EP0438345A1 - Thin blade collimator - Google Patents

Thin blade collimator Download PDF

Info

Publication number
EP0438345A1
EP0438345A1 EP91400075A EP91400075A EP0438345A1 EP 0438345 A1 EP0438345 A1 EP 0438345A1 EP 91400075 A EP91400075 A EP 91400075A EP 91400075 A EP91400075 A EP 91400075A EP 0438345 A1 EP0438345 A1 EP 0438345A1
Authority
EP
European Patent Office
Prior art keywords
blades
collimator
radiation
grooves
silicon
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP91400075A
Other languages
German (de)
French (fr)
Inventor
Edouard Roudaut
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Publication of EP0438345A1 publication Critical patent/EP0438345A1/en
Ceased legal-status Critical Current

Links

Images

Classifications

    • 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

Definitions

  • the invention relates to a collimator with thin blades.
  • a collimator essentially consists of parallel collimating plates having absorption properties of a radiation to be collimated and of a frame which holds these plates in place.
  • the blades are oriented in the direction of the radiation and delimit elongated section channels between which the radiation is divided.
  • the main problem that we seek to solve with this invention is to obtain a collimator whose outgoing radiation has a very low angular divergence.
  • a long collimator is indeed bulky and contributes to reducing the flux of transmitted radiation. Close-up blades reduce the transmitted light because more of the radiation is absorbed. Indeed, the section of all the blades becomes large compared to the total section of the collimator.
  • the concept on which the invention is based makes it possible to construct collimators of very low angular divergence and does not have the aforementioned drawbacks of loss of luminosity or flux or bulk.
  • the essential means used is the choice of blades of a material based on glass or silicon, which can be shaped into very thin blades without veiling, that is to say which remain rigid and undeformable. Such blades do not need to be tensioned, so that one can favorably build low-cost collimators by forming the frame with grooves in which the blades are held with play.
  • Such frames can be formed in practice of a stack of shims.
  • Another interesting solution consists, in the case of silicon blades, in forming them with flanges which are integral with them and whose stack forms the frame.
  • European patent 0 223 305 describes a device for regulating the section of a radiation by bent piezoelectric plates.
  • Another patent (US-A-4,739,173) uses blades sliding in a plane for this.
  • the parallel blades have the reference 1 and are arranged in a tight network between two plates 2 and 3 connecting the assembly which are joined by bolts 4 and pins 5.
  • the correct spacing between the blades 1 is held by a frame 6 formed of wedges 6 ′ (FIG. 2) stacked and compressed. In the appropriate places, these shims 6 ′ are provided with recesses to allow the passage of the screws 4 and the pins 5.
  • the radiation to be collimated is perpendicular to the plane of FIGS. 1 and 2.
  • the wedges 6 ′ are of uniform thickness but have in places smaller heights so as to form grooves 7 ( Figure 2) into which two opposite edges of the blades 1 are introduced.
  • the shims 6 ′ are preferably peelable shims made up of metallic strips glued and detached one by one by cleavage, with a knife, which make it possible to easily and precisely adjust the width of the grooves 7. This width is chosen so as to be slightly greater than the thickness of the blades 1.
  • the blades 1 are one tenth of a millimeter thick and the width of the grooves 7 is 0.125 mm.
  • the blades 1 therefore play in the grooves 7 and the collimator can be easily constructed, first by assembling the wedges 6 ′ and bolting them together, then by sliding the blades 1 in the grooves 7. It is understood that the replacement of 1 damaged blades will be just as easy.
  • the height of the blades 1 is 100 mm
  • the shims 6 ′ are 0.025 mm thick
  • the total height of the collimator is 130 mm
  • its length 200 mm its width of 50 mm
  • the total thickness of the frames 6 is 35 mm.
  • the interval between blades 1 can be chosen equal to 0.58 mm and the luminosity, that is to say the part of the cross-section of the collimator which is not occupied by the slats 1, is 85.3%.
  • the material used for the blades 1 can be glass or silicon charged with a body having absorption properties of the radiation which one seeks to collimate, that is to say boron or gadolinium for the neutrons. , or cadmium, TiB2, or lead for X and gamma rays.
  • This absorbent material can consist of charging particles embedded in the matrix of the base material or in a continuous surface deposit, for example gold in the case of silicon wafers.
  • FIG 3 shows another embodiment where the blades 8 are made of silicon and have opposite edges 9 and 10 rectilinear which are integral with them.
  • the flanges 9 and 10 can also be made of silicon or a material, such as copper, deposited on a smooth blade 8 at the start.
  • the collimator is assembled by stacking or superimposing the flanges 9 and 10 and then proceeding to assembly.
  • the assembly elements such as the screws 4 and the pins 5 pass through recesses in the flanges 9 and 10.
  • the blades 8 are not subjected to any mechanical stress.

Abstract

Collimator whose blades are based on glass or silicon, materials which make it possible to make the blades (1) very thin while remaining rigid, and this makes it possible to avoid their buckling and to bring them close together in order to obtain a very low angular divergence of the collimated radiation without excessively reducing its luminosity. The blades (1) are particularly easy to introduce and replace when their support is formed with grooves (7) into which the blades (1) are inserted with a clearance. <IMAGE>

Description

L'invention se rapporte à un collimateur à lames minces.The invention relates to a collimator with thin blades.

Un collimateur se compose essentiellement de lames de collimation parallèles présentant des propriétés d'absorption d'un rayonnement à collimater et d'une armature qui maintient en place ces lames. Les lames sont orientées dans la direction du rayonnement et délimitent des canaux à section allongée entre lesquels le rayonnement est divisé.A collimator essentially consists of parallel collimating plates having absorption properties of a radiation to be collimated and of a frame which holds these plates in place. The blades are oriented in the direction of the radiation and delimit elongated section channels between which the radiation is divided.

Le principal problème que l'on cherche à résoudre avec cette invention est l'obtention d'un collimateur dont le rayonnement sortant présente une très faible divergence angulaire. Deux moyens principaux peuvent permettre d'atteindre cet objectif: l'allongement du collimateur et le rapprochement des lames. Ces deux solutions impliquent toutefois des effets néfastes dans les dispositifs existants. Un collimateur long est en effet encombrant et contribue à réduire le flux de rayonnement transmis. Des lames rapprochées réduisent la luminosité transmise car une part plus importante du rayonnement est absorbée. En effet, la section de l'ensemble des lames devient importante par rapport à la section totale du collimateur.The main problem that we seek to solve with this invention is to obtain a collimator whose outgoing radiation has a very low angular divergence. There are two main ways of achieving this objective: lengthening the collimator and bringing the blades closer together. These two solutions, however, have harmful effects in existing systems. A long collimator is indeed bulky and contributes to reducing the flux of transmitted radiation. Close-up blades reduce the transmitted light because more of the radiation is absorbed. Indeed, the section of all the blades becomes large compared to the total section of the collimator.

Cette part pourrait être réduite en amincissant les lames mais on se heurte à des limites avec les systèmes existants, qui utilisent soit des lames de polymère tendues soit des lames métalliques. Les lames de polymère sont en effet fragiles et rapidement détruites sous un rayonnement à collimater, et cette solution présente en outre l'inconvénient d'être coûteuse aussi bien pour la fabrication que pour la réparation. Les lames métalliques quant à elles se voilent sous leur propre poids quand leur épaisseur est trop faible.This part could be reduced by thinning the blades, but there are limits to existing systems, which use either tensile polymer blades or metal blades. The polymer blades are indeed fragile and quickly destroyed under radiation to be collimated, and this solution also has the disadvantage of being expensive both for manufacturing and for repair. As for the metal blades, they veil under their own weight when their thickness is too thin.

Le concept sur lequel l'invention est fondée permet de construire des collimateurs de très faible divergence angulaire et ne présente pas les inconvénients mentionnés de perte de luminosité ou de flux ni d'encombrement. Le moyen essentiel utilisé est le choix de lames en un matériau à base de verre ou de silicium, qui peut être façonné en lames très minces sans se voiler, c'est-à-dire qui restent rigides et indéformables. De telles lames n'ont pas besoin d'être tendues, si bien qu'on peut favorablement construire des collimateurs de faible coût en formant l'armature avec des rainures dans lesquelles les lames sont maintenues avec du jeu. De telles armatures peuvent être constituées en pratique d'un empilement de cales. Une autre solution intéressante consiste, dans le cas de lames en silicium, à les former avec des rebords qui leur sont solidaires et dont l'empilement forme l'armature.The concept on which the invention is based makes it possible to construct collimators of very low angular divergence and does not have the aforementioned drawbacks of loss of luminosity or flux or bulk. The essential means used is the choice of blades of a material based on glass or silicon, which can be shaped into very thin blades without veiling, that is to say which remain rigid and undeformable. Such blades do not need to be tensioned, so that one can favorably build low-cost collimators by forming the frame with grooves in which the blades are held with play. Such frames can be formed in practice of a stack of shims. Another interesting solution consists, in the case of silicon blades, in forming them with flanges which are integral with them and whose stack forms the frame.

Le brevet européen 0 223 305 décrit un dispositif pour régler la section d'un rayonnement par des lames piézoélectriques fléchies. Un autre brevet (US-A-4 739 173) utilise pour cela des lames coulissant dans un plan.European patent 0 223 305 describes a device for regulating the section of a radiation by bent piezoelectric plates. Another patent (US-A-4,739,173) uses blades sliding in a plane for this.

L'invention va maintenant être décrite plus concrètement à l'aide des figures suivantes annexées à titre illustratif et non limitatif:

  • la figure 1 représente l'entrée d'un collimateur;
  • la figure 2 est une vue agrandie de la figure 1; et
  • la figure 3 représente schématiquement une autre réalisation possible.
The invention will now be described more concretely with the aid of the following figures, which are given by way of illustration and not limitation:
  • Figure 1 shows the input of a collimator;
  • Figure 2 is an enlarged view of Figure 1; and
  • FIG. 3 schematically represents another possible embodiment.

Sur la figure 1, les lames parallèles portent la référence 1 et sont disposées en un réseau serré entre deux plaques 2 et 3 de liaison de l'ensemble qui sont réunies par des boulons 4 et des goupilles 5. L'espacement correct entre les lames 1 est maintenu par une armature 6 formée de cales 6′ (figure 2) empilées et comprimées. Aux endroits appropriés, ces cales 6′ sont munies d'évidements pour permettre le passage des vis 4 et des goupilles 5. Le rayonnement à collimater est perpendiculaire au plan des figures 1 et 2.In Figure 1, the parallel blades have the reference 1 and are arranged in a tight network between two plates 2 and 3 connecting the assembly which are joined by bolts 4 and pins 5. The correct spacing between the blades 1 is held by a frame 6 formed of wedges 6 ′ (FIG. 2) stacked and compressed. In the appropriate places, these shims 6 ′ are provided with recesses to allow the passage of the screws 4 and the pins 5. The radiation to be collimated is perpendicular to the plane of FIGS. 1 and 2.

Les cales 6′ sont d'épaisseur uniforme mais présentent par endroits des hauteurs moins grandes de façon à constituer des rainures 7 (figure 2) dans lesquelles deux bords opposés des lames 1 sont introduits. Les cales 6′ sont de préférence des cales pelables constituées de lamelles métalliques collées et détachées une à une par clivage, au couteau, qui permettent de régler facilement et avec une grande précision la largeur des rainures 7. Cette largeur est choisie de façon à être un peu supérieure à l'épaisseur des lames 1. Dans une réalisation, les lames 1 ont un dixième de millimètre d'épaisseur et la largeur des rainures 7 est de 0,125 mm. Les lames 1 jouent donc dans les rainures 7 et le collimateur peut être construit facilement, d'abord en assemblant les cales 6′ et en les boulonnant entre elles, puis en glissant les lames 1 dans les rainures 7. On conçoit que le remplacement de lames 1 endommagées sera tout aussi facile. Dans la réalisation représentée, la hauteur des lames 1 est de 100 mm, la hauteur des rainures 7 de 100,5 mm, les cales 6′ ont 0,025 mm d'épaisseur, la hauteur totale du collimateur est de 130 mm, sa longueur de 200 mm, sa largeur de 50 mm et l'épaisseur totale des armatures 6 est de 35 mm. L'intervalle entre lames 1 peut être choisi égal à 0,58 mm et la luminosité, c'est-à-dire la part de la section du collimateur qui n'est pas occupée par les lames 1, est de 85,3 %.The wedges 6 ′ are of uniform thickness but have in places smaller heights so as to form grooves 7 (Figure 2) into which two opposite edges of the blades 1 are introduced. The shims 6 ′ are preferably peelable shims made up of metallic strips glued and detached one by one by cleavage, with a knife, which make it possible to easily and precisely adjust the width of the grooves 7. This width is chosen so as to be slightly greater than the thickness of the blades 1. In one embodiment, the blades 1 are one tenth of a millimeter thick and the width of the grooves 7 is 0.125 mm. The blades 1 therefore play in the grooves 7 and the collimator can be easily constructed, first by assembling the wedges 6 ′ and bolting them together, then by sliding the blades 1 in the grooves 7. It is understood that the replacement of 1 damaged blades will be just as easy. In the embodiment shown, the height of the blades 1 is 100 mm, the height of the grooves 7 of 100.5 mm, the shims 6 ′ are 0.025 mm thick, the total height of the collimator is 130 mm, its length 200 mm, its width of 50 mm and the total thickness of the frames 6 is 35 mm. The interval between blades 1 can be chosen equal to 0.58 mm and the luminosity, that is to say the part of the cross-section of the collimator which is not occupied by the slats 1, is 85.3%.

Le matériau utilisé pour les lames 1 peut être du verre ou du silicium chargé d'un corps présentant des propriétés d'absorption du rayonnement que l'on cherche à collimater, c'est-à-dire du bore ou du gadolinium pour les neutrons, ou encore du cadmium, du TiB₂, ou du plomb pour les rayons X et gamma.The material used for the blades 1 can be glass or silicon charged with a body having absorption properties of the radiation which one seeks to collimate, that is to say boron or gadolinium for the neutrons. , or cadmium, TiB₂, or lead for X and gamma rays.

Ce matériau absorbant peut consister en des particules de chargement noyées dans la matrice du matériau de base ou en un dépôt continu superficiel, par exemple d'or dans le cas de lames de silicium.This absorbent material can consist of charging particles embedded in the matrix of the base material or in a continuous surface deposit, for example gold in the case of silicon wafers.

La figure 3 représente une autre réalisation où les lames 8 sont en silicium et présentent des rebords opposés 9 et 10 rectilignes qui leur sont solidaires. Les rebords 9 et 10 peuvent être également en silicium ou en un matériau, tel que du cuivre, déposé sur une lame 8 lisse au départ. Le collimateur est assemblé en empilant ou superposant les rebords 9 et 10 puis en procédant à l'assemblage. Les éléments d'assemblages tels que les vis 4 et les goupilles 5 passent à travers des évidements des rebords 9 et 10. Comme dans le cas précédent, les lames 8 ne sont soumises à aucune contrainte mécanique.Figure 3 shows another embodiment where the blades 8 are made of silicon and have opposite edges 9 and 10 rectilinear which are integral with them. The flanges 9 and 10 can also be made of silicon or a material, such as copper, deposited on a smooth blade 8 at the start. The collimator is assembled by stacking or superimposing the flanges 9 and 10 and then proceeding to assembly. The assembly elements such as the screws 4 and the pins 5 pass through recesses in the flanges 9 and 10. As in the previous case, the blades 8 are not subjected to any mechanical stress.

Claims (4)

Collimateur constitué de lames parallèles (1, 8) présentant des propriétés d'absorption d'un rayonnement à collimater et d'une armature (6, 9, 10) maintenant en place les lames (1, 8), caractérisé en ce que les lames sont à base de verre ou de silicium et rigides.Collimator consisting of parallel blades (1, 8) having absorption properties of a radiation to be collimated and of a frame (6, 9, 10) holding the blades (1, 8) in place, characterized in that the blades are glass or silicon based and rigid. Collimateur suivant la revendication 1, caractérisé en ce que l'armature est formée avec des rainures (7) dans lesquelles les lames (1) sont maintenues avec du jeu.Collimator according to claim 1, characterized in that the frame is formed with grooves (7) in which the blades (1) are held with play. Collimateur suivant la revendication 2, caractérisé en ce que l'armature est constituée d'un empilement de cales.Collimator according to claim 2, characterized in that the armature consists of a stack of shims. Collimateur suivant la revendication 1, caractérisé en ce que l'armature est constituée d'un empilement de rebords (9, 10) solidaires des lames (8), les lames étant alors en silicium.Collimator according to claim 1, characterized in that the armature consists of a stack of flanges (9, 10) integral with the blades (8), the blades then being made of silicon.
EP91400075A 1990-01-17 1991-01-15 Thin blade collimator Ceased EP0438345A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9000491A FR2657192B1 (en) 1990-01-17 1990-01-17 THIN BLADE COLLIMATOR.
FR9000491 1990-01-17

Publications (1)

Publication Number Publication Date
EP0438345A1 true EP0438345A1 (en) 1991-07-24

Family

ID=9392847

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91400075A Ceased EP0438345A1 (en) 1990-01-17 1991-01-15 Thin blade collimator

Country Status (2)

Country Link
EP (1) EP0438345A1 (en)
FR (1) FR2657192B1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004012207A2 (en) * 2002-07-26 2004-02-05 Bede Plc Optical device for high energy radiation
WO2004012208A2 (en) * 2002-07-26 2004-02-05 Bede Plc Soller slit using low density materials
CN102949204A (en) * 2011-08-30 2013-03-06 苏州雷泰医疗科技有限公司 Grating blade for radiotherapy equipment

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL9300654A (en) * 1993-04-16 1994-11-16 Univ Delft Tech Grid to be called a slit pattern and a method for the manufacture thereof.

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0142841A2 (en) * 1983-11-18 1985-05-29 Kabushiki Kaisha Toshiba Aperture device of radiation diagnostic apparatus
EP0223305A1 (en) * 1985-11-15 1987-05-27 B.V. Optische Industrie "De Oude Delft" Piezoelectric attenuation tongue system for slit radiography equipment
US4739173A (en) * 1986-04-11 1988-04-19 Board Of Trustees Operating Michigan State University Collimator apparatus and method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0142841A2 (en) * 1983-11-18 1985-05-29 Kabushiki Kaisha Toshiba Aperture device of radiation diagnostic apparatus
EP0223305A1 (en) * 1985-11-15 1987-05-27 B.V. Optische Industrie "De Oude Delft" Piezoelectric attenuation tongue system for slit radiography equipment
US4739173A (en) * 1986-04-11 1988-04-19 Board Of Trustees Operating Michigan State University Collimator apparatus and method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004012207A2 (en) * 2002-07-26 2004-02-05 Bede Plc Optical device for high energy radiation
WO2004012208A2 (en) * 2002-07-26 2004-02-05 Bede Plc Soller slit using low density materials
WO2004012208A3 (en) * 2002-07-26 2004-06-03 Bede Plc Soller slit using low density materials
WO2004012207A3 (en) * 2002-07-26 2004-07-29 Bede Plc Optical device for high energy radiation
CN102949204A (en) * 2011-08-30 2013-03-06 苏州雷泰医疗科技有限公司 Grating blade for radiotherapy equipment

Also Published As

Publication number Publication date
FR2657192A1 (en) 1991-07-19
FR2657192B1 (en) 1993-11-05

Similar Documents

Publication Publication Date Title
EP0177104B1 (en) Device for coupling a light source and a light guide
EP0119128B1 (en) Head-up display
KR970003766B1 (en) Semiconductor laser module
EP1580763B1 (en) Rack arrangement for being incorporated in a container for the shipment of radioactive materials
US3772522A (en) Crystal monochromator and method of fabricating a diffraction crystal employed therein
FR2883384A1 (en) OPTICAL DEVICE FOR WAVELENGTH MULTIPLEXING
FR2664733A1 (en) LOWER NOZZLE OF A FUEL ASSEMBLY FOR NUCLEAR REACTOR COMPRISING AN ADAPTER PLATE AND A FILTRATION PLATE ATTACHED TO THE ADAPTER PLATE.
EP0438345A1 (en) Thin blade collimator
WO2021209434A1 (en) Apparatus for the spectral broadening of laser pulses and optical system
WO2013110785A1 (en) Device for attaching an optical member, attachment system and cryogenic device comprising such a device, method of manufacturing such a device and corresponding attachment method
FR2928138A1 (en) DEVICE FOR SUPPORTING AND FASTENING EQUIPMENT ON A PLATFORM NACELLA OR AIRCRAFT MOTOR.
EP0174671B1 (en) Scintillation camera for the detection of x or gamma rays, wherein an entrance window is made mechanically rigid and weakly absorbent to radiation
EP0018247B1 (en) Device for the stigmatic and achromatic magnetic deviation of a charged particles beam and irradiation apparatus using such a device
FR2765411A1 (en) SOLID LASER DEVICE WITH SEMICONDUCTOR EXCITATION
WO2009053453A2 (en) Device for holding nuclear fuel plates for a fissile bundle of a nuclear reactor of the gfr (gas fast reactor) type with high-temperature gaseous heat-carrier
FR2855276A1 (en) Anti-diffusion grid for X-ray apparatus has metallised layers with expanded polymer plate on at least one surface
DE102011120660A1 (en) Micro-mirror arrangement for wafer arrangement for e.g. laser projection, has static deflecting mirror for optical coupling of micro-mirrors, where deflecting mirror is bent regarding plane given by surface of substrate wafer
CA2165724C (en) Flexible coupling for rotating shafts
DE102009049228A1 (en) Device for concentrating and converting solar energy
EP1378917A1 (en) Rack arrangement for storing and/or transporting radioactive substances
EP0366562B1 (en) Detachable holding device for a piezoelectric resonator inside a housing
JP2004118049A (en) Optical path converting device
EP2828694B1 (en) System for injecting light into a waveguide, waveguide device and assembly for injecting light into a waveguide
FR2737745A3 (en) Assembly of building framework wooden pieces - consists in providing pieces along all height of their contact faces with interlocking tenons and mortises or dovetails
EP0352684A1 (en) Module for cilyndrical rigid membrane elements for separation, for filtration or catalytical transformation

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE GB SE

17P Request for examination filed

Effective date: 19911228

17Q First examination report despatched

Effective date: 19940630

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED

18R Application refused

Effective date: 19941224