CN85106558A

CN85106558A - Narrow slit x-ray photographic apparatus

Info

Publication number: CN85106558A
Application number: CN85106558.9A
Authority: CN
Inventors: 西蒙·杜英克; 雨果·夫拉斯布劳姆
Original assignee: Optische Industrie de Oude Delft NV
Current assignee: Optische Industrie de Oude Delft NV
Priority date: 1985-08-31
Filing date: 1985-08-31
Publication date: 1987-03-18
Also published as: CN1003819B

Abstract

The present invention includes through the slit door screen is the X line source that the fan-shaped X line in plane scans to the emitting object body and function substantially, the X wire harness that passes object shines that this device on the X thread detector comprises and a plurality of controlled attenuating elements of diaphragm concerted action, and each element can influence the part of X wire harness under the signal controlling that radiation detecting apparatus produces.Radiation detecting apparatus between emitting object and X thread detector, comprising at least one stretch into all the time in the X wire harness that passes object and with the radiation detector of its scanning motion synchronization action.This detecting device is divided into a plurality of parts with corresponding with the X wire harness each several part of attenuating elements influence, and every part produces the signal of control attenuating elements during work.

Description

Narrow slit X-ray photographic apparatus

The present invention relates to a kind of device that is used for narrow slit X-ray according to elephant, comprising an x-ray source, utilize this x-ray source can with one basically the object of fan-shaped x-ray beam by slit diaphragm butt joint raying on plane scan, the scanning X-ray beam by this object is radiated on the X thread detector simultaneously.

Comprise that to this device with the controlled attenuating elements of slit diaphragm collaborative work is described in No. 8400845, the Netherlands patent applications of unsettled (copending) jointly, this patented claim is quoted as reference at this.The several method that produces the required control signal of attenuating elements has been described in No. 8400845, the Netherlands patent applications.In most cases illustrated in No. 8400845, the Netherlands patent applications, in order to reach this purpose, a series of light detectors that the X line detector that is adopted exports a side that are placed in have been used, each light detector is corresponding with a part of slit diaphragm, and control the concerted action of this part and attenuating elements by control device, or control this part and one group of attenuating elements concerted action.

Yet, when utilizing lighttight X line film cassette, can not use this technology in a simple manner as X-ray detector.

Therefore, an object of the present invention is to design a kind of narrow slit X-ray photographic apparatus, comprising with the controlled attenuating elements of a slit diaphragm collaborative work, its cooperative mode is, even adopted lighttight X-ray film magazine, still available a kind of simple relatively and reliable mode obtains the required control signal of attenuating elements.

In order to reach this effect, according to the present invention, the above-mentioned type device is characterised in that; Comprise and a plurality of controlled attenuating elements of slit diaphragm concerted action that each element is used under the control by the signal that radiation detecting apparatus produced, a part of X-ray scanning bundle is exerted one's influence; This radiation detecting apparatus is placed between the object and X-ray detector of accepting radiation; This radiation detecting apparatus comprises that at least one is all visited at any time and reaches among the scanning X wire harness that penetrates object, and with the radiation detector of the scanning motion synchronization action of this X wire harness.This radiation detecting apparatus be divided into can be by the corresponding part of each sections of the scanning X wire harness of attenuating elements influence, during work, each of radiation detector partly produces a signal that can be used for controlling attenuating elements.

As can be seen, the present invention promptly can be used for using the situation of light tight X-ray film magazine, also can be used for using the occasion of any other type X-ray detector.

Hereinafter with reference to accompanying drawing, for example the several embodiments according to device of the present invention are illustrated, in the accompanying drawings:

Schematically illustrated first embodiment of Fig. 1 according to device of the present invention;

A kind of version of the schematically illustrated Fig. 1 of Fig. 2;

Fig. 3 illustrates the another kind of version of Fig. 2;

Fig. 4 illustrates a kind of modification of Fig. 3; With

Fig. 5 illustrates a kind of modification of Fig. 4.

Schematically illustrated first embodiment of the present invention of Fig. 1 has wherein shown the x-ray source 1 with x-ray focus 2.At work, x-ray source produces X-ray beam B, wherein is essentially the fan-shaped a part of B ' in plane and almost can both passes slit S on the slit diaphragm 3.In addition, accept the object 4 of radiation shown in the figure and place this object X-ray detector 5 afterwards, this detecting device 5 is installed among the unshowned shell.This X-ray detector can be any general type, but is to be made of a lighttight X-ray film magazine in the present embodiment, comprising an XRF screen 6 and the X-ray film 7 that places thereafter.In some X-ray film magazine, second XRF screen has been installed also after the X-ray film.Except this film cassette, the X ray picture image intensifier tube that also can adopt static X ray picture image intensifier tube with big entr screen or employing to have fillet formula input screen.In the later case, the X ray picture image intensifier tube is carried out scanning motion at work.

Shown in situation in, the X-ray beam B ' that passes slit diaphragm only is radiated on the long and narrow part of object 4 imaging on the input screen of X-ray detector of this some.Shown in numeral 10.In order to obtain the more most image of this object, X-ray beam is suitable for carrying out scanning motion in illustrated plane.This can be achieved by diverse ways, for example by making slit diaphragm press the direction motion of arrow 8 indications.These do not constitute some of the present invention.Slit diaphragm and a plurality of controlled attenuating elements 9 concerted actions.A plurality of attenuating elements parallel arranged and can being placed in such a way on the limit promptly, make attenuating elements under the influence of appropriate control signals, can either large or small amplitude differently visit to reach by maybe will be by among the light beam B ' of slit S.Like this, as illustrated in No. 8400845, the Netherlands patent applications.X-ray beam can be instantaneous ground and be attenuated big or lesser extent partly.As can be seen, the slit of slit diaphragm can be in level, vertical or position intermediate, and scanning then can be by vertically, and level or middle direction are carried out.

Should control attenuating elements according to the intensity of the X ray that passes object.For this reason, according to the present invention, used and be arranged on the object 4 of accepting radiation and the radiation detecting apparatus between the X-ray detector, the mounting means of this radiation detecting apparatus can both come out the radiation detection of passing object it at any time, this detection can be respectively at corresponding with attenuating elements 9 or with the corresponding X-ray beam that passes object of one group of this attenuating elements each partly.

According to the present invention, adopted radiation detecting apparatus for this reason, this device is carried out scanning motion between object and X-ray detector, and the scanning motion of being undertaken by X-ray beam B ' in this scanning motion and the course of work is synchronous.

In order to reach this effect, this radiation detecting apparatus has carried out machinery or dynamo-electric coupling with the device that makes X-ray beam carry out scanning motion.Radiation detecting apparatus can be placed in before the X-ray detector 5, and carries out vertical scan motion when work.

In the embodiment depicted in fig. 1, radiation detecting apparatus is fixed on from slit diaphragm on the arm 11 that the X-ray detector direction stretches out.As shown in arrow 12, this arm is suitable for a relative reality or empty turning axle and rotates, and this turning axle stretches along the direction perpendicular to the figure paper plane by x-ray focus 2.This arm all is in outside the scope of the X-ray beam that passes slit diaphragm at any time.Arm 11 can suitably be fixed on the slit diaphragm, and is as shown in fig. 1, synchronous with the action of the action that guarantees arm and the slit diaphragm scanning motion of X-ray beam (thereby also comprise).Yet being fixedly connected of this arm and slit diaphragm is not requisite.Importantly arm will be done with X-ray beam B ' and be synchronized with the movement.

This arm extended beyond the object of accepting radiation, and on the end that extends surpassing object an additional arm 13 is arranged, additional arm 13 has an XRF screen 14 on the end away from arm 11.

XRF screen 14 all extend among the X-ray beam that passes object at any time at least partially and forms radiation detector itself.Additional arm 13 also has the lens 15 of a series of parallel arranged.The number of lens 15 is corresponding with the number of attenuating elements or group number.Lens make these lens all be in outside the X-ray beam that passes object at any time at the mounting means on the additional arm 13.Each lens all is used to be collected in the X that shines on the XRF screen and penetrates under the influence of radiation, the light that produces on the specific portion of XRF screen.

Above-mentioned specific portion also corresponding to X-ray beam B ' each partly, this X-ray beam can be to have passed maybe to pass slit diaphragm, and the influence of can be subjected to declining part element 9 or one group of attenuating elements.

The light that each lens all is used for collecting focuses on same corresponding signal transmission device 16 fixing on the subassembly of

arm

11 and 13, as, the photodetector of the corresponding electric signal of brightness of transmission and light.This electric signal is applied on the control device 18 shown in the figure by line 17.Control device 18 is produced the control signal that is used to control with the relevant corresponding attenuating elements of photodetector by the signal that receives.

In the embodiment illustrated, video screen 14 is mounted to the X-ray scanning bundle and is kept at an angle, and available so relatively thin screen obtains stronger relatively light output.Yet this is not essential.Nature, video screen should be designed to the minimum that decays to the generation of X-ray scanning bundle.

XRF screen 14 can be the screen that launches with respect to the drawing flat transverse.Yet, if each of X-ray beam needs better separation between partly, this screen also can be by some parallel arranged but the screen that separates each other partly form.

Arm

11,13 or similar respective members have wherein been omitted in a distortion of the schematically illustrated radiation detecting apparatus shown in Figure 1 of Fig. 2.X-ray scanning bundle by slit diaphragm is represented with label 20 in Fig. 2.Before inciding X-ray film magazine 7 or other visual X-ray detector, X-ray beam 20 has passed the luminescent crystal element 21 of a series of parallel arranged, such element has been shown among Fig. 2, and these elements can adopt as the iodate germanium crystal, and luminous under the effect of X ray.Each luminescent crystal element can carry out optically-coupled with a photodetector 22, this photodetector is in response to the luminescent crystal element that is associated, produce an electric signal, this electric signal is applied to generate the control signal of control respective attenuation element or corresponding one group of attenuating elements again.

In order to increase effective light output that crystal element takes place, preferably each luminescent crystal element except with the one side of photodetector coupling, on all sides, all scribble reflection horizon to the inside.This layer also can make the luminescent crystal element avoid external action simultaneously, for example influence of wet steam, and it is suitable doing like this, because luminescent crystal all has the characteristic of moisture absorption usually.

Fig. 3 illustrates second kind of distortion according to radiation detecting apparatus of the present invention.The X-ray scanning bundle is still with label 20 expressions.Not a series of luminescent crystal elements as used herein, but the ionization chamber 30 of a series of parallel arranged, ionization chamber shown in the figure.Each ionization chamber comprises two electrodes 31 and 32.Between electrode, exist voltage difference.When ionization chamber is shone by high-octane radioactive ray (for example X ray), will in electrode 31 and circuit that 32 are connected, produce an electric current, same, can therefrom obtain to control the control signal of one or more corresponding attenuating elements.

Certainly, from the direction of scanning beam 20, the antetheca of ionization chamber and rear wall should be made by the material unattenuated or X ray of decaying hardly at least.

Here also can not use the ionization chamber of several separation, and use the ionization chamber of an independent strip, this ionization chamber has a public electrode along the whole length extending of ionization chamber, promptly cross out the figure paper plane, and the electrode of several separation, derive the control signal that is used for the respective attenuation element from this separate mesh electrode.

The ionization chamber of representing this strip among Fig. 4 with label 40.Public electrode is by 41 expressions, and each electrode relative with public electrode be by 42a ... e represents.Public electrode can be regarded as interconnective a plurality of separate mesh electrode.So mutual connection can be arranged in the strip ionization chamber also outside this chamber.

Figure 5 illustrates the vertical view of a mixed form of the embodiment of Fig. 3 and radiation detector shown in Figure 4.Strip ionization chamber 50 comprises some separators of being made by synthetic plastics material 51, as mylar.Space between separator has just formed ionization chamber.Overlook there is shown X-ray scanning bundle 20, arrow 52 is pointed out its direction.Separator preferably points to the x-ray focus direction.

As can be seen, understood after the foregoing, the skilled person in the affiliated field can make various modifications at an easy rate.These modifications are regarded as not exceeding scope of the present invention.

Claims

1, a kind of narrow slit X-ray photographic apparatus, comprise an x-ray source, utilize this x-ray source that a branch of fan-shaped X ray in plane that is essentially by a slit diaphragm is scanned an object of accepting radiation, the scanning X-ray beam that passes this object shines on the X-ray detector, it is characterized in that:

This device comprises a plurality of controlled attenuating elements with the slit diaphragm concerted action, and each element is used to influence a part of scanning X-ray beam under the control of the signal that is produced by a radiation detecting apparatus;

This radiation detecting apparatus is positioned between the object and X-ray detector of accepting radiation;

This radiation detecting apparatus comprises at least one radiation detector, this radiation detector is all visited at any time and is reached among the scanning X-ray beam that passes object and be synchronized with the movement with the scanning motion of X-ray beam, this radiation detecting apparatus is separated into a plurality of parts, so that each part corresponding to the scanning X-ray beam that influenced by attenuating elements, simultaneously, when work, each part of this radiation detecting apparatus all produces a signal that can be used for controlling attenuating elements.

2, according to the device of claim 1, it is characterized in that: this radiation detector comprises an XRF screen, and its radiation detecting apparatus comprises the lens that place a plurality of parallel arranged outside the scanning X-ray beam scope in addition, each lens is used to be collected in the light that produces on the given part of XRF screen under the effect that scans X-ray beam, and guide above-mentioned light into an attached photodetector, light signal is converted to electric signal.

3, according to the device of claim 2, it is characterized in that: the part that its XRF screen is divided into a plurality of parallel arranged and isolates mutually.

4, according to the device of claim 2, it is characterized in that: its XRF screen stretches into the scanning X-ray beam with acute angle.

5, according to the device of claim 1, it is characterized in that: its radiation detector comprises the luminescent crystal element of a plurality of parallel arranged, and the scanning X-ray beam one side in addition that is in of each element is carried out optically-coupled with the photodetector that produces electric signal.

6, according to the device of claim 5, it is characterized in that: each luminescent crystal element except with the part of photodetector coupling whole outside surfaces all scribble to the inside reflection horizon.

7, according to the device of claim 1, it is characterized in that: its radiation detector comprises the ionization chamber of a plurality of parallel arranged, and each ionization chamber has two electrodes respect to one another, and electrode conduction electric current when work is therefrom derived the control signal that is used for attenuating elements.

8, according to the device of claim 7, it is characterized in that: its a plurality of ionization chambers are combined into a strip ionization chamber, and this ionization chamber has first electrode and second shared electrode that a plurality of separation are settled.

9, device according to Claim 8 is characterized in that: each is to having settled a separator between the first adjacent electrode in the ionization chamber of strip.

10, according to the device of claim 9, it is characterized in that: in each separator, each all points to the focus of x-ray source.

11, according to the device of claim 1, it is characterized in that: its radiation detecting apparatus is fixed on the arm, this arm is stretched and surpasses the object of accepting radiation to the X-ray detector direction by slit diaphragm, above-mentioned arm can be respectively rotates in vertical and plane level, these planes correspond respectively to the straight line along level and vertical direction stretching, extension by the x-ray source focus, and above-mentioned arm is equipped with an additional arm that has radiation detector at its end near X-ray detector.