranged vertically).

[0063] It is understandable that the scintillation fluorescence intensity of the scintillation fiber in the first scintillation fiber layer 31 or the scintillation fluorescence intensity of the scintillation fiber in the second scintillation fiber layer 41 can reflect the output dose size information and output dose rate information of the electron accelerator. The scintillation fiber is preferably made of plastic.

[0064] Reference Figure 2 As shown, in one embodiment of the present specification, the third signal processing module includes a first signal amplifying unit, a second signal amplifying unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, and a signal processing unit;

[0065] The first signal amplifying unit, the first analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the first signal amplifying unit is also connected to the first current-voltage conversion unit;

[0066] The second signal amplifying unit, the second analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the second signal amplifying unit is also connected to the second current-voltage conversion unit;

[0067] The first signal amplifying unit performs signal amplification processing on the first voltage pulse signal to obtain a first voltage pulse amplified signal;

[0068] The first analog-to-digital conversion unit performs analog-to-digital conversion processing on the first voltage pulse amplified signal to obtain a first voltage pulse digital signal;

[0069] The second signal amplifying unit performs signal amplification processing on the second voltage pulse signal to obtain a second voltage pulse amplified signal;

[0070] The second analog-to-digital conversion unit performs analog-to-digital conversion processing on the second voltage pulse amplified signal to obtain a second voltage pulse digital signal;

[0071] The signal processing unit obtains the accelerator output dose information and the radiation field dose distribution information based on the first voltage pulse digital signal and the second voltage pulse digital signal.

[0072] Through signal amplification and analog-to-digital conversion operations, the dose monitoring device is made more resistant to interference and the signal-to-noise ratio is improved.

[0073] Reference Figure 2 As shown, in one embodiment of the present specification, the first scintillation optical fiber module includes a plurality of first detection areas arranged in sequence, each of which has a plurality of first scintillation optical fibers corresponding to each other; the second scintillation optical fiber module includes a plurality of second detection areas arranged in sequence, each of which has a plurality of second scintillation optical fibers corresponding to each other;

[0074] The first photoelectric detection unit includes a plurality of first photoelectric detection sub-units, the number of which is the same as the number of the first detection areas and which are respectively connected to the plurality of first detection areas in pairs;

[0075] The first current-voltage conversion unit includes a plurality of first current-voltage conversion sub-units, the number of which is the same as the number of the first photoelectric detection sub-units and which are respectively connected to the plurality of first photoelectric detection sub-units in pairs;

[0076] The second photoelectric detection unit includes a plurality of second photoelectric detection sub-units whose number is the same as the number of the second detection areas and which are respectively connected to the plurality of second detection areas in pairs;

[0077] The second current-voltage conversion unit includes a plurality of second current-voltage conversion sub-units whose number is the same as the number of the second photoelectric detection sub-units and which are respectively connected to the plurality of second photoelectric detection sub-units in pairs;

[0078] The third signal processing module is respectively connected to multiple first current-voltage conversion sub-units and multiple second current-voltage conversion sub-units, and obtains output dose information and dose distribution information based on multiple first voltage pulse sub-signals output by the multiple first current-voltage conversion sub-units and multiple second voltage pulse sub-signals output by the multiple second current-voltage conversion sub-units (that is, at this time, the first signal amplification unit in the third signal processing module should include multiple first signal amplification sub-units whose number is consistent with the number of first detection zones, and the first analog-to-digital conversion unit in the third signal processing module should also include multiple first analog-to-digital conversion sub-units whose number is consistent with the number of first detection zones, and the same applies to the second signal amplification unit and the second analog-to-digital conversion unit).

[0079] It is understandable that if a separate photodetection subunit is provided for each scintillation fiber, the effect of detecting the dose distribution is of course better, but the electronic part of the entire dose measurement system is too complicated and the cost is relatively high, and the dose monitoring and control of the medical accelerator does not require such high precision. Therefore, in this embodiment, multiple scintillation fibers can be combined and read out according to the requirements for the accuracy of dose distribution monitoring. That is, one photodetection subunit corresponds to multiple scintillation fibers in one detection area.

[0080] Assuming that the setting direction of the first scintillation fiber layer is the X-axis and the setting direction of the second scintillation fiber layer is the Y-axis, the current pulse signals corresponding to the multiple first detection areas in the first scintillation fiber module can reflect the dose sizes corresponding to the multiple first detection areas, and the current pulse signals corresponding to the multiple second detection areas in the second scintillation fiber module can reflect the dose sizes corresponding to the multiple second detection areas, thereby knowing the dose sizes of the beam at various positions on the X-axis and the Y-axis, and thereby obtaining the field dose distribution information, such as distribution symmetry.

[0081] The output dose size can be obtained based on the dose size corresponding to the first detection area located at the center of the first scintillation fiber optic module, or based on the dose size corresponding to the second detection area located at the center of the second scintillation fiber optic module. It is preferred to use the detection area through which the beam passes first.

[0082] Reference Figure 2 As shown, the dose monitoring device is installed under the X-ray homogenizer (or electron beam scattering foil), and the center of the dose monitoring device is located at the center of the beam line. The plane of the dose monitoring device is perpendicular to the accelerator beam direction.

[0083] The dose size and output dose rate corresponding to the detection area can be calculated based on the number of pulses of the first voltage pulse sub-signal or the second voltage pulse sub-signal within a preset time, and the signal amplitude of each pulse within the preset time.

[0084] Reference Figure 1 As shown, in one embodiment of the present specification, the plurality of first photodetection sub-units each include a first avalanche photodiode 321, a second avalanche photodiode 322, and a first adding circuit respectively connected to the first avalanche photodiode 321 and the second avalanche photodiode 322 (Note: Figure 1 , Figure 2 The first adding circuit and the second adding circuit are not shown in the figure), the first adding circuit is also connected to the first current-voltage conversion subunit corresponding to the first photodetection subunit to which it belongs; the first avalanche photodiode 321 is respectively connected to one end of the plurality of first scintillation optical fibers in the first detection area corresponding to the first photodetection subunit to which it belongs, and the second avalanche photodiode 322 is respectively connected to the other end of the plurality of first scintillation optical fibers in the first detection area corresponding to the first photodetection subunit to which it belongs;

[0085] The plurality of second photodetection sub-units each include a third avalanche photodiode 421, a fourth avalanche photodiode (Note: Figure 1 Due to viewing angle problems, the fourth avalanche photodiode is not shown. In fact, the fourth avalanche photodiode is located opposite to the third avalanche photodiode 421) and a second adding circuit respectively connected to the third avalanche photodiode 421 and the fourth avalanche photodiode, the second adding circuit is also connected to the second current-voltage conversion subunit corresponding to the second photodetection subunit to which it belongs; the third avalanche photodiode 421 is respectively connected to one end of a plurality of second scintillation optical fibers in the second detection area corresponding to the second photodetection subunit to which it belongs, and the fourth avalanche photodiode is respectively connected to the other end of a plurality of second scintillation optical fibers in the second detection area corresponding to the second photodetection subunit to which it belongs.

[0086] That is, the photoelectric detection subunit is composed of two avalanche photodiodes respectively connected to the two ends of the optical fiber and an adding circuit.

[0087] Reference Figure 2 As shown, in one embodiment of the present specification, the first scintillation optical fiber module includes three first detection areas arranged in sequence; the second scintillation optical fiber module includes three second detection areas arranged in sequence;

[0088] Furthermore, the first detection zone located at the middle position among the three first detection zones and the second detection zone located at the middle position among the three second detection zones have overlapping areas.

[0089] The number of first scintillation optical fibers in the plurality of first detection zones is consistent, and the intervals between the first scintillation optical fibers in the plurality of first detection zones are consistent;

[0090] The number of second scintillation optical fibers in the plurality of second detection zones is consistent, and the intervals between the second scintillation optical fibers in the plurality of second detection zones are consistent;

[0091] The number of first scintillation optical fibers in the first detection zone is also consistent with the number of second scintillation optical fibers in the second detection zone;

[0092] The size of the arrangement interval of the first scintillation optical fibers in the first detection zone is also consistent with the size of the arrangement interval of the second scintillation optical fibers in the second detection zone.

[0093] In this embodiment, the distribution uniformity of the scintillation optical fibers in the entire dose monitoring device is ensured, further improving the accuracy of monitoring.

[0094] Specifically,

[0095] The scintillating fiber can be a fiber with a circular cross section (diameter 0.25mm) or a square cross section (side length 0.25mm), with a scintillating fiber arranged every 1mm, and a fiber length of 5cm. The selection requirements of plastic scintillating fiber are: select scintillating fiber with high scintillating efficiency, select scintillating fiber with low light attenuation, and preferably select scintillating fiber with green light wavelength, thereby increasing the conversion efficiency of avalanche photodiode (APD).

[0096] The dose monitoring device provided in multiple embodiments of this specification is:

[0097] The scintillation optical fiber itself is both a beam detection element and a scintillation fluorescence collection device, which solves the problem of difficulty in collecting scintillation light.

[0098] The cross-section of the scintillating optical fiber is small, and it is a penetrating detector, but its effect on the radiation beam is small and can be ignored.

[0099] The dose monitoring device has a unique structure and can comprehensively obtain the output dose information and field dose distribution information of the medical accelerator. It can replace the ionization chamber as a dose monitoring detector for the medical electron accelerator.

[0100] The entire monitoring device has high stability and repeatability, and can adapt to the beam measurement needs in different environments. It can be used to monitor X-ray beams as well as electron beams. It can be used for dose monitoring in conventional radiotherapy as well as for dose monitoring at ultra-high dose rates.

[0101] It can accurately extract key data such as the accelerator's output dose, field dose distribution, and pulse number from the collected original signals, providing a more reliable basis for accelerator beam control during radiotherapy.

[0102] Scalability: Depending on the measurement object, the width of the scintillation fiber array, the diameter (or side length) of the scintillation fiber, the length of each scintillation fiber, the spacing between the scintillation fibers, and the selection of several scintillation fibers for combined readout can be changed to meet the needs of different accelerator dose monitoring.

[0103] See next Figure 3 , Figure 3 A schematic structural diagram of a beam control device 300 provided in an embodiment of this specification is shown.

[0104] The beam control device 300 may include at least an electron accelerator 301 for generating a beam, a dose monitoring device 303 as described in the above embodiment, and a parameter adjustment module 302 for adjusting operating parameters of the electron accelerator 301 based on accelerator output dose information and field dose distribution information obtained by the dose monitoring device 303 .

[0105] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the beam control device embodiment, since it is basically similar to the dose monitoring device embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the dose monitoring device embodiment.

[0106] The embodiments described above are merely preferred embodiments of this specification and are not intended to limit the scope of this specification. Without departing from the design spirit of this specification, various modifications and improvements made to the technical solutions of this specification by ordinary technicians in this field should fall within the scope of protection determined by the claims of this specification.

Claims

1. A dose monitoring device based on a scintillation fiber array, characterized in that: It comprises a first scintillating optical fiber layer and a second scintillating optical fiber layer which are arranged vertically, and the arrangement direction of the first scintillating optical fiber layer is perpendicular to the arrangement direction of the second scintillating optical fiber layer; The first scintillation fiber layer includes a first scintillation fiber module and a first signal processing module connected to the first scintillation fiber module; The second scintillation fiber layer includes a second scintillation fiber module and a second signal processing module connected to the second scintillation fiber module; The first scintillation optical fiber module comprises a plurality of first scintillation optical fibers arranged in parallel, and the second scintillation optical fiber module comprises a plurality of second scintillation optical fibers arranged in parallel, and the arrangement direction of the second scintillation optical fibers is perpendicular to the arrangement direction of the first scintillation optical fibers; The first signal processing module includes a first photoelectric detection unit and a first current-voltage conversion unit connected in sequence, and the first photoelectric detection unit is connected to the first scintillation optical fiber module; The second signal processing module includes a second photoelectric detection unit and a second current-voltage conversion unit connected in sequence, and the second photoelectric detection unit is connected to the second scintillation optical fiber module; The dosage monitoring device further includes a third signal processing module connected to the first current-voltage conversion unit and the second current-voltage conversion unit respectively; The third signal processing module obtains the accelerator output dose information and the field dose distribution information based on the first voltage pulse signal output by the first current-voltage conversion unit and the second voltage pulse signal output by the second current-voltage conversion unit.

2. A dose monitoring device based on a scintillation fiber array according to claim 1, characterized in that: The third signal processing module includes a first signal amplifying unit, a second signal amplifying unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, and a signal processing unit; The first signal amplifying unit, the first analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the first signal amplifying unit is also connected to the first current-voltage conversion unit; The second signal amplifying unit, the second analog-to-digital conversion unit, and the signal processing unit are connected in sequence, and the second signal amplifying unit is also connected to the second current-voltage conversion unit; The first signal amplifying unit performs signal amplification processing on the first voltage pulse signal to obtain a first voltage pulse amplified signal; The first analog-to-digital conversion unit performs analog-to-digital conversion processing on the first voltage pulse amplified signal to obtain a first voltage pulse digital signal; The second signal amplifying unit performs signal amplification processing on the second voltage pulse signal to obtain a second voltage pulse amplified signal; The second analog-to-digital conversion unit performs analog-to-digital conversion processing on the second voltage pulse amplified signal to obtain a second voltage pulse digital signal; The signal processing unit obtains the accelerator output dose information and the radiation field dose distribution information based on the first voltage pulse digital signal and the second voltage pulse digital signal.

3. A dose monitoring device based on a scintillation fiber array according to claim 2, characterized in that: The accelerator output dose information includes output dose size information and output dose rate information.

4. A dose monitoring device based on a scintillation fiber array according to claim 1, characterized in that: The first scintillation optical fiber module comprises a plurality of first detection areas arranged in sequence, each of which has a plurality of first scintillation optical fibers corresponding to the first detection areas; the second scintillation optical fiber module comprises a plurality of second detection areas arranged in sequence, each of which has a plurality of second scintillation optical fibers corresponding to the second detection areas; The first photoelectric detection unit includes a plurality of first photoelectric detection sub-units, the number of which is the same as the number of the first detection areas and which are respectively connected to the plurality of first detection areas in pairs; The first current-voltage conversion unit includes a plurality of first current-voltage conversion sub-units, the number of which is the same as the number of the first photoelectric detection sub-units and which are respectively connected to the plurality of first photoelectric detection sub-units in pairs; The second photoelectric detection unit includes a plurality of second photoelectric detection sub-units whose number is the same as the number of the second detection areas and which are respectively connected to the plurality of second detection areas in pairs; The second current-voltage conversion unit includes a plurality of second current-voltage conversion sub-units whose number is the same as the number of the second photoelectric detection sub-units and which are respectively connected to the plurality of second photoelectric detection sub-units in pairs; The third signal processing module is respectively connected to multiple first current-voltage conversion subunits and multiple second current-voltage conversion subunits, and obtains accelerator output dose information and field dose distribution information based on multiple first voltage pulse sub-signals output by the multiple first current-voltage conversion subunits and multiple second voltage pulse sub-signals output by the multiple second current-voltage conversion subunits.

5. A dose monitoring device based on a scintillation fiber array according to claim 4, characterized in that: The plurality of first photodetection subunits each include a first avalanche photodiode, a second avalanche photodiode, and a first adding circuit respectively connected to the first avalanche photodiode and the second avalanche photodiode, wherein the first adding circuit is also connected to a first current-voltage conversion subunit corresponding to the first photodetection subunit to which it belongs; the first avalanche photodiode is respectively connected to one end of a plurality of first scintillation optical fibers in a first detection area corresponding to the first photodetection subunit to which it belongs, and the second avalanche photodiode is respectively connected to the other end of a plurality of first scintillation optical fibers in a first detection area corresponding to the first photodetection subunit to which it belongs; Multiple second photodetection sub-units all include a third avalanche photodiode, a fourth avalanche photodiode, and a second adding circuit respectively connected to the third avalanche photodiode and the fourth avalanche photodiode, and the second adding circuit is also connected to the second current-voltage conversion sub-unit corresponding to the second photodetection sub-unit to which it belongs; the third avalanche photodiode is respectively connected to one end of multiple second scintillation optical fibers in the second detection area corresponding to the second photodetection sub-unit to which it belongs, and the fourth avalanche photodiode is respectively connected to the other end of the multiple second scintillation optical fibers in the second detection area corresponding to the second photodetection sub-unit to which it belongs.

6. A dose monitoring device based on a scintillation fiber array according to claim 5, characterized in that: The first scintillation optical fiber module comprises three first detection areas arranged in sequence; the second scintillation optical fiber module comprises three second detection areas arranged in sequence; Furthermore, the first detection zone located at the middle position among the three first detection zones and the second detection zone located at the middle position among the three second detection zones have overlapping areas.

7. A dose monitoring device based on a scintillation fiber array according to claim 6, characterized in that: The number of first scintillation optical fibers in the plurality of first detection zones is consistent, and the intervals between the first scintillation optical fibers in the plurality of first detection zones are consistent; The number of the second scintillation optical fibers in the plurality of second detection zones is consistent, and the intervals between the second scintillation optical fibers in the plurality of second detection zones are consistent.

8. A dose monitoring device based on a scintillation fiber array according to claim 7, characterized in that: The number of first scintillation optical fibers in the first detection zone is also consistent with the number of second scintillation optical fibers in the second detection zone; The size of the arrangement interval of the first scintillation optical fibers in the first detection zone is also consistent with the size of the arrangement interval of the second scintillation optical fibers in the second detection zone.

9. A dose monitoring device based on a scintillation fiber array according to claim 1, characterized in that: The dose monitoring device also includes a cubic frame, and the first scintillating optical fiber layer and the second scintillating optical fiber layer are vertically arranged in the cubic frame.

10. A beam control device, characterized in that: It comprises an electron accelerator for generating a beam, a dose monitoring device based on a scintillating fiber array as claimed in any one of claims 1 to 9, and a parameter adjustment module for adjusting the operating parameters of the electron accelerator based on the accelerator output dose information and field dose distribution information obtained by the dose monitoring device.

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