CA1135881A - Aperture system for radiation sources situated in parallel planes - Google Patents
Aperture system for radiation sources situated in parallel planesInfo
- Publication number
- CA1135881A CA1135881A CA000338382A CA338382A CA1135881A CA 1135881 A CA1135881 A CA 1135881A CA 000338382 A CA000338382 A CA 000338382A CA 338382 A CA338382 A CA 338382A CA 1135881 A CA1135881 A CA 1135881A
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- aperture
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- aperture plates
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- 230000005855 radiation Effects 0.000 title claims abstract description 82
- 238000006073 displacement reaction Methods 0.000 claims abstract description 18
- 238000009826 distribution Methods 0.000 claims abstract description 10
- 230000005540 biological transmission Effects 0.000 claims 1
- 230000036962 time dependent Effects 0.000 abstract 1
- 238000003745 diagnosis Methods 0.000 description 1
- 229920000136 polysorbate Polymers 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
- A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
- A61B6/025—Tomosynthesis
-
- 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
- A61B6/08—Auxiliary means for directing the radiation beam to a particular spot, e.g. using light beams
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
- G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
- G21K1/02—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators
- G21K1/04—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators using variable diaphragms, shutters, choppers
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Medical Informatics (AREA)
- Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Heart & Thoracic Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- Optics & Photonics (AREA)
- Pathology (AREA)
- Radiology & Medical Imaging (AREA)
- Biomedical Technology (AREA)
- Biophysics (AREA)
- Molecular Biology (AREA)
- Surgery (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Spectroscopy & Molecular Physics (AREA)
- General Engineering & Computer Science (AREA)
- Apparatus For Radiation Diagnosis (AREA)
- Radiation-Therapy Devices (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
Abstract
19.9.1979 PHD 78-148 ABSTRACT:
"Aperture system for radiation sources situated in parallel planes".
Aperture plates comprising fixed apertures are suitable to only a limited degree for multiple radiation sources. In order to enable stopping of the radiation beams of a multiple radiation source to the size of an object zone to be examined, use is made of aperture systems com-prising aperture plates which are displaceable parallel to each other. The aperture plates comprise passages whose dis-tribution corresponds to the distribution of the radiation souces. By lateral parallel displacement of the aperture plates, the passages are shifted with respect to each other, so that the passage can be adjusted.Continuously,adjustable apertures can thus be realized. When the radiation sources are situated in different mutually parallel planes, a group of aperture plates must be associated with each plane for continuous stopping of the radiation beams by means of the aperture plates. The dimensions of the passages of the aper-ture plates are then each time dependent of the position of the aperture plates in the beam path of the multiple radia-tion source.
"Aperture system for radiation sources situated in parallel planes".
Aperture plates comprising fixed apertures are suitable to only a limited degree for multiple radiation sources. In order to enable stopping of the radiation beams of a multiple radiation source to the size of an object zone to be examined, use is made of aperture systems com-prising aperture plates which are displaceable parallel to each other. The aperture plates comprise passages whose dis-tribution corresponds to the distribution of the radiation souces. By lateral parallel displacement of the aperture plates, the passages are shifted with respect to each other, so that the passage can be adjusted.Continuously,adjustable apertures can thus be realized. When the radiation sources are situated in different mutually parallel planes, a group of aperture plates must be associated with each plane for continuous stopping of the radiation beams by means of the aperture plates. The dimensions of the passages of the aper-ture plates are then each time dependent of the position of the aperture plates in the beam path of the multiple radia-tion source.
Description
, 19.9.1979 1 PHD 78-148 "Aperture system for radiation sources situated in para:Llel planes".
.
The invention relates to an aperture system for a plurality of radiation sources which are situated in at least one plane, the radiation beams thereof covering at least approximately the same object zone of an object, 5 said laterally displaceable aperture system comprising different successive apertures for each of -the radiation sources in order to stop the corresponding radiation beams, a distribution of the apertures corresponding to a distri-bution of the radiation sources situated in the plane in lO order to achieve optimum image -transmission.
The aper-ture system comprises a flat plate which is situated between the radiation sources and the object.
The plate comprises several groups of fixed apertures, the radiation beams each time passing through a group arriving - 15 from different radiation sources and covering at least approximately the same zone of an object. The size of the apertures within a group is then determined 'by the distance between the corresponding radiation sources and the plate.
The radiation beams can be step-wise adapted to 20 object zones of different dimensions by selection of dif-ferent groups of aper-tures by corresponding lateral dis-placement of the plate. However, because the number of groups of apertures on the plate is limited, the radiation beams can be adapted only to a limited number of different 25 object zones.
Therefore, an aperture sy~s-tem comprising fixed apertures, for example, can be used to only a limited extent for medical X-ray diagnosis, because the dimensi,ons of the object zones vary substantial~y. In addition, in order to 30 reduce the radiation load for the object and also the scattered t~adiation, the individual radiation beams must -- be stopped to such an extent tha-t, whenever possible, they only irradiate th~ object ~one to be examined.
19.9.1979 2 PHD 78-1LI8 The invention has for its object to provide an aperture system whereby radiation beams from various radia-tion sources which are situated in at least one plane can be continuously stopped in a simple manner.
This object in accordance wlth the invention is achieved in that the aperture system consists of a group of at least two aperture plates which are situated parallel to a source plane, each of said plates being provided with passages in order to form apertures and being arranged to be laterally displaceable with respect to each other.
When the radiation sources are situa-ted in only one plane ~radiation source plane), the aperture system may consist of, for example, a group of two aperture plates which are arranged to be mutually displaceable, parallel to 15 the radiation source plane.
~ ue to the use of the mutually parallel displace-able aperture plates it is achieved that the size of the apertures can be continuously adjusted, so that the radia-tion beams from the radiation sources can be fully adapted 20 to the dimensions of the object zone to be examined. To this end, the aperture plates comprise so-termed passages whose distribution on the aperture plates corresponds to the distribution of the radiation sources situated in the plane. Therefore, parallel displacement of the aperture 25 plates causes displacement of the passages with respect to each other, so that they are each time partly covered by the other aperture plate. ~s a result, apertures remain.
The aperture plates may be arranged one directly on the other or parallel to and at a distance from each 30 other, displacement o~ the aperture plates being possible consecutively or simultaneously. Mechanical or electro-mechanical devices can be used for realizing the displace-ment~
A group of aperture plates may also comprise more 35 than two aperture plates. The arrangement and displacement of the apert;ure plates can then also be realized in the ~- described manner.
As a result of the stopping o~ the radiation beams 3~8~
19.9.1979 3 PHD 78-148 to the object zone, irradiation of zones which are not to be examined is avoided. The radiation load for the object is thus reduced. Furthermore, scat-tered radiation produced during irradiation of the object is reduced, so that the 5 resolution and the contrast of the images of the object ~one are increased.
In a preferred embodiment in accordance with the invention, additional groups of aperture plates are pro-vided for stopping the radiation beams of radiation sources lO situated in mutually parallel planes, a group of aperture plates being each time assigned to a plane, the aperture plates of a group each time comprising further apertures for the radiation beams which are not assigned to this group. As a result, such radiation beams can pass through 5 the aperture system in an unobstructed manner in each posi-tion of the corresponding aperture plates.
When the radiation sources are situated in several parallel planes, a group of aperture plates should be assigned to each plane in order to achieve continuous stop-20 ping of the radiation beams by means of aperture plates.The separate groups of aperture plates, which may be situated at a different distance from each other and from the plates each time associated therewith, each time comprise equally large apertures, the size of which, however, may differ for 25 different groups of aperture plates. The aperture plates are positioned in the beam path so that the passing radia-tion beams fully cover the same zone of an object to be examined. The aperture plates comprise additional passages for the radiation beams originating from the planes not 30 associated therewith. However, these radiation beams com-pletely pass through the passages in any position of the aperture plates resulting from parallel displacement, so that they are not additionally stopped.
When the objec-t zone to be examined is increased 35 or decreasecl, the apertures are opened or closed in accor-dance with the distance be-tween the groups and the associa-- ted plates, thus each time necessitating a corresponding parallel displacement of the aperture plates~ The parallel ~9.9.1979 4 PHD 78~ 8 displacement can be realized for all aperture plate~s simul-taneously either by hand or by means o~ mechanical or electromechanical devices~
The invention shows embodiments in accordance 5 with the invention.
Fig. 1 shows an aperture sys-tem consisting of a pair of aperture plates, Fig. 2 is a plan view of the aperture system shown in Fig. 1, and Fig. 3 shows an aperture system consisting of two pairs of aperture plates.
Fig. 1 diagramma-tically shows three X-ray sources 1, 2 and 3 which are situated in a plane E ancl which are arranged together as a multiple radiation source in a common 15 tank (not shown). Each of the three X-ray sources 1, 2 and 3 emits a primary radiation beam L~, 5 and 6, respectively, which reaches an aperture system B which consists o~ two aperture plates Bl and B2 which are arranged one on the other. The aperture system B comprises apertures 7, 8 and 20 9 for stopping the primary radiation beams 4, 5 and 6 to form the radiation beams 10, 11 ancl 12 which fully coincide in a sup~rposition plane 13 which extends parallel to the plane E and which irradia-te subs-tantially the same object zone 1~ situated inside an object 1L~. The object 14 may 25 be, for example, a human body. Because the radiation beams 1~, 11 and 12 fully cover only the object zone 15 to be examined, the smallest volume 16 (denoted by broken lines) causing scattered radiation i5 formed inside the object 14.
The radiation beams 10, 11 and 12 may be incident, for 30 example, on a radiation~sensitive layer, for example, a film 17 or on the entrance screen of an ~-ray image inten-sifier for generating superposition images.
The two aperture plates B1 and B2, ~or example, being situatecl one on the other or in parallel at a small 35 distance from each other, comprise passages 7a, 8a and 9a and 7b, 8b and 9b, respectively, in order to ~orm aper-tures -- 7, 8 and 9, the distribution o~ said passages on the aper-ture plates B1, B2 corresponcling to the distribution o-~ the 1 3~
.
19.9.1979 5 PHD 78-148 X-ray source 1, 2 and 3 in the plane E. By parallel displa-cement of the aperture plates B1, B2 which are made, for : . example, of lead, the passages 7a, b to 9a, b are dis-placed with respect to each oth~r, so that they are partly 5 covered each time by th~ other plate. Thus, openings remain which stop the radiation beams 10, 11 and 12 as apertures 7, 8 and 9.
The aperture plates B1 and B2 can be simultaneous-,either ly moved with respect to each other/by hand or by means o~
1~ an electromechanical device V. Preferably, the aperture system B is mo~nted togehter with the displacement device V on the tank of the multiple radiation source 9 50 that it can be moved together with the multiple radiation source during irradiation of the object zone 15 from different l5 directions.
Figure 2 is a plan view of the aperture system B
of Figure 1 which consists of -~wo aperture plates B1 and B2. Both aperture plates B1 and B2 which are, for example, square and equally large, comprise three passages 7a, 8a, 20 ~a and 7b, 8b, 9b, respec-ti~ely, which have, for exa~lple, a rectangular shape and the same dimensions, their long s~des all extending parallel to each other. They are situa-ted on the two aperture plates B1 and B2 so that they exactly coincide in the non-shifted posit.ion of the aperture 25 plates B1 and B2. In this condition, the radiation beams 1~, 11 and 12 passing through the aperture sys-tem B irra- --diate the largest object zone 15. By parallel displacement of the aperture plates B1 and B2 in one of the directions denoted by the arrows a, b, c or in intermediate directions, 30 the passages of an aperture plate are co~ered each time by the other aperture plateO Thus, the apertures 7, 8 and 9 are formed which are bounded each time by the edges of each time two passages 7a and b, etc. The apertures 7, 8 and 9 .. are then always situated in the centre of the primary radia--35 tion beam.s Ll, 5 and 6. Thus, object zones 15 of dlfferent siæe anci sllape can be irradiated by displacemcllt of the aper-ture plates B1 and B2. Ob~iously, the aperture plates ~1 and B2 can also be rotated with respect to each other around an ., . . . :, ::
- ~ ~3 .;
19.9.1979 6 PHD 78-148 axis which extends perpendicularly to the plane of the plates, ~or example, in order to form ~urther apertures.
Figure 3 shows an aperture system Bl for radiation sources which are arranged in two para:Llel planes. The X-ray 5 sources 19 and 20 are situated in a first plane E1 and are ` associated with a multiple radiation source 18, whilst in - a second plane E2 which is situated underneath and parallel to the first plane E1 a further X-ray source 21 and a radia-tion source 41 which emits visible light are arranged.
The aperture system B' consists of a first pair or aper-ture plates B3 and B4 which are situated one on the other and which are associated with the radia-tion sources 19 and 20 situated in the plane E1, and a second pair of aperture plates B5 and B6 which are also situated one on 15 the other and which are associated with the radiation sources 21 and l~1 situated in-the plane E2. Both pairs of aperture plates are arranged underneath -the radiation sour-ces 19, 20 and 21, 41, the pairs being arranged parallel to each other and parallel to the planes E1 and E2, the second 20pair being situated underneath the first pair. Obviously~
the pairs and the planes may also be arranged in a dlfferent suitable sequence.
The primary radiation beams 19a and 20a emitted by the X-r~y sources 19 and 20 reach the associated aper-25 tures 36 and 37 which are situated in the first pair ofaperture plates B3 and B4 and which are formed by passages which have been displaced with respect to each other (see Figure 2). The apertures 36 and 37 have -the same shape and the same dimensions and are situated in the apertur0 plates 30 B3 and B4 so that the radiation beams 33 and 34 passing therethrough and stopped thereby irradiate the same object zone 27 of an object 28 to be examined and fully coincide in a superposition plane 23 inside the object zone 270 The radiation beams 33 and 3l~ are subsequently incident on a 35 radiation-sensitive layer 30, for example, a X~ray film in order to form superposition images.
In order to prevent interruption of the radiation beams 33 and 3ll by the second pa:ir of` aperture plat0s B5 ~ .
.:
3~8~
.
19.9.1979 7 PHD 78~
and B6, there are provided therein further passages S2 wherethrough the radiation beams 33 and 34 pass completely in an~ position of the parallel displaceable aperture plates B5 and B6. Corresponding passages Sl are provided in the 5 first pair of aperture plates B3 and B4 for the primary radiation beams 21a and 41a of the radiation sources 21 and l~1 situated in the plane E2. A~ter passage through the passages Sl, the primary radiation beams 21a and l~1a reach the associated apertures 35 and 42 which also have the same 10 shape and the same dimensions and which are again formed by corresponding, parallel displaceable passages (see Fi~ure
.
The invention relates to an aperture system for a plurality of radiation sources which are situated in at least one plane, the radiation beams thereof covering at least approximately the same object zone of an object, 5 said laterally displaceable aperture system comprising different successive apertures for each of -the radiation sources in order to stop the corresponding radiation beams, a distribution of the apertures corresponding to a distri-bution of the radiation sources situated in the plane in lO order to achieve optimum image -transmission.
The aper-ture system comprises a flat plate which is situated between the radiation sources and the object.
The plate comprises several groups of fixed apertures, the radiation beams each time passing through a group arriving - 15 from different radiation sources and covering at least approximately the same zone of an object. The size of the apertures within a group is then determined 'by the distance between the corresponding radiation sources and the plate.
The radiation beams can be step-wise adapted to 20 object zones of different dimensions by selection of dif-ferent groups of aper-tures by corresponding lateral dis-placement of the plate. However, because the number of groups of apertures on the plate is limited, the radiation beams can be adapted only to a limited number of different 25 object zones.
Therefore, an aperture sy~s-tem comprising fixed apertures, for example, can be used to only a limited extent for medical X-ray diagnosis, because the dimensi,ons of the object zones vary substantial~y. In addition, in order to 30 reduce the radiation load for the object and also the scattered t~adiation, the individual radiation beams must -- be stopped to such an extent tha-t, whenever possible, they only irradiate th~ object ~one to be examined.
19.9.1979 2 PHD 78-1LI8 The invention has for its object to provide an aperture system whereby radiation beams from various radia-tion sources which are situated in at least one plane can be continuously stopped in a simple manner.
This object in accordance wlth the invention is achieved in that the aperture system consists of a group of at least two aperture plates which are situated parallel to a source plane, each of said plates being provided with passages in order to form apertures and being arranged to be laterally displaceable with respect to each other.
When the radiation sources are situa-ted in only one plane ~radiation source plane), the aperture system may consist of, for example, a group of two aperture plates which are arranged to be mutually displaceable, parallel to 15 the radiation source plane.
~ ue to the use of the mutually parallel displace-able aperture plates it is achieved that the size of the apertures can be continuously adjusted, so that the radia-tion beams from the radiation sources can be fully adapted 20 to the dimensions of the object zone to be examined. To this end, the aperture plates comprise so-termed passages whose distribution on the aperture plates corresponds to the distribution of the radiation sources situated in the plane. Therefore, parallel displacement of the aperture 25 plates causes displacement of the passages with respect to each other, so that they are each time partly covered by the other aperture plate. ~s a result, apertures remain.
The aperture plates may be arranged one directly on the other or parallel to and at a distance from each 30 other, displacement o~ the aperture plates being possible consecutively or simultaneously. Mechanical or electro-mechanical devices can be used for realizing the displace-ment~
A group of aperture plates may also comprise more 35 than two aperture plates. The arrangement and displacement of the apert;ure plates can then also be realized in the ~- described manner.
As a result of the stopping o~ the radiation beams 3~8~
19.9.1979 3 PHD 78-148 to the object zone, irradiation of zones which are not to be examined is avoided. The radiation load for the object is thus reduced. Furthermore, scat-tered radiation produced during irradiation of the object is reduced, so that the 5 resolution and the contrast of the images of the object ~one are increased.
In a preferred embodiment in accordance with the invention, additional groups of aperture plates are pro-vided for stopping the radiation beams of radiation sources lO situated in mutually parallel planes, a group of aperture plates being each time assigned to a plane, the aperture plates of a group each time comprising further apertures for the radiation beams which are not assigned to this group. As a result, such radiation beams can pass through 5 the aperture system in an unobstructed manner in each posi-tion of the corresponding aperture plates.
When the radiation sources are situated in several parallel planes, a group of aperture plates should be assigned to each plane in order to achieve continuous stop-20 ping of the radiation beams by means of aperture plates.The separate groups of aperture plates, which may be situated at a different distance from each other and from the plates each time associated therewith, each time comprise equally large apertures, the size of which, however, may differ for 25 different groups of aperture plates. The aperture plates are positioned in the beam path so that the passing radia-tion beams fully cover the same zone of an object to be examined. The aperture plates comprise additional passages for the radiation beams originating from the planes not 30 associated therewith. However, these radiation beams com-pletely pass through the passages in any position of the aperture plates resulting from parallel displacement, so that they are not additionally stopped.
When the objec-t zone to be examined is increased 35 or decreasecl, the apertures are opened or closed in accor-dance with the distance be-tween the groups and the associa-- ted plates, thus each time necessitating a corresponding parallel displacement of the aperture plates~ The parallel ~9.9.1979 4 PHD 78~ 8 displacement can be realized for all aperture plate~s simul-taneously either by hand or by means o~ mechanical or electromechanical devices~
The invention shows embodiments in accordance 5 with the invention.
Fig. 1 shows an aperture sys-tem consisting of a pair of aperture plates, Fig. 2 is a plan view of the aperture system shown in Fig. 1, and Fig. 3 shows an aperture system consisting of two pairs of aperture plates.
Fig. 1 diagramma-tically shows three X-ray sources 1, 2 and 3 which are situated in a plane E ancl which are arranged together as a multiple radiation source in a common 15 tank (not shown). Each of the three X-ray sources 1, 2 and 3 emits a primary radiation beam L~, 5 and 6, respectively, which reaches an aperture system B which consists o~ two aperture plates Bl and B2 which are arranged one on the other. The aperture system B comprises apertures 7, 8 and 20 9 for stopping the primary radiation beams 4, 5 and 6 to form the radiation beams 10, 11 ancl 12 which fully coincide in a sup~rposition plane 13 which extends parallel to the plane E and which irradia-te subs-tantially the same object zone 1~ situated inside an object 1L~. The object 14 may 25 be, for example, a human body. Because the radiation beams 1~, 11 and 12 fully cover only the object zone 15 to be examined, the smallest volume 16 (denoted by broken lines) causing scattered radiation i5 formed inside the object 14.
The radiation beams 10, 11 and 12 may be incident, for 30 example, on a radiation~sensitive layer, for example, a film 17 or on the entrance screen of an ~-ray image inten-sifier for generating superposition images.
The two aperture plates B1 and B2, ~or example, being situatecl one on the other or in parallel at a small 35 distance from each other, comprise passages 7a, 8a and 9a and 7b, 8b and 9b, respectively, in order to ~orm aper-tures -- 7, 8 and 9, the distribution o~ said passages on the aper-ture plates B1, B2 corresponcling to the distribution o-~ the 1 3~
.
19.9.1979 5 PHD 78-148 X-ray source 1, 2 and 3 in the plane E. By parallel displa-cement of the aperture plates B1, B2 which are made, for : . example, of lead, the passages 7a, b to 9a, b are dis-placed with respect to each oth~r, so that they are partly 5 covered each time by th~ other plate. Thus, openings remain which stop the radiation beams 10, 11 and 12 as apertures 7, 8 and 9.
The aperture plates B1 and B2 can be simultaneous-,either ly moved with respect to each other/by hand or by means o~
1~ an electromechanical device V. Preferably, the aperture system B is mo~nted togehter with the displacement device V on the tank of the multiple radiation source 9 50 that it can be moved together with the multiple radiation source during irradiation of the object zone 15 from different l5 directions.
Figure 2 is a plan view of the aperture system B
of Figure 1 which consists of -~wo aperture plates B1 and B2. Both aperture plates B1 and B2 which are, for example, square and equally large, comprise three passages 7a, 8a, 20 ~a and 7b, 8b, 9b, respec-ti~ely, which have, for exa~lple, a rectangular shape and the same dimensions, their long s~des all extending parallel to each other. They are situa-ted on the two aperture plates B1 and B2 so that they exactly coincide in the non-shifted posit.ion of the aperture 25 plates B1 and B2. In this condition, the radiation beams 1~, 11 and 12 passing through the aperture sys-tem B irra- --diate the largest object zone 15. By parallel displacement of the aperture plates B1 and B2 in one of the directions denoted by the arrows a, b, c or in intermediate directions, 30 the passages of an aperture plate are co~ered each time by the other aperture plateO Thus, the apertures 7, 8 and 9 are formed which are bounded each time by the edges of each time two passages 7a and b, etc. The apertures 7, 8 and 9 .. are then always situated in the centre of the primary radia--35 tion beam.s Ll, 5 and 6. Thus, object zones 15 of dlfferent siæe anci sllape can be irradiated by displacemcllt of the aper-ture plates B1 and B2. Ob~iously, the aperture plates ~1 and B2 can also be rotated with respect to each other around an ., . . . :, ::
- ~ ~3 .;
19.9.1979 6 PHD 78-148 axis which extends perpendicularly to the plane of the plates, ~or example, in order to form ~urther apertures.
Figure 3 shows an aperture system Bl for radiation sources which are arranged in two para:Llel planes. The X-ray 5 sources 19 and 20 are situated in a first plane E1 and are ` associated with a multiple radiation source 18, whilst in - a second plane E2 which is situated underneath and parallel to the first plane E1 a further X-ray source 21 and a radia-tion source 41 which emits visible light are arranged.
The aperture system B' consists of a first pair or aper-ture plates B3 and B4 which are situated one on the other and which are associated with the radia-tion sources 19 and 20 situated in the plane E1, and a second pair of aperture plates B5 and B6 which are also situated one on 15 the other and which are associated with the radiation sources 21 and l~1 situated in-the plane E2. Both pairs of aperture plates are arranged underneath -the radiation sour-ces 19, 20 and 21, 41, the pairs being arranged parallel to each other and parallel to the planes E1 and E2, the second 20pair being situated underneath the first pair. Obviously~
the pairs and the planes may also be arranged in a dlfferent suitable sequence.
The primary radiation beams 19a and 20a emitted by the X-r~y sources 19 and 20 reach the associated aper-25 tures 36 and 37 which are situated in the first pair ofaperture plates B3 and B4 and which are formed by passages which have been displaced with respect to each other (see Figure 2). The apertures 36 and 37 have -the same shape and the same dimensions and are situated in the apertur0 plates 30 B3 and B4 so that the radiation beams 33 and 34 passing therethrough and stopped thereby irradiate the same object zone 27 of an object 28 to be examined and fully coincide in a superposition plane 23 inside the object zone 270 The radiation beams 33 and 3l~ are subsequently incident on a 35 radiation-sensitive layer 30, for example, a X~ray film in order to form superposition images.
In order to prevent interruption of the radiation beams 33 and 3ll by the second pa:ir of` aperture plat0s B5 ~ .
.:
3~8~
.
19.9.1979 7 PHD 78~
and B6, there are provided therein further passages S2 wherethrough the radiation beams 33 and 34 pass completely in an~ position of the parallel displaceable aperture plates B5 and B6. Corresponding passages Sl are provided in the 5 first pair of aperture plates B3 and B4 for the primary radiation beams 21a and 41a of the radiation sources 21 and l~1 situated in the plane E2. A~ter passage through the passages Sl, the primary radiation beams 21a and l~1a reach the associated apertures 35 and 42 which also have the same 10 shape and the same dimensions and which are again formed by corresponding, parallel displaceable passages (see Fi~ure
2)~ The aperture 35 is situated in -the aperture plates B5, B6 so that the beam 22 stopped thereby fully irradiates the sa~le object ~one 27 as the radiation beams 33, 34 or the 15 same superposition plane 23. The radia-tion beam 22 or the radiation source 21 then serves ~or finding and adjusting ; the desired object zone 27.
The light beam ~ stopped by the aperture 42 forms a light spot 45 on the object 28, said spot corresponding 20to the dimensions of the object zone 27; by means of this spot, the object 28 which is situated on a table 29 can also be positioned in the case of displacement in different dire~
tions XYZ relatively with respect to the radiation beams 22, 33, 34.
In accordance wi-th the distance between the indi vidual aperture plate pairs and the planes E1 and E2 with which they are associated, apertures 36, 37 and 35, 42 of different size must be adjusted by parallel displacement of aperture plates during the stopping of an object zone 27,-the 30displacement of the pairs of aperture plates also being de-pendent of this distance. When the quotient o~ the distance d1 between -the firs-t pair of plates B3 and B~l and the plane El and the distance d2 between the s~perposition plane 23 and the plane E1 is chosen to be equal to the quotient of 35the distance d3 between the second pair of aperture plates B5 and B6 and the plane E2 and -the distance d~ between the superposition plane 23 and the plane ~2, the following is applicable.
The light beam ~ stopped by the aperture 42 forms a light spot 45 on the object 28, said spot corresponding 20to the dimensions of the object zone 27; by means of this spot, the object 28 which is situated on a table 29 can also be positioned in the case of displacement in different dire~
tions XYZ relatively with respect to the radiation beams 22, 33, 34.
In accordance wi-th the distance between the indi vidual aperture plate pairs and the planes E1 and E2 with which they are associated, apertures 36, 37 and 35, 42 of different size must be adjusted by parallel displacement of aperture plates during the stopping of an object zone 27,-the 30displacement of the pairs of aperture plates also being de-pendent of this distance. When the quotient o~ the distance d1 between -the firs-t pair of plates B3 and B~l and the plane El and the distance d2 between the s~perposition plane 23 and the plane E1 is chosen to be equal to the quotient of 35the distance d3 between the second pair of aperture plates B5 and B6 and the plane E2 and -the distance d~ between the superposition plane 23 and the plane ~2, the following is applicable.
3~
19.9.1979 8 PHD 78-148 d1 d3 d2 d4 Thus, ~or equally large apertures in both aperture plate pairs, the aperture plates B3, B5 and B4, B6, which are 5 each time situated on one side can be mechanically inter connected for uniform displacement.
' . ..
19.9.1979 8 PHD 78-148 d1 d3 d2 d4 Thus, ~or equally large apertures in both aperture plate pairs, the aperture plates B3, B5 and B4, B6, which are 5 each time situated on one side can be mechanically inter connected for uniform displacement.
' . ..
Claims (7)
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PRO-PERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An aperture system for a plurality of radiation sources which are situated in at least one plane, the radia-tion beams thereof covering at least approximately the same object zone of an object, said aperture system comprising different successive apertures for each of the radiation sources in order to stop the corresponding radiation beams, a distribution of the apertures corresponding to a distribu-tion of the radiation sources situated in the plane in order to obtain optimum image transmission, characterized in that the aperture system (B) consists of a group of at least two aperture plates (B1 and B2) which are situated parallel to the plane (E) and which are provided each time with passages (7a, b - 9a, b) in order to form the apertures (7, 8, 9), said plates being arranged to be laterally displaceable with respect to each other.
2. An aperture system as claimed in Claim 1, char-acterized in that for the stopping of the radiation beams of radiation sources situated in mutually parallel planes (E1 and E2) there are provided additional groups of aperture plates, a group of aperture plates being each time associated with a plane, the aperture plates comprising each time a group of further passages (S1, S2) for the radiation beams originating from the planes not associated with this group, the latter beams passing completely through the passages in any position of the relevant aperture plates.
3. An aperture system as claimed in Claim 1, characterized in that the groups consist of pairs of aper-ture plates.
4. An aperture system as claimed in Claim 1, 2 or 3, characterized in that the aperture plates (B1 and B2) of each time a pair are mechanically linked, via a displace-ment device (V), in order to perform a linked movement.
5. An aperture system as claimed in Claim 2 or 3, characterized in that the aperture plates of the pairs which are situated on the same side are each time mechanically linked for simultaneous displacement.
PHD. 78-148.
PHD. 78-148.
6. An aperture system as claimed in Claim 2, char-acterized in that the aperture plates are pairwise-arranged in direct contact with each other.
7. An aperture system as claimed in Claim 1, char-acterized in that the passage have a rectangular shape.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2847011A DE2847011C2 (en) | 1978-10-28 | 1978-10-28 | Device for generating layer images of a three-dimensional body |
| DE2847011.3 | 1978-10-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1135881A true CA1135881A (en) | 1982-11-16 |
Family
ID=6053377
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000338382A Expired CA1135881A (en) | 1978-10-28 | 1979-10-25 | Aperture system for radiation sources situated in parallel planes |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5560900A (en) |
| CA (1) | CA1135881A (en) |
| DE (1) | DE2847011C2 (en) |
| ES (1) | ES485429A1 (en) |
| FR (1) | FR2440014A1 (en) |
| GB (1) | GB2035769B (en) |
| IT (1) | IT1125599B (en) |
| NL (1) | NL7907806A (en) |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3121324A1 (en) * | 1981-05-29 | 1982-12-16 | Philips Patentverwaltung Gmbh, 2000 Hamburg | TOMOSYNTHESIS DEVICE |
| DE3136806A1 (en) * | 1981-09-16 | 1983-03-31 | Siemens AG, 1000 Berlin und 8000 München | X-RAY EXAMINATION DEVICE |
| EP0142841A3 (en) * | 1983-11-18 | 1987-04-29 | Kabushiki Kaisha Toshiba | Aperture device of radiation diagnostic apparatus |
| DE3420760A1 (en) * | 1984-06-04 | 1985-12-05 | Bayer Ag, 5090 Leverkusen | LIGHTING DEVICE FOR THE OPTICAL, IN PARTICULAR IMAGE ANALYTICAL EVALUATION OF MICROBIOLOGICAL OBJECTS |
| DE3434634A1 (en) * | 1984-09-21 | 1986-04-03 | Eichner, Wolf D., Dr.jur., 8630 Coburg | RECORDING CAMERA FOR PRODUCING A PICTURE |
| FR2597054B1 (en) * | 1986-04-15 | 1993-11-26 | Pomagalski Sa | TELESCOPE WITH AUTOMATIC CONTROL OF SEAT PROTECTION DEVICES |
| DE3852009D1 (en) * | 1987-12-11 | 1994-12-08 | Varian International Ag | Therapy simulator. |
| US8681936B2 (en) | 2006-11-10 | 2014-03-25 | Elekta Ab (Publ) | Radiotherapeutic apparatus |
| JP5247363B2 (en) | 2008-11-11 | 2013-07-24 | キヤノン株式会社 | X-ray equipment |
| JP5403605B2 (en) * | 2009-06-29 | 2014-01-29 | 独立行政法人日本原子力研究開発機構 | Radiation irradiation equipment |
| US8406374B2 (en) * | 2010-06-25 | 2013-03-26 | Rigaku Innovative Technologies, Inc. | X-ray optical systems with adjustable convergence and focal spot size |
| RU2589720C2 (en) | 2010-09-06 | 2016-07-10 | Конинклейке Филипс Электроникс Н.В. | X-ray imaging system with detector containing pixels |
| JP5555353B2 (en) * | 2013-04-08 | 2014-07-23 | キヤノン株式会社 | X-ray equipment |
| WO2014180809A1 (en) * | 2013-05-08 | 2014-11-13 | Koninklijke Philips N.V. | Collimation for distanced focal spots |
| DE102016204870B4 (en) * | 2016-03-23 | 2023-11-23 | Siemens Healthcare Gmbh | Aperture device for collimating an X-ray beam from an X-ray device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3840747A (en) * | 1973-04-09 | 1974-10-08 | A Macovski | Gamma ray imaging system |
| US3936639A (en) * | 1974-05-01 | 1976-02-03 | Raytheon Company | Radiographic imaging system for high energy radiation |
| DE2748687C2 (en) * | 1977-10-29 | 1986-08-07 | Philips Patentverwaltung Gmbh, 2000 Hamburg | Device for subdividing radiation from a multiple radiation source penetrating a three-dimensional object into any radiation subgroups |
-
1978
- 1978-10-28 DE DE2847011A patent/DE2847011C2/en not_active Expired
-
1979
- 1979-09-28 FR FR7924163A patent/FR2440014A1/en active Granted
- 1979-10-24 NL NL7907806A patent/NL7907806A/en not_active Application Discontinuation
- 1979-10-25 JP JP13711479A patent/JPS5560900A/en active Granted
- 1979-10-25 IT IT26785/79A patent/IT1125599B/en active
- 1979-10-25 GB GB7937144A patent/GB2035769B/en not_active Expired
- 1979-10-25 CA CA000338382A patent/CA1135881A/en not_active Expired
- 1979-10-26 ES ES485429A patent/ES485429A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| IT1125599B (en) | 1986-05-14 |
| GB2035769A (en) | 1980-06-18 |
| IT7926785A0 (en) | 1979-10-25 |
| ES485429A1 (en) | 1980-05-16 |
| NL7907806A (en) | 1980-05-01 |
| GB2035769B (en) | 1983-07-27 |
| JPS6327677B2 (en) | 1988-06-03 |
| DE2847011C2 (en) | 1983-01-05 |
| DE2847011A1 (en) | 1980-05-08 |
| FR2440014A1 (en) | 1980-05-23 |
| JPS5560900A (en) | 1980-05-08 |
| FR2440014B1 (en) | 1983-11-18 |
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