EP0025374B1 - Wandler nicht-sichbarer in sichtbare Photone und Anlage zur zerstörungsfreien Prüfung unter Verwendung dieses Wandlers - Google Patents

Wandler nicht-sichbarer in sichtbare Photone und Anlage zur zerstörungsfreien Prüfung unter Verwendung dieses Wandlers Download PDF

Info

Publication number
EP0025374B1
EP0025374B1 EP80401179A EP80401179A EP0025374B1 EP 0025374 B1 EP0025374 B1 EP 0025374B1 EP 80401179 A EP80401179 A EP 80401179A EP 80401179 A EP80401179 A EP 80401179A EP 0025374 B1 EP0025374 B1 EP 0025374B1
Authority
EP
European Patent Office
Prior art keywords
photons
luminous
converter
radiation
source
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.)
Expired
Application number
EP80401179A
Other languages
English (en)
French (fr)
Other versions
EP0025374A1 (de
Inventor
Jean-Claude Michel Dufay
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.)
Laboratoire Central des Ponts et Chaussees
Original Assignee
Laboratoire Central des Ponts et Chaussees
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 Laboratoire Central des Ponts et Chaussees filed Critical Laboratoire Central des Ponts et Chaussees
Priority to AT80401179T priority Critical patent/ATE7087T1/de
Publication of EP0025374A1 publication Critical patent/EP0025374A1/de
Application granted granted Critical
Publication of EP0025374B1 publication Critical patent/EP0025374B1/de
Expired 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
    • G21K4/00—Conversion screens for the conversion of the spatial distribution of X-rays or particle radiation into visible images, e.g. fluoroscopic screens

Definitions

  • the present invention relates to a converter of non-luminous input photons such as X or ⁇ photons, into light photons intended to be associated with a system for optical transmission and reproduction of the image formed on the converter, this converter being of the type formed by an independent screen arranged on the path of said non-luminous photons and comprising a layer of phosphor.
  • the invention also relates to an installation for the non-destructive testing of material such as reinforced or prestressed concrete.
  • the radioscopy or gammascopy systems existing in the medical and industrial field use low and medium energy X-rays: most often from 10 keV to 200 keV. These systems generally give an image of insufficient brightness, requiring observation in a dark room.
  • a palliative known by an article from Iron & Steel, published in the August 1966 issue, p. 381-387 by Halmshaw et al consists in amplifying the image obtained on leaving the screen by electronic means.
  • the screen is an integral part of an image intensifier and is no longer independent. In both cases, we have relatively heavy, bulky and fragile equipment. This type of apparatus gives very good quality images only if the radiation used is of low or medium energy and only if the controlled material is of low density and not very diffusing.
  • this same apparatus does not give a satisfactory result if the radiation used is high energy X or y radiation (up to 10 MeV), the conversion efficiency of the intensifier then not being high enough, and if the controlled material is dense and very diffusing (case of concrete).
  • the present invention firstly aims to propose an independent screen converter having a satisfactory efficiency for input photons of energy greater than 200 keV, by giving a satisfactory image which can be directly observed.
  • the present invention also aims to associate with the converter a non-destructive inspection installation by radioscopy or gamma-ray imaging giving good quality images on concrete thicknesses as large as possible, while being able to use the same sources of radiation as conventional radiography (Ir 192 and Cobalt 60).
  • radioscopy or gamma-ray imaging giving good quality images on concrete thicknesses as large as possible, while being able to use the same sources of radiation as conventional radiography (Ir 192 and Cobalt 60).
  • conventional radiography Ir 192 and Cobalt 60
  • the proposed device being intended for use on site, care should be taken to select components of low weight, small dimensions and very good mechanical strength, with the minimum of servitudes as to the electrical supplies necessary for its operation.
  • the converter according to the invention is characterized in that it comprises, from upstream to downstream, relative to the direction of movement of the non-luminous photons of entry, a light support, a metallic sheet in which said non-luminous photons are converted in non-luminous photons of lower energy, by Compton collision of said high energy photons on electrons of said metallic sheet, a thin layer reflecting light in titanium oxide, and the lumiphore layer.
  • the document FR-A-2345806 already discloses an image intensifier intended to be used with high energy radiation, associating with a layer of luminescent substance, a metal sheet in which the non-luminous photons input are converted into non-luminous photons of lower energy by Compton effect.
  • this intensifier is in the form of a glass vacuum tube, the fragility and size of which make use on site problematic.
  • the energy of the non-luminous input photons is substantially between 200 keV and 10 MeV.
  • the thickness of the metal sheet is between 100 and 500 k tm.
  • the metal sheet comprises at least one of the following metals: lead, gold.
  • the non-destructive testing installation is characterized in that it comprises: a source of non-luminous photonic radiation directing a flow of said radiation on the material to be checked, a lead filter disposed downstream of this material for stop low energy radiation from the scattering in said material of radiation from the source, a converter as described above, to transform the photons from said filter into light photons, a mirror inclined relative to the path of said light photons to receiving these photons and directing them onto the input objective of a television camera, and an image viewing device receiving the video signal supplied by said camera.
  • the source, on the one hand, and the detection assembly comprising the converter, the mirror and the television camera, on the other hand, are each associated with respective displacement means for moving them in at least two directions. spatial, these displacement means being remotely controllable.
  • the installation shown includes: a source of X or ⁇ radiation, 1 directing a beam of high energy radiation 2 towards a reinforced concrete or prestressed concrete to be inspected 3, a lead filter 4 stopping the low energy radiation from the scattering in the material 3 of the radiation 2 coming from the source 1, a converter 5 transforming the X or y photons coming from the filter 4 into light photons 6 forming an image of suitable format, for example of 30 cm x 40 cm, a mirror 7 disposed at 45 ° relative to the plane 5a of the converter 5, this mirror receiving the light 6 supplied by the converter 5 and having a high reflection coefficient, for example 0.97, for the emission wavelength of the converter 5, a television camera 8 analyzing line by line the image reflected by the mirror 7, this camera 8 preferably being at low light level, and being equipped with an optical objective 8a of high brightness and large aperture , for example open rant at f / 0.95, and a display device - or monitor - 9 displaying the image obtained from the video signal which is supplied by the camera 8 and
  • the radiation supplied by the source 1 is preferably of energy between 200 keV and 10 MeV.
  • This source 1 can be a Cobalt 60 or Iridium 192 source; alternatively, this source can be of the type comprising an accelerator directing a flow of electrically charged particles on a target.
  • Known y-visible or X-visible converters generally have a very low efficiency - or yield - as soon as the energy of the photons X or y exceeds 200 keV. It was therefore excluded to use one of these converters in the inspection and / or control installation presently described.
  • the converter represented in FIG. 2 has the advantage of giving, from high energy X or y photons, an image of sufficient quality for the search for defects in concrete.
  • a converter is not fragile, it is simple to use and, in particular, it does not require complicated electronic equipment, and it is thin, light, and available - or easy to make - in dimensions identical to those of commonly used x-ray films: 30 cm x 40 cm.
  • This converter comprises contiguously and from left to right in FIG. 2: a cardboard support 13, a metallic sheet of lead or gold, 14 of approximately 250 ⁇ m thick, arranged on one face of said support 13, a reflective layer of titanium oxide Ti0 2 , 15, of approximately 10 ⁇ m thick, a fluorescent layer of Zn SCd: Ag, 16 of approximately 1000 ⁇ m thick and a protective layer 17 of approximately 10 ⁇ .Lm thick.
  • the photons ⁇ or X - from the material to be checked 3 are transformed into visible light by the converter 5: the image thus formed on this converter is taken up by the mirror 7 with a high reflection coefficient (0.97), for the length emission wave of the converter 5, and analyzed by the television camera at low light level 8.
  • the video signal coming from the camera 8 forms, at a distance, the image sought on the television screen 9.
  • This image can be recorded either on the video recorder 11, for later examination, or on the graphic video image recorder 12 for archiving or insertion in a folder.
  • the quality of the image obtained can be improved at the output of the camera 8 by the storage-integration unit 10 (improvement of the signal / noise ratio, that is to say of the contrast).
  • This type of screen converter typically has a 12.8% improvement in brightness, compared to a known medical fluorescent screen used under the same conditions. The contrast is increased by 12%. Other measurements have also shown that the brightness of this screen is produced mainly by the primary radiation coming from the material to be checked, whereas in the case of the known medical screen, this luminosity is mainly due to the scattered radiation.
  • the limit resolution of the complete chain in Figure 1 is that of the converter, i.e. 1 ⁇ l / mm at 4% contrast.
  • the so-called televised radioscopy chain thus formed typically gives perfectly usable images up to a thickness of concrete traversed by 45 cm for a Cobalt 60 source of 250 Ci, and 1 m thick for a linear accelerator delivering 700 rad / min at 1 m at 10 MeV.
  • This televised radioscopy chain is advantageously applied to the control of the quality of concrete injections and to the positioning of prestressed cables in concrete.
  • the source 1 and the detector assembly 4 and 5, 7 and 8, designated below under the reference 19 must move in synchronism on either side of the concrete wall 30 to be inspected. This will be achieved by “piloting on sight of the assembly according to the principle of FIG. 3.
  • the source 1 and the detection sub-assembly 19 are each associated with means, respectively 20 and 21, for their displacement in X, and Z or in X, Y and Z; the means 20 and 21 are each remotely controlled by a respective manual control device 22 and 23.
  • Figures 4 box bridge
  • 5 beam bridge
  • 6 slab bridge
  • the source 1 is preferably a linear accelerator
  • Figures 3 to 6 the same elements are designated by the same references.
  • Figure 6 shows, on its right and left halves, two modes of arrangement of the inspection chain.
  • the displacement means 20 and 21 are mechanically independent from one another, while, according to FIG. 5, these means are joined together by a structural element 24. According to FIG. 6, a single displacement means 20 ensures the displacement of the units 1 and 19.
  • the so-called high-energy televised radioscopy installation which has just been described is mainly intended for the control of prestressed concrete engineering structures, using high energy X or y radiation (preferably from 200 keV to 10 MeV). It implements a special fluometallic converter specially designed and manufactured for this installation.
  • the televised radioscopy chain described can also find its application whenever an almost instantaneous visualization of defects existing in a more or less dense material is necessary, from X or ⁇ radiation of high energy (for example in industry building, wood, metallurgy, etc.) and where a limit resolution of 1 pl / mm at 4% contrast is sufficient.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
  • Led Devices (AREA)
  • Conversion Of X-Rays Into Visible Images (AREA)
  • Measurement Of Radiation (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)

Claims (9)

1. Umwandler von nicht sichtbaren Photonen, sogenannten Eintrittsphotonen, wie Röntgen-oder -y-Photonen, in sichtbare Photonen, zur Eingliederung in ein System für die optische Übertragung und Wiedergabe des über den Umwandler entstandenen Bildes, welcher Umwandler durch einen unabhängigen, in der Bahn der nicht sichtbaren Photonen angeordneten und eine Luminophorschicht (16) aufweisenden Bildschirm gebildet ist, dadurch gekennzeichnet, daß er, in der Bewegungsrichtung der nicht sichtbaren Eintrittsphotonen gesehen, von strahlaufwärts nach strahlabwärts einen leichten Träger (13), eine Metallfolie (14), in welcher diese nicht sichtbaren Photonen durch Compton-Zusammenstoß dieser Eintrittsphotonen mit den Elektronen der Metallfolie in nicht sichtbare Photonen von niedrigerer Energie umgewandelt werden, eine dünne lichtreflektierende Schicht (15) aus Titanoxid und die Luminophorschicht (16) umfaßt.
2. Umwandler nach Anspruch 1, dadurch gekennzeichnet, daß der Träger (13) aus Karton besteht.
3. Umwandler nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, daß die Energie der nicht sichtbaren Eintrittsphotonen im wesentlichen zwischen 200 keV und 10 MeV beträgt.
4. Umwandler nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Dicke der Metallfolie (14) zwischen 100 und 500 µm beträgt.
5. Umwandler nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß die Metallfolie (14) zumindest eines der folgenden Metalle umfaßt : Blei, Gold.
6. Umwandler nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die Luminophorschicht (16) aus Zn S Cd : Ag von einer Dicke zwischen 600 und 1 500 ¡.Lm, vorzugsweise etwa 1 000 µm ist.
7. Vorrichtung zur nicht destruktiven Werkstoffprüfung unter Anwendung eines Umwandlers nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß sie eine Quelle (1) für nicht sichtbare Photonenstrahlung umfaßt, die einen Strom dieser Strahlung (2) auf den zu prüfenden Werkstoff (3, 30, 31, 32, 33) richtet, einen strahlabwärts dieses Werkstoffs befindlichen Bleifilter (4) zum Auffangen der Strahlung niedriger Energie, die von der Diffusion der von der Quelle (1) ausgesandten Strahlung (2) im Werkstoff herrührt, den Umwandler (5) zum Umwandeln der vom Filter ausgehenden Photonen in sichtbare Photonen (6), einen in bezug auf die Bahn der sichtbaren Photonen (6) geneigten Spiegel (7) zum Auffangen und Lenken dieser Photonen auf ein Eingangsobjektiv (8a) einer Fernsehkamera (8) und eine das von der Kamera (8) abgegebene Videosignal empfangende Bildanzeigeeinrichtung (9).
8. Vorrichtung nach Anspruch 7, weiters dadurch gekennzeichnet, daß die Quelle (1) zumindest eine der folgenden radioaktiven Substanzen enthält : Iridium 192 und Kobalt 60.
9. Vorrichtung nach einem der Ansprüche 7 oder 8, weiters dadurch gekennzeichnet, daß die Quelle (1) einerseits und die Detektionseinheit (19) aus Umwandler (5), Spiegel (7) und Fernsehkamera (8) anderseits jeweils mit Bewegungsmitteln (20, 21) zum Verschieben derselben in zumindest zwei räumliche Richtungen verbunden sind, welche Bewegungsmittel fernsteuerbar sind.
EP80401179A 1979-08-14 1980-08-12 Wandler nicht-sichbarer in sichtbare Photone und Anlage zur zerstörungsfreien Prüfung unter Verwendung dieses Wandlers Expired EP0025374B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT80401179T ATE7087T1 (de) 1979-08-14 1980-08-12 Wandler nicht-sichbarer in sichtbare photone und anlage zur zerstoerungsfreien pruefung unter verwendung dieses wandlers.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7920708A FR2463420A1 (fr) 1979-08-14 1979-08-14 Convertisseur de photons non lumineux en photons lumineux et installation de controle non destructif faisant application de ce convertisseur
FR7920708 1979-08-14

Publications (2)

Publication Number Publication Date
EP0025374A1 EP0025374A1 (de) 1981-03-18
EP0025374B1 true EP0025374B1 (de) 1984-04-11

Family

ID=9228848

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80401179A Expired EP0025374B1 (de) 1979-08-14 1980-08-12 Wandler nicht-sichbarer in sichtbare Photone und Anlage zur zerstörungsfreien Prüfung unter Verwendung dieses Wandlers

Country Status (8)

Country Link
US (1) US4398093A (de)
EP (1) EP0025374B1 (de)
JP (1) JPS56155900A (de)
AT (1) ATE7087T1 (de)
CA (1) CA1171559A (de)
DE (1) DE3067443D1 (de)
ES (1) ES8106210A1 (de)
FR (1) FR2463420A1 (de)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58122500A (ja) * 1982-01-14 1983-07-21 富士写真フイルム株式会社 放射線像変換パネル
JPS59148853A (ja) * 1983-02-14 1984-08-25 Kansai Electric Power Co Inc:The コンクリ−ト製品等の非破壊検査方法
NL8900040A (nl) * 1989-01-09 1990-08-01 Philips Nv Roentgenbeeldversterkerbuis met selectief filter.
JP3741613B2 (ja) * 2001-01-29 2006-02-01 株式会社光子発生技術研究所 高エネルギーｘ線イメージング装置およびその方法

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB805802A (en) * 1955-09-26 1958-12-10 Gen Electric Improvements relating to radiant energy image intensifier systems
US3163765A (en) * 1961-06-14 1964-12-29 Rauland Corp Gamma ray image converters
US3356851A (en) * 1963-10-22 1967-12-05 Picker X Ray Corp Division Inc Image intensifier tube with separable optical coupler
DE1439344A1 (de) * 1964-03-11 1969-02-13 Siemens Ag Bildwandler
FR1496819A (fr) * 1966-08-25 1967-10-06 Automatisme Cie Gle Dispositif permettant d'obtenir un faisceau de rayonnement d'énergie réglable à partir d'un faisceau de rayonnement d'énergie constante
BE792387A (nl) * 1971-12-31 1973-06-07 Agfa Gevaert Nv Versterkingsschermen voor rontgenfotografie
US3758723A (en) * 1972-01-18 1973-09-11 Imagex Inc X-ray inspection system
JPS5210037A (en) * 1975-07-15 1977-01-26 Fujitsu Ltd Shift register circuit
FR2345806A1 (fr) * 1976-03-24 1977-10-21 Rolls Royce Perfectionnements apportes aux intensificateurs d'image
US4195228A (en) * 1978-05-19 1980-03-25 General Electric Company Color contrast radiographic device
US4256965A (en) * 1979-01-15 1981-03-17 The United States Of America As Represented By The Secretary Of The Navy High energy fluoroscopic screen
DE2927428C3 (de) * 1979-07-06 1982-05-19 Siemens AG, 1000 Berlin und 8000 München Leuchtstoff

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Article de HALMSHAW et al. Publié dans la revue GB, IRON and STEEL, août 1966, pages 381-387 *

Also Published As

Publication number Publication date
JPS56155900A (en) 1981-12-02
DE3067443D1 (en) 1984-05-17
CA1171559A (fr) 1984-07-24
FR2463420A1 (fr) 1981-02-20
FR2463420B1 (de) 1982-11-12
ES494236A0 (es) 1981-07-16
ES8106210A1 (es) 1981-07-16
ATE7087T1 (de) 1984-04-15
US4398093A (en) 1983-08-09
EP0025374A1 (de) 1981-03-18

Similar Documents

Publication Publication Date Title
JP4800434B2 (ja) シンチレータパネル、放射線イメージセンサの製造方法
EP1004039B1 (de) Bildgebendes verfahren und system unter verwendung von gamma- und röntgenstrahlung
US6455860B1 (en) Resolution enhancement device for an optically-coupled image sensor using high extra-mural absorbent fiber
EP2549298B1 (de) Großformatiger Szintillator für Bildanzeigevorrichtung, Szintillatormodul und Herstellungsverfahren eines Szintillators
FR2883074A1 (fr) Systeme de detection bidimensionnelle pour rayonnement neutrons
FR2668612A1 (fr) Dispositif d'imagerie de radiations ionisantes.
FR2700210A1 (fr) Dispositif de détection simultanée et sélective de neutrons et de photons X ou gamma et système de détection utilisant ce dispositif.
US6091796A (en) Scintillator based microscope
WO2008012417A2 (fr) Procede de caracterisation non destructif, notamment pour les particules de combustible nucleaire pour reacteur a haute temperature
EP0025374B1 (de) Wandler nicht-sichbarer in sichtbare Photone und Anlage zur zerstörungsfreien Prüfung unter Verwendung dieses Wandlers
EP0403802B1 (de) Röntgenbildverstärker und Verfahren zur Herstellung des Eingangsschirmes
US5401964A (en) Reduced electron scattering phosphor screen for high resolution transmission electron microscope imaging
US4052621A (en) Object viewing system with radiation responsive screen system
Labate et al. Novel x-ray multispectral imaging of ultraintense laser plasmas by a single-photon charge coupled device based pinhole camera
FR2623659A1 (fr) Tube intensificateur d'images a rayons x
CA3061418A1 (fr) Detecteur pour radiographie a haute energie et ensemble d'imagerie associe
FR2521781A1 (fr) Convertisseur d'images radiologiques
EP1014078A2 (de) Röntgenuntersuchung eines Objektes mit einem Kristallgitter
EP0533538B1 (de) Bildverstärkerröhre mit Helligkeitskorrektur
FR2659746A1 (fr) Detecteur a corps solide de rayonnement a multiples energies.
FR2559912A1 (fr) Procede et appareil de mesure d'un rayonnement gamma
FR2555321A1 (fr) Dispositif de detection de rayonnements x a scintillation
FR2698482A1 (fr) Dispositif générateur d'images par effet de luminescence.
FR2822294A1 (fr) Ecran de conversion de rayonnement x en photons lumineux
CH691006A5 (fr) Procédé, détecteur et dispositif d'imagerie radiographique utilisant des faisceaux de rayons gamma et rayon X appliqués au traitement radiothérapique et au contrôle non-destructif.

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

Designated state(s): AT BE CH DE GB IT LU NL SE

17P Request for examination filed

Effective date: 19810410

ITF It: translation for a ep patent filed

Owner name: JACOBACCI & PERANI S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): AT BE CH DE GB IT LI LU NL SE

REF Corresponds to:

Ref document number: 7087

Country of ref document: AT

Date of ref document: 19840415

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3067443

Country of ref document: DE

Date of ref document: 19840517

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
ITTA It: last paid annual fee
EPTA Lu: last paid annual fee
EAL Se: european patent in force in sweden

Ref document number: 80401179.9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19980723

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19980728

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19980804

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19980811

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 19980817

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19980818

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: LU

Payment date: 19980821

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19980911

Year of fee payment: 19

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990812

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990812

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990812

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19990830

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990831

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990831

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990831

BERE Be: lapsed

Owner name: ETAT FRANCAIS REPRESENTE PAR LE MINISTERE DE L'EN

Effective date: 19990831

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000301

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19990812

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

EUG Se: european patent has lapsed

Ref document number: 80401179.9

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20000301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000601