WO2003101528A2 - Dispositif et procede d'inspection d'un faisceau ionisant - Google Patents
Dispositif et procede d'inspection d'un faisceau ionisant Download PDFInfo
- Publication number
- WO2003101528A2 WO2003101528A2 PCT/FR2003/001639 FR0301639W WO03101528A2 WO 2003101528 A2 WO2003101528 A2 WO 2003101528A2 FR 0301639 W FR0301639 W FR 0301639W WO 03101528 A2 WO03101528 A2 WO 03101528A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- scintillator
- light
- image
- inspection head
- inspection
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 13
- 238000007689 inspection Methods 0.000 claims abstract description 63
- 239000000463 material Substances 0.000 claims abstract description 23
- 238000001959 radiotherapy Methods 0.000 claims abstract description 10
- 230000005855 radiation Effects 0.000 claims description 39
- 238000004364 calculation method Methods 0.000 claims description 13
- 230000003595 spectral effect Effects 0.000 claims description 11
- 230000005865 ionizing radiation Effects 0.000 claims description 7
- 238000001228 spectrum Methods 0.000 claims description 6
- 238000009792 diffusion process Methods 0.000 claims description 5
- 230000000694 effects Effects 0.000 claims description 4
- 239000004973 liquid crystal related substance Substances 0.000 claims description 4
- 230000015572 biosynthetic process Effects 0.000 claims description 3
- 238000003384 imaging method Methods 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 claims description 2
- 230000010287 polarization Effects 0.000 claims 1
- 239000007787 solid Substances 0.000 abstract 1
- 238000010521 absorption reaction Methods 0.000 description 7
- 206010028980 Neoplasm Diseases 0.000 description 5
- 230000003071 parasitic effect Effects 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 239000000835 fiber Substances 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 230000006872 improvement Effects 0.000 description 3
- 238000013507 mapping Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 239000013307 optical fiber Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 230000008033 biological extinction Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000004980 dosimetry Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 1
- 229920005372 Plexiglas® Polymers 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 239000004926 polymethyl methacrylate Substances 0.000 description 1
- 229920002102 polyvinyl toluene Polymers 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
- 239000012780 transparent material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/02—Dosimeters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/169—Exploration, location of contaminated surface areas
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/22—Measuring radiation intensity with Cerenkov detectors
Definitions
- the present invention relates to a method and a device for inspecting an ionizing beam. It also relates to dosimetry and radiotherapy devices implementing beam inspection.
- the invention finds applications in general for any inspection or mapping operation of an ionizing beam. In particular, it finds applications in the adjustment and control of medical equipment such as radiotherapy equipment.
- Radiotherapy is a medical treatment technique consisting essentially of irradiating tissue using ionizing radiation such as X, ⁇ and / or ⁇ radiation.
- ionizing radiation such as X, ⁇ and / or ⁇ radiation.
- One of the purposes of irradiation is to destroy a patient's cancerous tumors.
- the ionizing beams are generally not monochromatic but consist of a mixture of radiations of different energies.
- the composition of the beams is sensitive to obstacles, for example, diaphragms, encountered on their trajectory.
- the dose of radiation received by a tissue or by a given region of a tissue depends on a large number of parameters which are difficult to predict. It is difficult to predict exactly and entirely by calculation the dose received at each point of an irradiated volume.
- the beams are inspected to determine the dose of radiation that they are likely to deposit at any point of a body which is subjected to it.
- a first type of known inspection device comprises gas ionization chambers which can be moved in a beam. These chambers are not, however, sensitive to all of the radiative components of an ionization beam to which they are subjected, and exhibit a different absorption behavior than that of living tissue capable of being irradiated. In addition, the ionization chambers do not account for a phenomenon of diffusion of radiation by tissues neighboring an explored area. As a result, the ionization yield of the chambers is different from a dose yield received by a tissue exposed under the same conditions. To account for this correctly, these chambers must be immersed in a liquid - water - with a characteristic substantially similar to that of living tissue.
- Another type of inspection device includes liquid ionization chambers placed in the field of a beam.
- the use of a liquid makes it possible to give the chambers an absorption behavior much closer to that of living tissues.
- a weak mobility of the ions in the liquid, and parasitic phenomena of recombination of the ions formed by the radiation make that the response of these inspection devices is slow and nonlinear.
- scintillator inspection devices are known. These devices include a multitude scintillators each associated with an optical fiber. The role of this optical fiber is to relay the signal outside the beam in order to be able to read it in an environment not polluted by ionizing radiation.
- a bundle of optical fibers constitutes an inspection head. The bundle may alternately comprise scintillating fibers and non-scintillating fibers.
- Such devices have a very high manufacturing cost, linked in particular to the arrangement of the fibers.
- the resolution of the devices is limited by the size of each individual scintillator and their number. In this case the number of fibers and their diameter.
- the object of the invention is to propose a beam inspection device which does not have the limitations or difficulties mentioned above.
- One aim is in particular to propose a simple inspection device, relatively inexpensive, and which makes it possible to accurately account for the doses liable to be deposited by a beam in a living tissue.
- Another goal is to propose a device freed from the parasitic effects of Cerenkov light.
- the invention also aims to provide beam inspection methods and dosimetry and radiotherapy devices implementing these methods.
- the invention more specifically relates to an inspection device for one or more beams with: - an inspection head comprising a scintillator - material reacting to the presence of radiation by an emission of light - and at least one ionizing radiation diffuser associated with the scintillator, a first means for forming at least one image corresponding to at least part of the inspection head comprising the scintillator.
- the scintillator comprises at least one massive and substantially homogeneous plate of scintillation material having two opposite main faces.
- the diffuser block covers at least one of the main faces of the scintillator plate.
- Said device further comprises means for discriminating between the scintillation light and a stray Cerenkov light in the inspection head.
- the resolution of the device is no longer linked to the construction of the scintillator. It essentially depends on the image that one forms of the scintillator plate.
- the use of a massive and substantially scintillator homogeneous considerably reduces its manufacturing cost.
- the scintillator plate is preferably very thin. It is, for example, formed by a film with a thickness of between 1 and 5 mm and the main faces of which have a surface of between 100 and 900 cm 2 .
- the plate can be generally circular or rectangular.
- the plate makes it possible, by its scintillation properties, to account, according to the plane it defines, for the radiation dose received at each of its points.
- the intensity of the scintillation light at any point on the scintillator plate is in fact linked to the dose received.
- the plate thus makes it possible, in a way, to "cut" the beam along a plane.
- the device can incidentally be equipped with relative displacement means between the inspection head and the source of a beam to be inspected.
- the displacement by translation or by rotation makes it possible to successively explore different planes and thus to apprehend the doses likely to be deposited in a volume.
- the purpose of the ionizing radiation diffuser, associated with the scintillator plate, is to simulate the diffusion of radiation by the environment of a given target. More precisely, the scintillation at each point of the plate not only translates the dose received directly at this point, but also the dose received outside the plate, in the diffuser, in the vicinity of the point considered.
- the diffuser allows to simulate advantageously a tissue which is not isolated in the body of a patient.
- a diffuser block can be provided on one, but preferably on both sides of the scintillator plate.
- the thickness of the diffuser blocks can be variable depending on the importance of the diffusion phenomenon that one wishes to take into account. For scintillator plates in the dimension ranges mentioned above, it is possible to use diffuser blocks with a thickness of 150 to 400 mm, for example.
- the blocks cover all or part of the free faces of the scintillator plate.
- the scintillator material and the material of the, or diffusing blocks are preferably materials which have radiation absorption coefficients close to those of living tissue.
- the diffuser blocks are, for example, blocks of plastic material such as PMMA (Plexiglass), polyvinyltoluene or a transparent plastic material loaded with titanium oxide for example.
- the scintillating material plate is, for example in a material such as the BC 30 of the BICRON brand.
- the means for forming an image may comprise one or more cameras, and in particular CCD type cameras. The output signal from the cameras can be used for calculating doses as a function of the light intensity in different parts of the image.
- At least one diffuser block can be made of a transparent material. The light can then propagate freely through the block to the camera.
- the diffuser unit can also be provided with a mirror for returning light to the camera when the latter is not arranged in its extension.
- the transparent diffuser block subjected to the ionizing beam can give rise, according to the energy of the beam, to a stray light also called Cerenkov light.
- Cerenkov light is due to relativistic electrons of the ionizing beam which propagate in matter with a speed higher than that of the propagation of light in matter. This phenomenon takes place in a fairly marginal way in the scintillator, and more significantly in the diffuser blocks, in particular because of their greater thickness. Stray Cerenkov light is added to that of scintillation and is likely to distort the calculation of the radiation doses deposited by the ionizing beam.
- the device of the invention can be provided with different means of discrimination between the Cerenkov light and the scintillation light.
- the evaluation of the Cerenkov light contribution can subsequently be taken into account for the calculation of the radiation doses received by the scintillator.
- the discrimination means include, for example, a shutter disposed between the diffuser block and the scintillator.
- the shutter is chosen to be opaque to a light capable of being emitted by the scintillator and transparent to an ionizing beam capable of being inspected.
- two images of the scintillator can be captured through the transparent diffuser block.
- a first image, with an open shutter includes a scintillation light component and a Cerenkov light component.
- a second image carried out with closed shutter, comprises only the Cerenkov component.
- the Cerenkov component can thus be eliminated from the first image by subtracting there, point by point, the light values from the second image. This operation can take place in a digital computer.
- the shutter can be summarized as a simple cover obscuring a small part of the scintillator.
- the Cerenkov component is then calculated for the entire image from a fraction of the image corresponding to the location of the cache.
- the shutter can be a liquid crystal shutter and electrically controlled.
- the electric control causes the liquid crystal to go from a transparent state to the scintillation light to an opaque state to the scintillation light, and vice versa.
- the means of discrimination between the light of Cerenkov and the scintillation light may also comprise at least a second means for forming an image of the inspection head having a sensitivity to scintillation light and / or to Cerenkov light different from that of the first means of forming an image . Calculation means can then be provided to establish a contribution of Cerenkov light and / or scintillation light by confronting images from the first and second image forming means.
- the first and second image forming means may comprise two or more cameras associated respectively with spectral filters of different colors.
- the spectral filters then allow only selected spectral bands of light from the inspection head to pass to the cameras.
- Each camera then constitutes a means of forming a different image.
- the first and second means for forming an image can also comprise a single camera associated with a mechanism making it possible to arrange successively in the path of the light two or more different spectral filters.
- the single camera, associated with each of the different filters is considered, each time, as a different means of forming an image.
- Filters allow you to capture multiple images in different light spectra. Filters can also be optionally assigned to several parts of the field of the same image captured by the camera.
- the intensity I ⁇ of the light of wavelength ⁇ received at a point of the image can be broken down as follows:
- I ⁇ a x S + b x C
- S is a contribution of scintillation light and C the contribution due to the Cerenkov effect.
- the parameters a and b are proportionality coefficients which connect C and S respectively to a scintillation light and a Cerenkov light produced.
- the parameters a and b can be determined experimentally, using, for example, an ionization beam of known characteristics.
- the parameter “a” can be determined in such a way that S directly represents the dose of radiation received locally by the scintillator.
- the parameters a lt a 2 , bi and b 2 are of the same type as the parameters a and b mentioned above.
- the radiation dose received which contributed to the formation of the scintillation light can be put in the following form:
- a greater number of color filters makes it possible to establish other equations for determining the dose of radiation received at each point of the scintillator.
- the intensities I ⁇ are those of a point or a reduced zone of the image and correspond to a point or a corresponding zone of the scintillator.
- these can include a polarizer arranged between the scintillator and a transparent diffuser block seen by at least one image forming means. .
- One or more analyzers are then associated with the means for forming an image.
- the operation of these means of discrimination is based on the particularity of the Cerenkov light and scintillation light not to be polarized. This essentially results from the statistical character of the phenomena at the origin of these lights.
- the scintillation light is selectively polarized.
- the image forming means analyzer more or less affects the intensity of the scintillation light, depending on its orientation, but does not affect the Cerenkov light.
- the contribution of the Cerenkov effect can then be evaluated, for example, by extinguishing the scintillation light. Cerenkov's contribution can then be subtracted from total light, when the analyzer is perpendicular to its extinction position, to determine the scintillation component.
- the analyzer can also be mounted rotating between the diffuser block and the means for forming an image. It is also possible to use image forming means in the form of two or more cameras equipped with two or more crossed polarizers which respectively provide two or more images of the scintillator and of the diffuser block.
- the scintillation light, and therefore the dose D received in a given area of the scintillator, is then of the following form:
- a and b are always parameters capable of being calculated or directly established experimentally from beams of known characteristics and I_ > and If are the light intensities of the zone considered given by the cameras equipped with the polarizers (analyzers) crossed.
- the expression corresponds to a configuration using only two separate analyzers. A greater number of analyzers can be implemented. It should be noted that the multiple cameras can be replaced by a single camera which alternately receives the light from the inspection head through different analyzers, with cross orientation. Different parts of the camera field can also receive light from different analyzers simultaneously. Finally, a single rotating analyzer makes it possible to obtain different and crossed analysis orientations at different times. It thus replaces a plurality of analyzers. A number of additional improvements can be envisaged. For example, a reflector can be arranged on a main face of the scintillator which is opposite to a face carrying the transparent diffuser block, that is to say opposite to the face facing the image-forming means.
- the inspection head may include a mirror for returning the scintillation light to the image-forming means.
- a first advantage is to favor the sheltering of the imaging means of the beams ionizers to inspect.
- Another advantage may be to limit a movement relative to the inspection head alone without involving the means for forming an image.
- the deflection mirror can be arranged so as to return the light to a camera placed in the axis of rotation .
- An inspection device as described is able to deliver relative values of radiation dose supplied by a beam to be inspected. It is also possible to create an absolute measurement dosimeter by equipping the device with one or more ionization calibration chambers. These, of small size, can be accommodated in the scintillator or in the immediate vicinity of this one. Calibration takes place, for example, by adjusting the radiation dose values determined from the scintillator image for one or more zones corresponding to the locations of the calibration chambers, to the dose values determined by the calibration chambers themselves. -Same.
- Accurate calibration for establishing Cerenkov light can also take place using a scintillator with one or possibly several dead zones.
- the term “dead zones” is understood to mean zones which do not emit scintillation light, but which are capable of emitting Cerenkov light under the influence of an ionizing beam. It is, for example, a cavity formed in the scintillator plate and filled with a plastic material transparent with light absorption properties close to that of the scintillator material.
- the image of the dead zone, devoid of the scintillation component, makes it possible to directly account for the parasitic influence of Cerenkov light.
- the scintillator can comprise two or more of two scintillating material plates having absorption coefficients with different energy dependencies. Means for forming an image selectively sensitive to each of the plates are then provided.
- scintillating materials are used having absorption coefficients proportional to those of fabrics to be irradiated. Proportionality is however not necessarily perfect for the entire energy spectrum of a beam to be inspected. Thus, corrections can be made to the multiplying coefficients which relate the intensity of a recorded scintillation light to a dose that a tissue would actually receive.
- the dose D can actually be calculated according to linear terms and quadratic terms with an expression of the following form: i ij
- ki and kij are coefficients of proportionality respectively to linear and quadratic components and Si and S j represent the scintillation contributions of the different scintillator plates.
- the coefficients can be established by calibration.
- the contributions of the different scintillator plates can be distinguished by forming images of the different plates on separate cameras or by using scintillators emitting scintillation lights in offset spectra.
- the distinction can be made with spectral filters arranged in front of one or more cameras.
- the use of spectral filters is similar to that already described for the discrimination of Cerenkov light and is therefore not repeated here.
- the device of the invention can be used in a dosimeter.
- the dosimeter then further comprises a calculating unit, for establishing from the images supplied by the device, data for the distribution of a dose of radiation supplied by a beam.
- the radiation dose received for different areas of a plane or volume is calculated as a function of the scintillation light recorded for this area.
- the beam inspection device can also be integrated into radiotherapy equipment which also includes one or more sources of radiation.
- the inspection device can be adapted to the inspection of different types of beams from different types of sources.
- the device may incidentally include a diffuser block with housings for a radiation source, the block having at least one face adaptable to the inspection head.
- a diffuser block with housings for a radiation source, the block having at least one face adaptable to the inspection head.
- Such a block can be used for the inspection of beams emitted by a radiation source capable of being buried in the body of a patient.
- the invention also relates to a method of inspecting a source by means of a device as described above, in which at least one image of the scintillator is formed, and it is calculated as a function of different parts of the image local doses of radiation received by the scintillator.
- a method of inspecting a source by means of a device as described above in which at least one image of the scintillator is formed, and it is calculated as a function of different parts of the image local doses of radiation received by the scintillator.
- FIG. 1 is a simplified schematic representation of a radiotherapy device using an inspection device according to the invention.
- FIG. 2 is a graph expressing, as a function of the wavelength, the intensity of a scintillation light and a Cerenkov stray light.
- the graph is in free scale.
- FIGS 3, 4, 5 and 6 are simplified schematic representations of inspection devices according to the invention, equipped with different means of discrimination between a scintillation light and a parasitic Cerenkov light.
- FIG. 7 is a schematic and simplified representation of an improved inspection device, according to the invention.
- FIG. 1 shows a radiotherapy device comprising a beam source 10, a beam inspection device 100 and a calculation unit 12 intended to establish a beam mapping.
- the mapping aims to determine the dose of radiation that the beam is likely to deposit at any point on the body of a patient.
- the patient is modeled by an inspection head 110 of the inspection device.
- the latter is mounted on an actuator 112 capable of moving the head in order to cover the entire field intercepted by the beam.
- the actuator can be designed for translational movements in one or more directions, and possibly rotational movements. Although it can also be moved, it is considered, in the example illustrated, that the source 10 is fixed.
- the inspection head 110 comprises a scintillator in the form of a thin plate of scintillating material 114, that is to say a thin plate of material capable of converting ionizing radiation into light radiation. It is, for example, a plate of the type BC 400 of the Bicron brand. For reasons of clarity, the thickness of the plate is greatly exaggerated in the figures.
- the material plate is flanked on its main faces by two transparent diffuser blocks 116 and 117.
- a charge coupled camera (CCD) 118 which is an image forming means.
- the camera provides images in the form of a data signal directed to the calculation unit 12.
- the calculation unit which optionally also controls the movement of the inspection head, makes it possible to calculate the characteristics of the beam and in particular the doses of radiation that the latter is likely to deposit in different parts of an exposed body.
- the reference 120 summarily designates an objective which makes it possible to train on the camera an image of the scintillator plate and diffusion blocks.
- the light capable of being emitted by the scintillator 114 passes through the diffuser block 116 before reaching the camera.
- a mirror 122 indicated in broken lines can equip one of the diffusing blocks 116 so as to return all or part of the scintillation light and Cerenkov light to a second camera 119. This is also associated with a lens, not shown .
- Reference 125 briefly indicates a beam detector which makes it possible to detect the presence or absence of a beam. It is for example a rudimentary silicon detector.
- the detector 125 can advantageously be used when the beam source 10 is a pulsed source. It indeed makes it possible to synchronize the capture of the images by the calculation unit on the pulses of the beam and thus to avoid parasitic influences in the absence of beam.
- the device may include an additional diffuser block, identified with the reference 111.
- This block is provided with a housing 113 for receiving such a source. It also has a face that fits onto the inspection head.
- the shape of the block 111 shown is parallelepiped. More complex shapes, representative of the organs to be irradiated, can however be provided.
- FIG. 2 shows the shape of the distribution, as a function of the wavelength, of the intensity of the light received at a point in the image formed by the camera.
- the light includes a scintillation light component and a stray light component, called Cerenkov, already widely mentioned.
- the light received comprises a decreasing background C with wavelength.
- a relatively narrow peak S corresponding to the scintillation light. It is impossible to know directly the intensity of the scintillation, and therefore the dose of radiation received, because to the scintillation peak is added a background of Cerenkov light. For certain wavelengths at least, this background is too important to be overlooked.
- FIG. 3 shows an inspection head which comprises, between the scintillator plate 114 and the diffuser block 116 facing the camera 118, a shutter 130.
- a shutter 130 In this example, it is a liquid crystal shutter.
- the state of transparency of the shutter in the scintillation light is controlled by an electrical control device or possibly by the calculation unit 12 mentioned in relationship to Figure 1.
- the shutter is always transparent to the ionizing beam.
- the camera forms an image of Cerenkov light.
- the shutter 130 is open, the image includes the Cerenkov light and the scintillation light. The difference between the two images allows us to find the contribution of scintillation light alone.
- the Cerenkov light produced in the scintillator plate is negligible compared to that produced in the diffuser blocks.
- This approximation is valid insofar as the thickness of the scintillator plate is small compared to that of the diffuser blocks.
- the diffuser block 117, opposite the camera 118, is shown in broken lines to signify that it can possibly be eliminated.
- FIG. 4 shows a camera 118 associated with a set 142 of spectral filters which only allow narrow lines of light to pass.
- the capture of several images, through different filters 140 of this game, also makes it possible to calculate the quantity of scintillation light and therefore the dose of radiation received by the scintillator. The principle of calculation has already been explained and is not repeated here.
- the images captured through the various filters 140 can be taken successively, for example by moving in front of the camera 118 the set of filters 142. Images can also be captured simultaneously by means of a second camera 119 equipped with a second filter 142 different from a filter 140 associated with the first camera 118. In the example illustrated, the second camera receives part of the light through a semi-transparent reflecting mirror 122.
- Figure 5 shows an alternative embodiment of the inspection head, it comprises an opaque mirror 150 disposed between the scintillator plate 114 and one of the diffuser blocks 117.
- the mirror 150 has two functions. The first function is that of reflector. The mirror 150 in fact makes it possible to return a greater part of the scintillation light to a first camera 118. This camera 118 therefore receives the scintillation light and the Cerenkov light created in one of the transparent diffusing blocks 116.
- the mirror can also incidentally have a second function. It is a screen function to prevent the scintillation light from reaching a second camera 119 arranged opposite the second transparent diffuser block 117.
- the second camera thus receives only a Cerenkov light created in the second diffuser block 117. From the Cerenkov light received by the second camera 119, and taking into account the characteristics of the diffusers 116, 117, it is possible to evaluate by analogy the contribution of Cerenkov light in the image formed by the first camera 118. This contribution can then be subtracted by calculation from the image of the first camera
- FIG. 6 shows yet another embodiment in which a polarizer 160 is disposed between the scintillator plate 114 and a first diffuser block 116.
- the polarizer makes it possible to polarize the initially isotropic scintillation light.
- the v Cerenkov light appearing in the diffuser block 116 facing the camera is however not polarized.
- Discrimination is then carried out between the two light contributions by means of an analyzer 162 positioned between the first diffuser block 116 and the camera 118.
- the analyzer can be fixed and / or rotating and makes it possible to extinguish all or part of the light scintillation. This extinction does not affect the Cerenkov light which is not polarized.
- the single camera with an analyzer can be replaced by a set of two cameras 118, 119 associated with two crossed analyzers 162, 163.
- the second diffuser block 117 if present, is isolated from the scintillator 114 by a material opaque to Cerenkov light.
- FIG. 7 shows a particular embodiment of the inspection head 110, in which the latter comprises two scintillator plates 114, 115.
- the two plates are placed side by side or optionally separated by a mask opaque to scintillation light or a mirror.
- the scintillation light from the two plates is captured by two cameras 118, 119. It passes respectively through two transparent diffusers 116, 117 attached to the main faces of the plates.
- the two scintillator plates 114, 115 emit scintillation lights in offset spectra, their light can be captured by a single camera associated with selective spectral filters.
- the images provided by the two cameras, or possibly by the single camera, are used to locally calculate the radiation doses received as a function of a weighted contribution from each of the scintillators.
- the weighting can be linear and / or quadratic.
- Reference 170 indicates a small ionization chamber integrated in the scintillator plates, and possibly in part in the diffuser blocks. This chamber delivers a signal directed to the calculation unit 12. This signal can be compared with a dose measurement carried out from the images of the cameras, either for calibration purposes or for measurement purposes in absolute value of the dose.
- the reference 172 designates a small dead zone of the scintillator plates 114, 115.
- this dead zone gives a direct assessment of the Cerenkov contribution. This contribution can also be used for a calibration of the dosimeter. Finally, the use of a dead zone allows, if necessary, to assess the proportion (low) v of Cerenkov light produced in the thickness of the scintillator plates.
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- High Energy & Nuclear Physics (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Medical Informatics (AREA)
- Engineering & Computer Science (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Surgery (AREA)
- Optics & Photonics (AREA)
- Pathology (AREA)
- Radiology & Medical Imaging (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Biophysics (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Measurement Of Radiation (AREA)
- Radiation-Therapy Devices (AREA)
Abstract
Description
Claims
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/485,936 US7102136B2 (en) | 2002-06-03 | 2003-05-30 | Ionizing beam inspection device and process |
CA002457014A CA2457014A1 (fr) | 2002-06-03 | 2003-05-30 | Dispositif et procede d'inspection d'un faisceau ionisant |
JP2004508880A JP2005528598A (ja) | 2002-06-03 | 2003-05-30 | 電離ビーム検査装置とプロセス |
AU2003258782A AU2003258782A1 (en) | 2002-06-03 | 2003-05-30 | Device and method for inspecting an ionising beam |
BR0304923-0A BR0304923A (pt) | 2002-06-03 | 2003-05-30 | Dispositivo de inspeção de um feixe, dosìmetro e processo de inspeção de uma fonte |
EP03756034A EP1509786A2 (fr) | 2002-06-03 | 2003-05-30 | Dispositif et procede d'inspection d'un faisceau ionisant |
KR10-2004-7001475A KR20050006122A (ko) | 2002-06-03 | 2003-05-30 | 이온화 빔 검사용 장치 및 방법 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR02/06778 | 2002-06-03 | ||
FR0206778A FR2840412B1 (fr) | 2002-06-03 | 2002-06-03 | Dispositif et procede d'inspection d'un faisceau ionisant |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2003101528A2 true WO2003101528A2 (fr) | 2003-12-11 |
WO2003101528A3 WO2003101528A3 (fr) | 2004-04-01 |
Family
ID=29558912
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR2003/001639 WO2003101528A2 (fr) | 2002-06-03 | 2003-05-30 | Dispositif et procede d'inspection d'un faisceau ionisant |
Country Status (10)
Country | Link |
---|---|
US (1) | US7102136B2 (fr) |
EP (1) | EP1509786A2 (fr) |
JP (1) | JP2005528598A (fr) |
KR (1) | KR20050006122A (fr) |
CN (1) | CN1302293C (fr) |
AU (1) | AU2003258782A1 (fr) |
BR (1) | BR0304923A (fr) |
CA (1) | CA2457014A1 (fr) |
FR (1) | FR2840412B1 (fr) |
WO (1) | WO2003101528A2 (fr) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103984002A (zh) * | 2014-04-28 | 2014-08-13 | 中国工程物理研究院流体物理研究所 | 含混合离子束流的h+离子截面信号采集系统和方法 |
EP2853926A3 (fr) * | 2013-09-30 | 2015-04-22 | Kabushiki Kaisha Toshiba | Capteur et procédé de détection de radiation |
CN111212679A (zh) * | 2017-10-11 | 2020-05-29 | 希尔应用医学有限公司 | 提供离子束的系统和方法 |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1857836B1 (fr) * | 2006-05-15 | 2009-10-21 | Eldim Sa | Dispositif et procédé pour distinguer de radiation Cerenkov et des radiations scintillantes |
CN101598799B (zh) * | 2008-06-05 | 2012-07-11 | 清华大学 | 一种切伦科夫探测器及利用其进行检测的方法 |
WO2010078034A2 (fr) * | 2008-12-17 | 2010-07-08 | Saint-Gobain Ceramics & Plastics, Inc. | Procédé et appareil de réseau de scintillation |
US8481952B2 (en) * | 2008-12-23 | 2013-07-09 | Saint-Gobain Ceramics & Plastics, Inc. | Scintillation separator |
JP5422272B2 (ja) * | 2009-06-25 | 2014-02-19 | 株式会社東芝 | 核医学診断装置、及び、核医学診断装置における検出器の故障特定方法 |
WO2011005862A2 (fr) * | 2009-07-07 | 2011-01-13 | The Board Of Regents Of The University Of Texas System | Scintillateur liquide pour dosimétrie en 3d pour modalités de radiothérapie |
KR101328478B1 (ko) * | 2012-07-26 | 2013-11-13 | 포항공과대학교 산학협력단 | 엑스선 영상 검출기용 광변환장치 및 이를 구비한 엑스선 영상 검출기 |
CA2908092A1 (fr) * | 2013-03-28 | 2014-10-02 | Atomic Energy Of Canada Limited / Energie Atomique Du Canada Limitee | Systeme et procede pour la dosimetrie tridimensionnelle en temps reel |
CN107923986A (zh) | 2015-09-14 | 2018-04-17 | 哈里伯顿能源服务公司 | 用于井下核应用的闪烁体检测器中的暗电流校正 |
WO2020124266A1 (fr) * | 2018-12-21 | 2020-06-25 | The Royal Institution For The Advancement Of Learning/Mcgill University | Dosimètre de rayonnement |
CA3179483A1 (fr) * | 2020-05-21 | 2021-11-25 | Airanswers, Inc. | Detection du radon avec chambre de diffusion en trois parties et revetement de scintillation sur une surface etendue |
CN113406686A (zh) * | 2021-06-16 | 2021-09-17 | 中国科学院近代物理研究所 | 一种离子束三维剂量分布探测装置及方法 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5905263A (en) * | 1996-11-26 | 1999-05-18 | Mitsubishi Denki Kabushiki Kaisha | Depth dose measuring device |
US6225622B1 (en) * | 1998-07-31 | 2001-05-01 | Daniel Navarro | Dynamic radiation scanning device |
JP2001346894A (ja) * | 2000-06-08 | 2001-12-18 | Mitsubishi Electric Corp | 線量分布測定装置 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5580075A (en) * | 1978-12-12 | 1980-06-16 | Mitsubishi Electric Corp | Radiation energy monitor |
JP3263154B2 (ja) * | 1992-11-18 | 2002-03-04 | 株式会社東芝 | インライン中性子モニタの計数率評価法 |
JP3102342B2 (ja) * | 1996-02-27 | 2000-10-23 | 三菱電機株式会社 | 深部線量測定装置 |
JP3841898B2 (ja) * | 1996-11-21 | 2006-11-08 | 三菱電機株式会社 | 深部線量測定装置 |
JP3413084B2 (ja) * | 1997-11-20 | 2003-06-03 | キヤノン株式会社 | 放射線撮像装置及び撮像方法 |
US6518580B1 (en) * | 1998-11-16 | 2003-02-11 | The United States Of America As Represented By The United States Department Of Energy | Proton radiography based on near-threshold Cerenkov radiation |
JP2001056381A (ja) * | 1999-08-20 | 2001-02-27 | Mitsubishi Electric Corp | 局所線量計及びそれを用いた医療装置 |
JP4115675B2 (ja) * | 2001-03-14 | 2008-07-09 | 三菱電機株式会社 | 強度変調療法用吸収線量測定装置 |
FR2822239B1 (fr) * | 2001-03-15 | 2003-09-26 | Centre Nat Rech Scient | Procede de mesure de dose d'irradiation |
JP4146648B2 (ja) * | 2002-02-14 | 2008-09-10 | 三菱電機株式会社 | 吸収線量分布測定装置 |
-
2002
- 2002-06-03 FR FR0206778A patent/FR2840412B1/fr not_active Expired - Fee Related
-
2003
- 2003-05-30 KR KR10-2004-7001475A patent/KR20050006122A/ko not_active Application Discontinuation
- 2003-05-30 BR BR0304923-0A patent/BR0304923A/pt not_active Application Discontinuation
- 2003-05-30 CA CA002457014A patent/CA2457014A1/fr not_active Abandoned
- 2003-05-30 US US10/485,936 patent/US7102136B2/en not_active Expired - Fee Related
- 2003-05-30 JP JP2004508880A patent/JP2005528598A/ja active Pending
- 2003-05-30 WO PCT/FR2003/001639 patent/WO2003101528A2/fr active Application Filing
- 2003-05-30 AU AU2003258782A patent/AU2003258782A1/en not_active Abandoned
- 2003-05-30 EP EP03756034A patent/EP1509786A2/fr not_active Withdrawn
- 2003-05-30 CN CNB038007819A patent/CN1302293C/zh not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5905263A (en) * | 1996-11-26 | 1999-05-18 | Mitsubishi Denki Kabushiki Kaisha | Depth dose measuring device |
US6225622B1 (en) * | 1998-07-31 | 2001-05-01 | Daniel Navarro | Dynamic radiation scanning device |
JP2001346894A (ja) * | 2000-06-08 | 2001-12-18 | Mitsubishi Electric Corp | 線量分布測定装置 |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 2002, no. 04, 4 août 2002 (2002-08-04) & JP 2001 346894 A (MITSUBISHI ELECTRIC CORP), 18 décembre 2001 (2001-12-18) * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2853926A3 (fr) * | 2013-09-30 | 2015-04-22 | Kabushiki Kaisha Toshiba | Capteur et procédé de détection de radiation |
US9927536B2 (en) | 2013-09-30 | 2018-03-27 | Kabushiki Kaisha Toshiba | Radiation detection apparatus and radiation detection method |
CN103984002A (zh) * | 2014-04-28 | 2014-08-13 | 中国工程物理研究院流体物理研究所 | 含混合离子束流的h+离子截面信号采集系统和方法 |
CN111212679A (zh) * | 2017-10-11 | 2020-05-29 | 希尔应用医学有限公司 | 提供离子束的系统和方法 |
Also Published As
Publication number | Publication date |
---|---|
EP1509786A2 (fr) | 2005-03-02 |
FR2840412A1 (fr) | 2003-12-05 |
CN1302293C (zh) | 2007-02-28 |
WO2003101528A3 (fr) | 2004-04-01 |
AU2003258782A8 (en) | 2003-12-19 |
US7102136B2 (en) | 2006-09-05 |
AU2003258782A1 (en) | 2003-12-19 |
CN1543576A (zh) | 2004-11-03 |
BR0304923A (pt) | 2004-12-28 |
US20040178361A1 (en) | 2004-09-16 |
CA2457014A1 (fr) | 2003-12-11 |
FR2840412B1 (fr) | 2005-02-25 |
JP2005528598A (ja) | 2005-09-22 |
KR20050006122A (ko) | 2005-01-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2003101528A2 (fr) | Dispositif et procede d'inspection d'un faisceau ionisant | |
EP1004039B1 (fr) | Procede et systeme d'imagerie radiographique utilisant des faisceaux de rayons gammas et rayons x | |
EP0810631B1 (fr) | Dispositif d'imagerie radiographique à haute résolution | |
FR2668612A1 (fr) | Dispositif d'imagerie de radiations ionisantes. | |
EP2288939B1 (fr) | Dispositif d'imagerie gamma ameliore permettant la localisation precise de sources irradiantes dans l'espace | |
EP2035861B1 (fr) | Dispositif de localisation et d'imagerie de sources de rayonnement gamma ou x. | |
FR2471178A1 (fr) | Appareil de radiographie | |
Marrs et al. | System for calibrating the energy-dependent response of an elliptical Bragg-crystal spectrometer | |
FR2704655A1 (fr) | Mini-caméra pour la détection rapprochée d'un rayonnement nucléaire émis par un radio-isotope et application à l'assistance chirurgicale. | |
EP2145208B1 (fr) | Dispositif d'imagerie par rayons x à source poly-chromatique | |
Kirkwood et al. | Imaging backscattered and near to backscattered light in ignition scale plasmas | |
FR3022029A1 (fr) | Dispositif d'analyse spectroscopique de carottes de forage | |
FR3079311A1 (fr) | Detecteur scintillateur multicouche et procede de reconstruction d'une distribution spatiale d'un faisceau d'irradiation | |
FR3079310A1 (fr) | Dispositif de mesure de rayonnements alpha et/ou beta provenant d'une surface solide | |
FR2738669A1 (fr) | Tube generateur de neutrons equipe d'un detecteur de particules alpha | |
CN111443101A (zh) | 一种用于不同晶体x射线衍射效率的直接比对系统 | |
FR2967495A1 (fr) | Dispositif d'imagerie de fluorescence x | |
CH691006A5 (fr) | Procédé, détecteur et dispositif d'imagerie radiographique utilisant des faisceaux de rayons gamma et rayon X appliqués au traitement radiothérapique et au contrôle non-destructif. | |
Fuqua et al. | Out of band scatter measurements from OLI optical bandpass filters | |
WO2020157263A1 (fr) | Procedes et systemes pour l'imagerie de contraste phase | |
Wang et al. | A novel design for 100 meter-scale water attenuation length measurement and monitoring | |
Mortensen | Thickness dependence of electron transport in amorphous selenium for use in direct conversion flat panel X-ray detectors | |
WO2022263739A1 (fr) | Procédé de mesure optique de dosimétrie et dispositif de mesure optique de dosimétrie | |
Goldin et al. | Bismuth Germanate (BGO) array for spectroscopy of gamma pulse | |
Vadawale et al. | Prospects of hard X-ray polarimetry with Astrosat-CZTI |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NI NO NZ OM PH PL PT RO RU SC SD SE SG SK SL TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2003756034 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 55/MUMNP/2004 Country of ref document: IN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 10485936 Country of ref document: US Ref document number: 2457014 Country of ref document: CA Ref document number: 1020047001475 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 20038007819 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2004508880 Country of ref document: JP |
|
WWP | Wipo information: published in national office |
Ref document number: 2003756034 Country of ref document: EP |