EP0802559A1 - Flaches Bildschirm mit Wasserstoffquelle - Google Patents

Flaches Bildschirm mit Wasserstoffquelle Download PDF

Info

Publication number
EP0802559A1
EP0802559A1 EP97410044A EP97410044A EP0802559A1 EP 0802559 A1 EP0802559 A1 EP 0802559A1 EP 97410044 A EP97410044 A EP 97410044A EP 97410044 A EP97410044 A EP 97410044A EP 0802559 A1 EP0802559 A1 EP 0802559A1
Authority
EP
European Patent Office
Prior art keywords
hydrogen
source
screen
cathode
anode
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.)
Granted
Application number
EP97410044A
Other languages
English (en)
French (fr)
Other versions
EP0802559B1 (de
Inventor
Stéphane Mougin
Philippe Catania
Olivier Hamon
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.)
Pixtech SA
Original Assignee
Pixtech SA
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9491513&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0802559(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Pixtech SA filed Critical Pixtech SA
Publication of EP0802559A1 publication Critical patent/EP0802559A1/de
Application granted granted Critical
Publication of EP0802559B1 publication Critical patent/EP0802559B1/de
Anticipated expiration legal-status Critical
Revoked legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/86—Vessels; Containers; Vacuum locks
    • H01J29/88—Vessels; Containers; Vacuum locks provided with coatings on the walls thereof; Selection of materials for the coatings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/94—Selection of substances for gas fillings; Means for obtaining or maintaining the desired pressure within the tube, e.g. by gettering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2201/00—Electrodes common to discharge tubes
    • H01J2201/30—Cold cathodes
    • H01J2201/304—Field emission cathodes
    • H01J2201/30403—Field emission cathodes characterised by the emitter shape
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2329/00—Electron emission display panels, e.g. field emission display panels

Definitions

  • the present invention relates to flat display screens, and more particularly to cathodoluminescence screens, the anode of which carries luminescent elements, separated from each other by insulating zones, and liable to be excited by electronic bombardment from microtips.
  • the appended figure represents an example of a color microtip flat screen of the type to which the present invention relates.
  • Such a microtip screen essentially consists of a cathode 1 with microtips 2 and a grid 3 provided with holes 4 corresponding to the locations of the microtips 2.
  • the cathode 1 is placed opposite a cathodoluminescent anode 5 including a substrate of glass 6 constitutes the screen surface.
  • microtip screen The operating principle and a particular embodiment of a microtip screen are described, in particular, in American patent n ° 4,940,916 of the French Atomic Energy Commission.
  • the cathode 1 is organized in columns and consists, on a glass substrate 10, of cathode conductors organized in meshes from a conductive layer.
  • the microtips 2 are produced on a resistive layer 11 deposited on the cathode conductors and are arranged inside the meshes defined by the cathode conductors.
  • the figure partially represents the interior of a mesh and the cathode conductors do not appear in this figure.
  • the cathode 1 is associated with the grid 3 organized in lines. The intersection of a line of the grid 3 and a column of the cathode 1 defines a pixel.
  • This device uses the electric field which is created between the cathode 1 and the grid 3 so that electrons are extracted from the microtips 2. These electrons are then attracted by phosphor elements 7 from the anode 5 if these are suitably polarized.
  • the anode 5 is provided with alternating bands of phosphor elements 7r, 7g, 7b each corresponding to a color (Red, Green, Blue). The strips are parallel to the columns of the cathode and are separated from each other by an insulator 8, generally silicon oxide (SiO 2 ).
  • the phosphors 7 are deposited on electrodes 9, made up of corresponding strips of a transparent conductive layer such as indium tin oxide (ITO).
  • ITO indium tin oxide
  • the sets of red, green and blue bands are alternately polarized with respect to the cathode 1, so that electrons extracted from the microtips 2 of a pixel of the cathode / grid are alternately directed towards the phosphors 7 opposite each of the colors.
  • the command to select the phosphor 7 (the phosphor 7g in the figure) which must be bombarded by the electrons coming from the microdots of the cathode 1 requires to selectively control the polarization of the phosphor elements 7 of the anode 5, color by color .
  • the rows of the grid 3 are sequentially polarized at a potential of the order of 80 volts, while the strips of phosphor elements (for example 7g) to be excited are polarized under a voltage of the order of 400 volts via the ITO strip on which these phosphor elements are deposited.
  • ITO bands, carrying the other bands of phosphor elements (for example 7r and 7b) are at low or zero potential.
  • the columns of cathode 1 are brought to respective potentials between a maximum emission potential and a non-emission potential (for example, 0 and 30 volts respectively). The brightness of a color component of each of the pixels of a line is thus fixed.
  • the choice of the values of the polarization potentials is linked to the characteristics of the phosphors 7 and of the microtips 2. Conventionally, below a potential difference of 50 volts between the cathode and the grid, there is no electronic emission. , and the maximum emission used corresponds to a potential difference of 80 volts.
  • a disadvantage of conventional screens is that the microtips gradually lose their emissivity. This phenomenon can be seen by measuring the current in the cathode conductors. This results in a gradual decrease in the brightness of the screen, which adversely affects the life of conventional screens.
  • the present invention aims to overcome this drawback by making the emissive power of the microtips substantially constant.
  • the present invention also aims to propose a screen with automatic regulation of the emitting power of the microtips.
  • the present invention further aims to propose a method for producing a screen, the microtips of which have a substantially constant emissive power without modifying either the structure of the screen or the means of controlling the screen.
  • the present invention provides a flat display screen comprising a microtip cathode of electron bombardment of an anode provided with phosphor elements, the anode and the cathode being separated by a vacuum space, containing a source to gradual release of hydrogen.
  • the source of hydrogen consists of a thin layer deposit of a hydrogenated material.
  • the source of hydrogen consists of a resistive layer of the cathode on which the microtips are arranged.
  • the source of hydrogen consists of isolation bands separating bands of phosphor elements from the anode.
  • the source of hydrogen is produced on the periphery of the active area of the anode carrying the phosphors, a source of excitation of said source of hydrogen being produced, cathode side, opposite of said hydrogen source.
  • the present invention also provides a method of manufacturing a flat display screen, comprising the step of hydrogenating at least one of the constituent layers formed inside this screen.
  • the hydrogenated layer is obtained by chemical vapor deposition assisted by plasma from at least one precursor enriched in hydrogen.
  • the present invention originates from an interpretation of the phenomena which give rise to the abovementioned problems in conventional screens.
  • the inventors consider that these problems are due, in particular to an oxidation of the microdots of the cathode.
  • the surface layers of the anode are, from a chemical point of view, oxides, whether they are the phosphors 7 or the insulator 8.
  • the microtips are generally metallic , for example molybdenum (Mo).
  • the oxide layers tend to shrink under the effect of electron bombardment, i.e. to release oxygen which oxidizes the surface of the microtips which then lose their emissive power.
  • the present invention proposes to control this oxidation phenomenon of the cathode microtips by introducing into the inter-electrode space of the screen, a partial pressure of hydrogen.
  • the most negative potential consists of the metallic cathode material and the H + or H 2 + ions are therefore attracted by the microtips to reduce them if they are oxidized.
  • these H + or H 2 + ions are repelled by the anode and do not risk damaging the phosphor elements.
  • the water vapor (H 2 O) formed by the recombination of the H + or H 2 + ions is then trapped by an element for trapping impurities, generally called a "getter", communicating with the inter-electrode space.
  • a microtip screen is generally provided with an element for trapping impurities whose role is to absorb various pollutions resulting from the degassing of the layers of the screen in contact with the vacuum.
  • this getter does not succeed in effectively trapping the oxygen degassed by the phosphors 7 and the insulating layers 8 insofar as these degassings are carried out essentially in a positive ionic form (O 2 + ) which then finds itself attracted to the microtips before it can be trapped by the getter.
  • the water vapor obtained by the reduction of oxygen by hydrogen ions constitutes a neutral molecule which is then no longer attracted by the microtips and can be trapped by the getter.
  • the partial pressure of hydrogen should not, however, be too high so as not to affect the operation of the screen.
  • the presence of hydrogen in the vicinity of the microtips generates the formation of a microplasma of hydrogen in the vicinity of the microtips.
  • This plasma must remain at a sufficiently low pressure and be located around the tips to do not disturb the operation of the screen. In particular, if this plasma develops, there is a risk of an arc appearing between the anode and the cathode of the screen.
  • the partial pressure of hydrogen is according to the invention chosen as a function of the inter-electrode distance and the quality of the vacuum in the screen, in particular, of the partial pressure of the oxidizing species all combined.
  • a partial hydrogen pressure of 5.10 -4 millibars (5 10 -2 Pa) constitutes a limit pressure for an inter-electrode distance of approximately 0.2 min.
  • the partial pressure of hydrogen must be maintained at the chosen level even when the hydrogen is consumed and trapped by the getter.
  • a characteristic of the present invention is to provide, inside the inter-electrode space, a source of hydrogen which gradually releases H + ions as the screen operates, ie progressively degassing of oxidizing species from the anode.
  • this source is arranged near the tips, so that the released hydrogen is not trapped by the getter before reaching the microtips.
  • the source material must be able to release hydrogen only under excitation.
  • This excitation can be thermal. In this case, the temperature rise inside the screen during its operation causes a release of hydrogen. This excitation can also result from an electronic or ionic bombardment.
  • the hydrogen source is integrated in the insulating strips 8 which separate the strips of phosphor elements from the anode.
  • the activation of the hydrogen source takes place essentially by electron bombardment.
  • some electrons emitted by the microtips touch the edges of the insulating tracks.
  • the hydrogen source is produced on the cathode side and is for example integrated into the resistive layer which supports the microtips. The activation of the source is then thermal, the cathode not being bombarded.
  • a common advantage of the two embodiments described above is that they distribute the source of hydrogen over the entire surface of the screen and thus guarantee a homogeneous antioxidant effect in the screen.
  • Another advantage is that they allow automatic regulation of the partial pressure of hydrogen in the inter-electrode space, therefore of the antioxidant means of the microtips of the cathode. Indeed, the activation (thermal or by electron bombardment) of the hydrogen source is localized in the region of the microtips which emit and which are therefore liable to be oxidized.
  • Another advantage is that they do not require any modification of the structure of the screen, but only of the conditions of deposition of the insulating tracks 8 or of the resistive layer 11, as will be seen below.
  • the deposition parameters of at least one layer chosen are adjusted to cause the incorporation of hydrogen into the material of this layer.
  • the hydrogen diffusion incorporation is adjusted as a function of the quantity of hydrogen which it is desired to see released by the material during the operation of the screen, that is to say as a function of the quality of the vacuum in the inter-electrode space, in particular the partial pressure of the oxidizing species, and the excitation means chosen for the hydrogen source.
  • the hydrogen source consists of dedicated zones, arranged outside the active zone of the screen, for example, at the periphery of the anode. An excitation source is then produced on the cathode side opposite of these dedicated areas.
  • the excitation source may consist of a microtip zone opposite the hydrogen source outside the active zone of the screen.
  • the dedicated excitation source can be controlled at regular intervals to cause regeneration of the microtips. It can also be provided that this dedicated source is controlled from a measurement of the current flowing in the cathode conductors to cause a phase of regeneration of the microtips as a function of a current threshold from which it is considered desirable. to regenerate the microtips.
  • the various layers used in the manufacture of a screen are generally deposited by a plasma assisted chemical vapor deposition (PECVD).
  • PECVD plasma assisted chemical vapor deposition
  • Such a deposition method uses mixtures of precursor compounds of the material to be deposited. It is easy to control the content of hydrogen added to the precursors. This technique makes it possible to obtain highly hydrogenated deposits and to easily control the quantity of hydrogen by varying the deposition parameters (deposition temperature, self-biasing voltage, deposition pressure, annealing temperature, etc.).
  • the choice of material used depends, in particular, on the location of the hydrogen source.
  • the hydrogen source is produced on the cathode side, it will be possible to hydrogenate the silicon usually constituting the resistive layer 11 which dispenses hydrogen.
  • the hydrogen source consists of the insulating strips 8 between the strips of phosphor elements of the anode
  • a material will be chosen which is both dielectric and easily hydrogenable, for example, silicon carbide or silicon oxide.
  • silicon nitride which also has the advantage of minimizing the oxygen contained in the insulating strips so that the hydrogen released has the task of reducing the oxidizing species degassed essentially by the phosphor elements.
  • an amorphous compound When this is compatible with the role of the layer chosen to also constitute the source of hydrogen, an amorphous compound will preferably be chosen insofar as it can generate a large quantity of hydrogen since its concentration is not limited by a crystal structure.
  • the invention has been described above in relation to a color microtip screen, it also applies to a monochrome screen. If the anode of such a monochrome screen consists of two sets of alternating bands of phosphor elements, all the embodiments described above can be implemented. On the other hand, if the anode of the monochrome screen consists of a phosphor plane, the hydrogen source will be constituted either by a dedicated source external to the active area of the screen, or by the resistive layer on the cathode side. .

Landscapes

  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
  • Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
  • Electrodes For Cathode-Ray Tubes (AREA)
  • Cold Cathode And The Manufacture (AREA)
EP97410044A 1996-04-18 1997-04-15 Flacher Bildschirm mit Wasserstoffquelle Revoked EP0802559B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9605121 1996-04-18
FR9605121A FR2747839B1 (fr) 1996-04-18 1996-04-18 Ecran plat de visualisation a source d'hydrogene

Publications (2)

Publication Number Publication Date
EP0802559A1 true EP0802559A1 (de) 1997-10-22
EP0802559B1 EP0802559B1 (de) 2001-12-05

Family

ID=9491513

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97410044A Revoked EP0802559B1 (de) 1996-04-18 1997-04-15 Flacher Bildschirm mit Wasserstoffquelle

Country Status (5)

Country Link
US (1) US5907215A (de)
EP (1) EP0802559B1 (de)
JP (1) JPH1055770A (de)
DE (1) DE69708739T2 (de)
FR (1) FR2747839B1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0836217A1 (de) * 1996-10-14 1998-04-15 Hamamatsu Photonics K.K. Elektronenröhre
FR2781602A1 (fr) * 1998-07-21 2000-01-28 Futaba Denshi Kogyo Kk Dispositif electronique a cathode froide, et dispositif lumineux a emission de champ et dispositif lumineux a cathode froide comportant chacun celui-ci
WO2001089054A2 (en) * 2000-05-17 2001-11-22 Motorola, Inc. Field emission device having metal hydride source

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100288549B1 (ko) * 1997-08-13 2001-06-01 정선종 전계방출디스플레이
JP3481142B2 (ja) * 1998-07-07 2003-12-22 富士通株式会社 ガス放電表示デバイス
US20200357597A1 (en) * 2018-01-31 2020-11-12 Nano-X Imaging Ltd. Cold cathode x-ray tube and control method therefor

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR884289A (fr) * 1941-07-22 1943-08-09 Licentia Gmbh Tube de braun
US3432712A (en) * 1966-11-17 1969-03-11 Sylvania Electric Prod Cathode ray tube having a perforated electrode for releasing a selected gas sorbed therein
US3552818A (en) * 1966-11-17 1971-01-05 Sylvania Electric Prod Method for processing a cathode ray tube having improved life
DE2141145A1 (de) * 1971-08-12 1973-02-15 Energy Sciences Inc Verfahren und vorrichtung zum erzeugen von elektronen
US3945698A (en) * 1973-10-05 1976-03-23 Hitachi, Ltd. Method of stabilizing emitted electron beam in field emission electron gun
WO1996001492A1 (en) * 1994-07-01 1996-01-18 Saes Getters S.P.A. Method for creating and keeping a controlled atmosphere in a field emitter device by using a getter material

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2623013A1 (fr) * 1987-11-06 1989-05-12 Commissariat Energie Atomique Source d'electrons a cathodes emissives a micropointes et dispositif de visualisation par cathodoluminescence excitee par emission de champ,utilisant cette source
US5144191A (en) * 1991-06-12 1992-09-01 Mcnc Horizontal microelectronic field emission devices
JP3252545B2 (ja) * 1993-07-21 2002-02-04 ソニー株式会社 電界放出型カソードを用いたフラットディスプレイ
KR950034365A (ko) * 1994-05-24 1995-12-28 윌리엄 이. 힐러 평판 디스플레이의 애노드 플레이트 및 이의 제조 방법
US5714837A (en) * 1994-12-09 1998-02-03 Zurn; Shayne Matthew Vertical field emission devices and methods of fabrication with applications to flat panel displays
US5684356A (en) * 1996-03-29 1997-11-04 Texas Instruments Incorporated Hydrogen-rich, low dielectric constant gate insulator for field emission device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR884289A (fr) * 1941-07-22 1943-08-09 Licentia Gmbh Tube de braun
US3432712A (en) * 1966-11-17 1969-03-11 Sylvania Electric Prod Cathode ray tube having a perforated electrode for releasing a selected gas sorbed therein
US3552818A (en) * 1966-11-17 1971-01-05 Sylvania Electric Prod Method for processing a cathode ray tube having improved life
DE2141145A1 (de) * 1971-08-12 1973-02-15 Energy Sciences Inc Verfahren und vorrichtung zum erzeugen von elektronen
US3945698A (en) * 1973-10-05 1976-03-23 Hitachi, Ltd. Method of stabilizing emitted electron beam in field emission electron gun
WO1996001492A1 (en) * 1994-07-01 1996-01-18 Saes Getters S.P.A. Method for creating and keeping a controlled atmosphere in a field emitter device by using a getter material

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SCHWOEBEL P R ET AL: "FIELD-EMITTER ARRAY PERFORMANCE ENHANCEMENT USING HYDROGEN GLOW DISCHARGES", 5 July 1993, APPLIED PHYSICS LETTERS, VOL. 63, NR. 1, PAGE(S) 33 - 35, XP000382555 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0836217A1 (de) * 1996-10-14 1998-04-15 Hamamatsu Photonics K.K. Elektronenröhre
US5959400A (en) * 1996-10-14 1999-09-28 Hamamatsu Photonics K.K. Electron tube having a diamond field emitter
FR2781602A1 (fr) * 1998-07-21 2000-01-28 Futaba Denshi Kogyo Kk Dispositif electronique a cathode froide, et dispositif lumineux a emission de champ et dispositif lumineux a cathode froide comportant chacun celui-ci
WO2001089054A2 (en) * 2000-05-17 2001-11-22 Motorola, Inc. Field emission device having metal hydride source
WO2001089054A3 (en) * 2000-05-17 2002-03-28 Motorola Inc Field emission device having metal hydride source

Also Published As

Publication number Publication date
FR2747839B1 (fr) 1998-07-03
EP0802559B1 (de) 2001-12-05
DE69708739D1 (de) 2002-01-17
JPH1055770A (ja) 1998-02-24
FR2747839A1 (fr) 1997-10-24
US5907215A (en) 1999-05-25
DE69708739T2 (de) 2002-07-18

Similar Documents

Publication Publication Date Title
EP0558393A1 (de) Elektronenquelle mit Mikropunktkathoden und Anzeigevorrichtung mit Kathodolumineszenz erregt durch Feldemission unter Anwendung dieser Quelle
US5772485A (en) Method of making a hydrogen-rich, low dielectric constant gate insulator for field emission device
KR101000827B1 (ko) 전자방출소자 및 그것을 이용한 전자원 및 화상표시장치 및정보 표시 재생장치
FR2724940A1 (fr) Luminophore et dispositif d'affichage fluorescent
KR100618531B1 (ko) 전자방출소자, 전자원 및 다이폴층을 가진 화상표시장치
EP0802559B1 (de) Flacher Bildschirm mit Wasserstoffquelle
FR2760755A1 (fr) Luminophore et dispositif d'affichage
EP0893817B1 (de) Ionenpumpen eines flachen Mikrospitzen-Schirms
FR2803087A1 (fr) Cathode a emission par champ electrique, dispositif d'emission electronique et son procede de fabrication
EP0943153A1 (de) Ein durch einen mikrospitzen-träger beobachtbares, mit einer mikrospitzen-elektronenquelle versehenes bildschirm und verfahren zur herstellung dieser quelle
FR2748347A1 (fr) Anode d'ecran plat de visualisation a anneau de protection
EP0806787B1 (de) Herstellung einer Anode eines flachen Bildschirms
EP1200973B1 (de) Oxidkathode und zugehöriges herstellungsverfahren
FR2756418A1 (fr) Ecran plat de visualisation a deviation laterale
FR2798508A1 (fr) Dispositif permettant de produire un champ electrique module au niveau d'une electrode et son application aux ecrans plats a emission de champ
FR2765391A1 (fr) Dispositif d'affichage a cathodes a emission de champ
EP0877407A1 (de) Anode eines flachen Bildschirms
FR2784225A1 (fr) Source d'electrons a cathodes emissives comportant au moins une electrode de protection contre des emissions parasites
FR2797092A1 (fr) Procede de fabrication d'une anode d'un ecran plat de visualisation
FR2713823A1 (fr) Collecteur d'électrons comportant des bandes conductrices commandables indépendamment.
FR2809862A1 (fr) Ecran plat de visualisation a memoire d'adressage
FR2798507A1 (fr) Dispositif permettant de produire un champ electrique module au niveau d'une electrode et son application aux ecrans plats a emission de champ
CA2312845A1 (en) Self-gettering electron field emitter and fabrication process
KR20020057638A (ko) 전계방출형 표시소자 및 그 제조방법
FR2788879A1 (fr) Ecran a emission de champ equipe de microcanaux

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 FR GB IT

17P Request for examination filed

Effective date: 19980406

111Z Information provided on other rights and legal means of execution

Free format text: DE FR GB IT

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 20010205

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

REF Corresponds to:

Ref document number: 69708739

Country of ref document: DE

Date of ref document: 20020117

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20020314

PLBQ Unpublished change to opponent data

Free format text: ORIGINAL CODE: EPIDOS OPPO

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

PLBF Reply of patent proprietor to notice(s) of opposition

Free format text: ORIGINAL CODE: EPIDOS OBSO

26 Opposition filed

Opponent name: CANON INC.

Effective date: 20020905

29U Proceedings interrupted after grant according to rule 142 epc

Effective date: 20020621

29U Proceedings interrupted after grant according to rule 142 epc

Effective date: 20020906

29W Proceedings resumed after grant [after interruption of proceedings according to rule 142 epc]

Effective date: 20050502

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

Ref country code: GB

Payment date: 20050412

Year of fee payment: 9

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

Ref country code: FR

Payment date: 20050427

Year of fee payment: 9

Ref country code: DE

Payment date: 20050427

Year of fee payment: 9

PLAX Notice of opposition and request to file observation + time limit sent

Free format text: ORIGINAL CODE: EPIDOSNOBS2

PLBB Reply of patent proprietor to notice(s) of opposition received

Free format text: ORIGINAL CODE: EPIDOSNOBS3

RDAF Communication despatched that patent is revoked

Free format text: ORIGINAL CODE: EPIDOSNREV1

RDAG Patent revoked

Free format text: ORIGINAL CODE: 0009271

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

Free format text: STATUS: PATENT REVOKED

27W Patent revoked

Effective date: 20051202

GBPR Gb: patent revoked under art. 102 of the ep convention designating the uk as contracting state

Free format text: 20051202

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

Ref country code: IT

Payment date: 20060430

Year of fee payment: 10