CN104337540A - X-ray unit with slit aperture - Google Patents
X-ray unit with slit aperture Download PDFInfo
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- CN104337540A CN104337540A CN201410371675.7A CN201410371675A CN104337540A CN 104337540 A CN104337540 A CN 104337540A CN 201410371675 A CN201410371675 A CN 201410371675A CN 104337540 A CN104337540 A CN 104337540A
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
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- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
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- G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
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- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
- A61B6/5205—Devices using data or image processing specially adapted for radiation diagnosis involving processing of raw data to produce diagnostic data
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- 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
- A61B6/40—Arrangements for generating radiation specially adapted for radiation diagnosis
- A61B6/405—Source units specially adapted to modify characteristics of the beam during the data acquisition process
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Abstract
The present invention includes an X-ray unit with a slit aperture. The X-ray unit of the present invention is designed to move a detection object at a feeding speed along a vertical shaft. The X-ray unit may also include a recording unit which is allowed to rotate around the vertical shaft. The recording unit comprises an X-ray emitter for emitting X-ray beams and an X-ray detector for detecting X-ray. Selective irradiation on effective area is achieved in a spiral mode by employing a first slit aperture, which is provided with a first opening that is along the vertical shaft and has a width of D_1, used for generating X-ray beam at the vertical shaft with a width of DZ_1, and fixedly positioned; and a second slit aperture which is provided with a second opening that is along the vertical shaft and has a width of D_2, used for generating X-ray beam at the vertical shaft with a width of DZ_2, and fixedly positioned; wherein DZ_2< DZ_1.
Description
Technical field
The present invention relates to a kind of x-ray unit and a kind of method for recording X-ray projection.
Background technology
Computer tomography is a kind of formation method, and it is mainly used in medical diagnosis and for material tests.In order to record the radioscopic image of fault imaging, X-ray emitter and X-ray detector coefficient with it rotate around check object.In helicon mode, check object moves along rotating shaft, records X-ray projection under different angle positions simultaneously.After have recorded the projection of the X-ray under helicon mode, process the projection of this X-ray, thus produce the radioscopic image of three-dimensional fault imaging.The region of the check object that should rebuild is also referred to as effective volume.The record of the X-ray projection under helicon mode is also referred to as helical scanning.
In order to the radioscopic image of reconstruction tomography, the X-ray projection group recorded during helical scanning must be complete.If only should from the limited effective volume in check object the radioscopic image of reconstruction tomography, then need rear scanning (Nachlauf) or prescan (Vorlauf), wherein usually also scan the region outside effective volume.Due to nowadays X-ray detector usually large width and need this rear scanning or prescan.Bring thus for the unnecessary radiation burden outside check object effective volume.This has problem when check object is patient at medical domain especially.Along with the width of Modern X-ray detector or the increase of line number, this problem becomes more serious.A kind of probability avoiding the unnecessary radiation caused due to rear scanning or prescan in helical scanning to bear is, by aperture shaping X-ray, makes in fact only to irradiate effective volume.
Known a kind of diaphragm apparatus from DE 10 2,005 018 811 A1, the X-ray apparatus that it is arranged for the scanning for object, there are at least two apertures, wherein, for at least one Scanning Section, the radiant flux utilizing the first aperture to regulate dynamically can be covered at least in part by the second aperture.In addition, known from described open file, remaining radiant flux only irradiates the region of the contributive object of reconstruction for image.In addition, aperture can be gap aperture.
Summary of the invention
The technical problem to be solved in the present invention is, the technology by aperture is simply arranged and remained very little by the radiation burden caused due to rear scanning or prescan in the record of the fault imaging of helicon mode.
This technical problem is by being solved according to x-ray unit of the present invention and according to method of the present invention.
The following describe about claimed equipment and about claimed method technical problem according to solution of the present invention.Feature, advantage or alternate embodiments equally also can be converted to other claimed content as mentioned herein, and vice versa.In other words, such as also can be extended to for the device claim of equipment and there is associated methods describe or claimed feature.At this, constructed the functional character of corresponding method by corresponding apparatus module.
The present invention includes a kind of x-ray unit and a kind of method for recording X-ray projection.X-ray unit according to the present invention is designed to move check object along the longitudinal axis with feed speed, and comprises the record cell that can rotate around the longitudinal axis.Record cell comprises the X-ray emitter for the X-ray of emitting x-ray form and the X-ray detector for detecting x-ray.Inventor recognizes, the width had along the longitudinal axis be first opening of D_1, be designed to be formed in longitudinal axis horizontal
have the X-ray beam of width D Z_1, the first gap aperture of stationary positioned and the width had along the longitudinal axis be second opening of D_2, be designed to be formed in the second gap aperture that longitudinal axis horizontal has an X-ray beam of width D Z_2 and be enough to realize the elective irradiation to effective volume under helicon mode, wherein have DZ_2<DZ_1.Because only the second gap aperture is moved along the longitudinal axis according to feed speed according to the present invention, make the X-ray that is shaped by gap aperture only examination object to the contributive region of the radioscopic image of reconstruction tomography, so the radiation burden caused due to rear scanning or prescan in the record of the fault imaging of helicon mode remains very little.
The aperture advised is arranged in and technically especially easily realizes, because need only arrange single aperture movably.In addition, aperture is gap aperture according to the present invention, thus as a whole aperture need only be made to move, instead of the various piece of mobile aperture or even multiple aperture are relative to moving mutually.In addition, gap aperture can easily and manufacture at low cost relative to the aperture with multiple moveable part.In addition, the displacement of gap aperture becomes relatively simple, thus the aperture with the opening of different in width can be used to according to method of the present invention.The present invention's therefore simple, low cost of technology and flexibly.
According to another aspect of the present invention, check object is in helicon mode, move with the first feed speed during prescan, and move with the second feed speed in rear scan period, wherein during rear scanning and prescan, move the second gap aperture as follows respectively, the X-ray beam be shaped by gap aperture is moved along the longitudinal axis with the speed identical with check object respectively.
According to another aspect of the present invention, based on the reconstruction carrying out the radioscopic image of fault imaging according to the projection of the X-ray of record of the present invention, wherein, described reconstruction is comprised and being weighted according to the intensity of the X-ray be shaped by gap aperture.Because due to only mobile second gap aperture the fact of stationary positioned first gap aperture, the irradiation causing the X-ray detector of the almost each time point for prescan or rear scanning is asymmetric.If read detector element during helical scanning, then must consider unsymmetry when rebuilding by weighting.Complete reading detector and being weighted in subsequently technically easily realize.
According to another aspect of the present invention, be weighted when rebuilding binary system.Which especially easily realizes.
According to another aspect of the present invention, be weighted pro rata with the intensity of the X-ray be shaped by gap aperture.Which is accurate especially, because have also contemplated that part is covered.Particularly when particularly rapidly moving the second gap aperture, which has advantage.
According to another aspect of the present invention, described reconstruction is the filtered back projection of weighting.Algorithm for reconstructing based on filtered back projection provides the advantage of relatively short running time and relative few computing cost.
According to another aspect of the present invention, described reconstruction is the reconstruction of the iteration by statistics weighting.The algorithm for reconstructing of iteration provides high-resolution (particularly in edge) and not easily goes out the advantage of artifact.
Accompanying drawing explanation
Describe in detail by embodiment illustrated in the accompanying drawings below and explain the present invention.Wherein:
Fig. 1 show with computer tomography instrument form according to x-ray unit of the present invention,
Fig. 2 shows the cross section arranged according to gap of the present invention aperture,
Fig. 3 show in graphical form two gap apertures relative to frame during the record of helicon mode according to position of the present invention, and
Fig. 4 show in graphical form two gap apertures relative to check object during the record of helicon mode according to position of the present invention.
Detailed description of the invention
Fig. 1 show with computer tomography instrument form according to x-ray unit of the present invention, it has record cell, and this record cell comprises X-ray emitter 8 and X-ray detector 9.Record cell rotates around the longitudinal axis 5 during the projection of record X-ray, and the X-ray of X-ray emitter 8 emitting x-ray form during recording.X-ray beam particularly can be shaped fan-shaped or taper.Computer tomography instrument also can have more than only one X-ray emitter 8 and more than the only X-ray detector 9 of, to realize the record according to so-called dual energy method.In example shown here, X-ray emitter 8 is X-ray tubes.In example shown here, X-ray detector 9 is the row detectors with multiple row, such as, have 128 row or have 256 row.But X-ray detector 9 also can be configured to planar detector.X-ray detector 9 is usually configured to scintillation counter, its lower energy photon sigmatron photon conversion become in spectrum by flasher, and detects by photodiode subsequently.Alternatively X-ray detector 9 can be configured to the detector of directly conversion, it is directly making full use of by inner light stimulus the signal stream under photovoltaic principle, sigmatron photon conversion being become electricity by semi-conducting material.
When recording X-ray projection, patient 3 lies on patient table 6, and patient table is connected with bed pedestal 14, makes bed pedestal carry the patient table 6 with patient 3.Patient table 6 is designed to move the opening 10 of patient through record cell along record direction with feed speed.Record direction is provided by the longitudinal axis 5 usually, and this longitudinal axis is also the rotating shaft of record cell.But the longitudinal axis 5 can relative record direction (moving patient 3 along this record direction during recording) be also tilt, such as, by record cell being configured to the part of tiltable frame.
Record X-ray projection from different directions by rotating record cell, it can be reconstructed into data set that is high-resolution, space three-dimensional.Carry out record according to the present invention according to helicon mode, wherein move patient 3 continuously along the longitudinal axis 5.As shown in Figure 3, be divided into three phases according to the record of helicon mode, i.e. the scanning of prescan, effective volume and rear scanning.In order to avoid during rear scanning or prescan to the unnecessary irradiation of patient 3, the parts of two gap apertures as record cell arranged according to the present invention.Gap aperture is both positioned at 8 sides of the eye point of the direct contiguous X-ray of X-ray emitter.Two gap apertures are all designed for be shaped by absorption of x-rays X-ray or X-ray beam.Therefore, gap aperture is made up of the material of horizontal absorption X-ray, and this material such as can comprise tungsten, molybdenum, ferrum and other metal.
According to the present invention, the first gap aperture 15 is fixed positioned in record cell, and the second gap aperture 16 can move along the longitudinal axis 5 according to the feed speed of patient 3.The movement of the second gap aperture 16 can pass through executor, such as motor realizes.Therefore, record cell only has executor that is unique, such as motor form in an embodiment of the invention, for mobile gap aperture, makes the present invention become the simple also low cost of technology thus.
In example shown here, computer tomography instrument also comprises computer 12, and it is such as designed to computer for controlling tomograph and projects for the X-ray that Storage and Processing is a large amount of.Computer 12 is connected with the output unit 11 of the radioscopic image such as exporting fault imaging for image.Output unit 11 is such as one or more LCD, plasma or OLED screen curtain.In addition, computer 12 is connected with input block 13.Input block 13 is such as used to as process X-ray Projection selection parameter.Input block 13 is such as keyboard, mouse, so-called touch screen or the mike for phonetic entry.Interface makes computer 12 can communicate with computed tomography imager and with input block 13 or output unit 11.Interface is generally known hardware interface or software interface, such as, be hardware interface pci bus, USB or live wire.
In yet another embodiment of the present invention, x-ray unit has reconstruction unit 4.Reconstruction unit 4 both can comprise hardware, also can comprise software.Reconstruction unit 4 such as can comprise FPGA or processor.In example shown here, reconstruction unit 4 is configured to computer program, and it can be loaded in the internal storage of computer 12.But in the embodiment substituted, reconstruction unit 4 also can be positioned on independent computer, and this computer is not designed to computer for controlling tomograph.
Fig. 2 shows the cross section arranged according to gap of the present invention aperture.That the width had along the longitudinal axis 5 is first opening of D_1, that the first gap aperture 15 of stationary positioned is designed to be formed in the longitudinal axis 5 level has the X-ray beam of width D Z_1.The width had along the longitudinal axis 5 is the X-ray beam that level that the second gap aperture 16 of second opening of D_2 is designed to be formed in the longitudinal axis 5 has width D Z_2, wherein DZ_2≤DZ_1.DZ_2<DZ_1 is had in the embodiment substituted.At this, width is measured along the longitudinal axis 5 respectively, also defines z coordinate below this longitudinal axis.By the width at the level place at the longitudinal axis 5, expression X-ray beam, goes out along the width of the longitudinal axis as shown in Figure 2 when projecting on the longitudinal axis 5.Idea of the present invention is, the radiant flux be shaped by two gap apertures is the highest can have width D Z_2.Therefore, represent at projected X-rays bundle by width D Z_1 and form by means of only the first gap aperture 15 (namely not having the effect of the second gap aperture 16 ground) with this place time width.
Strictly speaking, the width of radiant flux is relevant along the position of the longitudinal axis 5 with the second gap aperture 16.Simplifiedly, have ignored the effect of the projection distortion caused due to the different angles between X-ray and the second gap aperture 16 here.Width D Z_2 by the second radiant flux represent relative to the first gap aperture 15 the first opening medially orientation time width.Alternatively, the orientation placed in the middle relative to X-ray emitter 8 can also be represented.
In embodiment shown here, the first gap aperture 15 to the second gap aperture 16 is closer to x-ray source 8.In the embodiment substituted, the second gap aperture 16 to the first gap aperture 15 is closer to x-ray source 8.In addition, in example shown here, D_2<D_1.
The part of the absorption of x-rays radiation of the second gap aperture 16 must greatly to can by moving the opening that the second gap aperture 16 carrys out complete closure first aperture 15 along the longitudinal axis 5.In other words, second gap aperture 16 is necessarily dimensioned, arrange and removable, and the x-ray bombardment the second gap aperture 16 can being stopped completely launched by X-ray emitter 8 is to X-ray detector 9 or the check object X-ray emitter 8 and X-ray detector 9.
Gap aperture (particularly when spherical form) can have the opening of rectangle, and it is also perpendicular to extending with D_1 or with the width that D_2 represents here.Especially, the opening of the first and second gap apertures can extend perpendicular to D_1 or with the width that D_2 represents respectively as far as possible, makes it in the direction in which can X-ray irradiation detector 9 completely.In other embodiment, gap aperture is flat or cylinder form.
Be the opening of the first gap aperture 15 be sized to the X-ray that makes to be shaped by the first gap aperture 15 can whole of X-ray irradiation detector 9.In embodiment shown here, the first gap aperture 15 is fixed positioned in record cell, makes its opening also relative to X-ray detector 9 medially orientation.This is described by the first middle position 17 in fig. 2, which show the middle position of the X-ray be shaped by the first gap aperture 15.On the contrary, the second middle position 18 of the X-ray be shaped by the second gap aperture 16 is moveable, because the second gap aperture 16 is removable along the longitudinal axis 5, and has D_2<D_1 in example shown here in addition.According to the present invention, the second gap aperture 16 moves as making X-ray that produce, that be shaped by two gap apertures at the most of the time X-ray irradiation detector 9 asymmetrically of helical scanning along the longitudinal axis 5 during helical scanning.Asymmetric irradiation means, the middle position of the X-ray of generation is not placed in the middle relative to X-ray detector 9.
In other embodiment, second gap aperture 16 has the other opening of at least one width D _ 3 along the longitudinal axis 5 ≠ D_2, the level being designed to be formed in the longitudinal axis 5 has the X-ray beam of width D Z_3 ≠ DZ_2 and DZ_3≤DZ_1 or DZ_3<DZ_1.In change preferably, there is D_3≤D_1 or D_3<D_1.In this embodiment, mutual distance must far be installed by least two openings of the second gap aperture 16, make the second gap aperture 16 can stop the X-ray be shaped by the first gap aperture 15 completely.In other words, the second gap aperture 16 always must have the members of absorption of x-rays between at least two openings, and its width is enough to absorb the X-ray be shaped by the first gap aperture 15 completely.
Fig. 3 show in graphical form two gap apertures relative to frame during the record of helicon mode according to position of the present invention.At this, mark the time on the horizontal axis, represented with " t ", and marked z coordinate on a vertical axis, represented with " z ".Below the interval between t_0 and t_1 should be called dt_1, the interval between t_1 and t_2 be called dt_2, and the interval between t_2 and t_3 is called dt_3.In interval dt_1, carry out the prescan of helical scanning, scan after carrying out in interval dt_3.During rear scanning or prescan, need not in order to record fault imaging reconstruction needed for X-ray projection and X-ray irradiation detector 9 completely.More precisely, during rear scanning or prescan, the irradiation being equivalent to complete X-ray irradiation detector 9 of check object only means unnecessary radiation burden.On the contrary, in interval dt_2, can by check object irradiate for making it be equivalent to complete X-ray irradiation detector 9 because in this case only effective volume be positioned on radiation path.Rear scanning or prescan due to helicon mode but necessity, and increase along with the width of X-ray detector 9 and demonstrate mainly in the problem of medical domain, because it has the opposite effect to pursuit dose efficiency.
According to the present invention, during helical scanning, move the second gap aperture 16 according to check object or patient table 6 along the feed speed of the longitudinal axis 5, make the X-ray that is shaped by gap aperture only examination object to the contributive region of the radioscopic image of reconstruction tomography.In other words, irradiation area 20 is as shown in Figure 3 only effective volume.The referential selected there is based on the first gap aperture 15.Second gap aperture 16 moves along z direction with second speed v_B2 during scanning effective volume with First Speed v_B1 during rear scanning or prescan, and wherein, speed v _ B1 with v_B2 is relevant with the feed speed of check object.In embodiments of the present invention, move the second gap aperture 16 according to feed speed, make particularly pitch change between different time interval.In helicon mode, pitch is defined as the feeding of patient table 6 under each record cell rotational case and the ratio of detector 9 along the width of the longitudinal axis 5.
Fig. 4 show in graphical form two gap apertures relative to check object during the record of helicon mode according to position of the present invention.In chart shown here, make the relative motion that formed with the motion of feed speed due to check object between check object and the first gap aperture 15 visible.Feed speed improves in the second interval dt_2.First and the 3rd in interval by the speed of the second gap aperture 16 tolerance for making the X-ray beam be shaped by gap aperture move with corresponding feed speed.So the second gap aperture 16 is fixed about check object position in interval first and the 3rd.Only in the second interval dt_2, the speed of feed speed and X-ray beam is had any different.The movement of the second gap aperture 16 and the ratio according to the present invention of feed speed cause only irradiating effective volume 19, and during rear scanning or prescan, do not irradiate region 21a, the b outside effective volume.In the conventional method utilizing static aperture, contrary region 21a, b irradiated outside effective volume.
In an embodiment of the invention, check object moves with the first feed speed v_1 respectively in very first time interval dt_1 and the 3rd interval dt_3, and move with the second feed speed v_2>v_1 at the second interval dt_2, wherein can move the second gap aperture 16, what make X-ray detector 9 expands Breadth Maximum along the longitudinal axis 5 from minimum widith in the interim very first time by the region of x-ray bombardment, wherein, X-ray irradiates the scope of Breadth Maximum during the second interval, wherein, X-ray detector 9 during the 3rd interval, narrow down to minimum zone from maximum magnitude by the region of x-ray bombardment.
In another embodiment of the present invention, give the second feed speed by v_2=v_1 (1+ (DZ_1-DZ_2)/(L-DZ_2)), wherein L is the width of effective volume along the longitudinal axis 5.At this, the second gap aperture 16 can first and the 3rd interval move with the first aperture speed v B_1 respectively, thus make the speed of X-ray beam equal v_1.In addition, the second gap aperture 16 can move with the second aperture speed v B_2 at the second interval, thus makes the speed of X-ray beam equal (DZ_1-DZ_2)/dt_2.The speed of X-ray beam always represents the speed of the level at the longitudinal axis 5.
In another embodiment of the present invention, give this speed by following relation, wherein, give the length of effective volume along the longitudinal axis 5 by L.Patient table 6 moves, and the check object be positioned at thus on patient table 6 moves according to following speed:
-v_1, between time point t_0 and t_1=t_0+DZ_2/v_1;
-v_2=v_1 (1+ (DZ_1-DZ_2)/(L-DZ_2)), between time point t_1 and t_2=t_0+L/v_1; And
-v_1, between time point t_2 and t_3=t_0+ (L+DZ_2)/v_1.
So the second gap aperture 16 moves as making the X-ray beam be shaped by two gap apertures move along the longitudinal axis 5 according to following speed:
-v_1, between time point t_0 and t_1 and between time point t_2 and t_3; And
-(DZ_1-DZ_2)/(t_2-t_1)。
In other change of embodiment described here, the speed transition between different time interval for the speed of check object and the speed of the second gap aperture 16 is not discrete, but continuous print.
Corresponding to according to the embodiment of the present invention described, the middle position of the X-ray produced during helical scanning is changed into and to be made during the most of the time of helical scanning X-ray irradiation detector 9 asymmetrically.Thus, during the radioscopic image of reconstruction tomography, the X-ray to being shaped by X-ray detector 9 is needed to be weighted.This especially sets up when reading the detector element of X-ray detector 9 as complete X-ray irradiation detector 9.Weighting during rebuilding always relates to the weighting to X-ray, just as not having check object interference emission path.In this case, the object of weighting considers the intensity of the X-ray caused due to movement or the position of gap aperture.Therefore, calculating strength can be carried out, to use it for weighting subsequently according to the known movement of gap aperture or position.In order to calibration intensity value, can not have to perform according to helical scanning of the present invention in check object situation yet.
Be weighted according to the X-ray be shaped by gap aperture such as binary system, because such weighting especially easily realizes.Alternatively, be weighted pro rata with the intensity of the X-ray be shaped by gap aperture, because this kind of weighting is accurate especially, particularly when the second gap aperture 16 is mobile fast.The weighting proportional with the intensity of the X-ray be shaped by gap aperture have also contemplated that the effect of partly covering (Halbschatten).In other embodiment, other mathematical relationship can be followed and be weighted, such as can square ground or relevant to intensity level exponentially.
In the embodiment of reconstruction according to the present invention, relate to the filtered back projection of weighting.Algorithm for reconstructing based on filtered back projection provides the advantage of relatively short running time and relative little computing cost.In another embodiment of the present invention, reconstruction is the reconstruction of the iteration of being undertaken by statistics weighting.The algorithm for reconstructing of iteration provides high-resolution (particularly in edge) and not easily goes out the advantage of artifact.
Although in detail by the detailed diagram of preferred embodiment with describe the present invention, the present invention does not limit by disclosed example, and technical staff can derive other change thus, and does not depart from protection scope of the present invention.
Claims (14)
1. an x-ray unit, can along the longitudinal axis (5) with the projection of the X-ray of the check object of feed speed movement for record, and comprise the record cell that can rotate around the described longitudinal axis (5), wherein, described record cell comprises:
-X-ray emitter (8), for the X-ray of emitting x-ray form, and X-ray detector (9), for detecting described X-ray,
First gap aperture (15) of-stationary positioned, its width having along the longitudinal axis (5) is first opening of D_1, designed to be used the X-ray beam that the level being formed in the longitudinal axis (5) has width D Z_1,
-the second gap aperture (16), its width having along the longitudinal axis (5) is second opening of D_2, designed to be used the X-ray beam that the level being formed in the longitudinal axis (5) has width D Z_2,
Wherein, DZ_2≤DZ_1,
Wherein, can according to described feed speed along the mobile described second gap aperture (16) of the described longitudinal axis (5), make the X-ray beam that is shaped by gap aperture (15,16) only examination object to the contributive region of the radioscopic image of reconstruction tomography.
2. according to x-ray unit according to claim 1, wherein, described check object moves with the first feed speed in helicon mode during prescan, and move with the second feed speed in rear scan period, and wherein, described second gap aperture (16) can move respectively as making X-ray beam can move along the longitudinal axis (5) with the speed identical with described check object during rear scanning with prescan.
3. according to the x-ray unit described in claim 1 or 2, also comprise reconstruction unit (4), it designed to be used the radioscopic image carrying out reconstruction tomography based on the X-ray projection by described x-ray unit record, wherein, described reconstruction is comprised and being weighted according to the intensity of the X-ray be shaped by described gap aperture (15,16).
4. according to x-ray unit according to claim 3, wherein, carry out described weighting binary system.
5. according to x-ray unit according to claim 3, wherein, carry out described weighting pro rata with the intensity of the X-ray be shaped by described gap aperture (15,16).
6. according to the x-ray unit according to any one of claim 3 to 5, wherein, described reconstruction is the filtered back projection of weighting.
7. according to the x-ray unit according to any one of claim 3 to 5, wherein, described reconstruction is the reconstruction of the iteration of being undertaken by statistics weighting.
8. in helicon mode by can rotate around the longitudinal axis (5) recording unit records X-ray projection a method, wherein, described record cell comprises:
-X-ray emitter (8), for the X-ray of emitting x-ray form, and X-ray detector (9), for detecting described X-ray,
First gap aperture (15) of-stationary positioned, its width having along the longitudinal axis (5) is first opening of D_1, designed to be used the X-ray beam that the level being formed in the longitudinal axis (5) has width D Z_1,
-the second gap aperture (16), its width having along the longitudinal axis (5) is second opening of D_2, designed to be used the X-ray beam that the level being formed in the longitudinal axis (5) has width D Z_2,
Wherein, DZ_2≤DZ_1,
Wherein, move check object along the longitudinal axis (5) with feed speed,
Wherein, according to described feed speed along the mobile described second gap aperture (16) of the described longitudinal axis (5), make the X-ray that is shaped by gap aperture (15,16) only examination object to the contributive region of the radioscopic image of reconstruction tomography.
9. in accordance with the method for claim 8, wherein, described check object moves with the first feed speed during prescan, and move with the second feed speed in rear scan period, and wherein, respectively described second gap aperture (16) is moved as making X-ray beam always mobile along the longitudinal axis (5) with the speed identical with described check object during rear scanning with prescan.
10. one kind is carried out the method for the radioscopic image of reconstruction tomography based on the X-ray projection according to the method record described in claim 8 or 9, wherein, described reconstruction is comprised and being weighted according to the intensity of the X-ray be shaped by described gap aperture (15,16).
11. in accordance with the method for claim 10, wherein, carries out described weighting binary system.
12. in accordance with the method for claim 10, wherein, carries out described weighting pro rata with the intensity of the X-ray be shaped by described gap aperture (15,16).
13. according to the method according to any one of claim 10 to 12, and wherein, described reconstruction is the filtered back projection of weighting.
14. according to the method according to any one of claim 10 to 12, and wherein, described reconstruction is the reconstruction of the iteration of being undertaken by statistics weighting.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102013215042.3 | 2013-07-31 | ||
| DE102013215042.3A DE102013215042B4 (en) | 2013-07-31 | 2013-07-31 | X-ray unit with slit diaphragms |
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| Publication Number | Publication Date |
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| CN104337540A true CN104337540A (en) | 2015-02-11 |
| CN104337540B CN104337540B (en) | 2017-07-28 |
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| CN201410371675.7A Active CN104337540B (en) | 2013-07-31 | 2014-07-31 | X-ray unit with gap aperture |
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| Country | Link |
|---|---|
| CN (1) | CN104337540B (en) |
| BR (1) | BR102014018632A2 (en) |
| DE (1) | DE102013215042B4 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112075947A (en) * | 2020-08-24 | 2020-12-15 | 南昌大学第一附属医院 | Real-time X-ray medical image acquisition device and acquisition method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| DE102016221205B4 (en) * | 2016-10-27 | 2018-07-26 | Siemens Healthcare Gmbh | Method for generating X-ray images and X-ray system |
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| CN85106837A (en) * | 1985-09-10 | 1987-03-11 | 老代尔夫特光学工业有限公司 | Slit X-ray photographic equipment |
| CN1685447A (en) * | 2002-09-26 | 2005-10-19 | 西门子公司 | Overlay device and computer tomography device comprising an emitter side overlay device |
| CN1851832A (en) * | 2005-04-22 | 2006-10-25 | 西门子公司 | Diaphragm device for sweeping x-ray apparatus of object and method thereof |
| US20100091937A1 (en) * | 2008-09-30 | 2010-04-15 | Rainer Raupach | X-ray beam modifying diaphragm and diaphragm device |
-
2013
- 2013-07-31 DE DE102013215042.3A patent/DE102013215042B4/en active Active
-
2014
- 2014-07-29 BR BR102014018632A patent/BR102014018632A2/en not_active IP Right Cessation
- 2014-07-31 CN CN201410371675.7A patent/CN104337540B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85106837A (en) * | 1985-09-10 | 1987-03-11 | 老代尔夫特光学工业有限公司 | Slit X-ray photographic equipment |
| CN1685447A (en) * | 2002-09-26 | 2005-10-19 | 西门子公司 | Overlay device and computer tomography device comprising an emitter side overlay device |
| CN1851832A (en) * | 2005-04-22 | 2006-10-25 | 西门子公司 | Diaphragm device for sweeping x-ray apparatus of object and method thereof |
| US20100091937A1 (en) * | 2008-09-30 | 2010-04-15 | Rainer Raupach | X-ray beam modifying diaphragm and diaphragm device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112075947A (en) * | 2020-08-24 | 2020-12-15 | 南昌大学第一附属医院 | Real-time X-ray medical image acquisition device and acquisition method |
| CN112075947B (en) * | 2020-08-24 | 2023-06-16 | 南昌大学第一附属医院 | Real-time X-ray medical image acquisition device and acquisition method |
Also Published As
| Publication number | Publication date |
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| DE102013215042A1 (en) | 2015-02-05 |
| BR102014018632A2 (en) | 2015-09-29 |
| DE102013215042B4 (en) | 2021-09-16 |
| CN104337540B (en) | 2017-07-28 |
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