EP0006267B1 - Method of manufacturing a channel plate structure - Google Patents

Method of manufacturing a channel plate structure Download PDF

Info

Publication number
EP0006267B1
EP0006267B1 EP19790200291 EP79200291A EP0006267B1 EP 0006267 B1 EP0006267 B1 EP 0006267B1 EP 19790200291 EP19790200291 EP 19790200291 EP 79200291 A EP79200291 A EP 79200291A EP 0006267 B1 EP0006267 B1 EP 0006267B1
Authority
EP
European Patent Office
Prior art keywords
dynode
separating elements
elements
sheets
dynodes
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
EP19790200291
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0006267A1 (en
Inventor
John Revere C/O Philips Electr. & Ass. Mansell
Alan George C/O Philips Electronic & Ass. Knapp
Henry Dermott C/O Philips Electronic & Ass. Stone
Colin Douglas Philips Electronic & Ass. Overall
Derek C/O Philips Electronic & Ass. Washington
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.)
Philips Electronics UK Ltd
Koninklijke Philips NV
Original Assignee
Philips Electronic and Associated Industries Ltd
Philips Electronics UK Ltd
Philips Gloeilampenfabrieken NV
Koninklijke Philips Electronics NV
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 Philips Electronic and Associated Industries Ltd, Philips Electronics UK Ltd, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Electronic and Associated Industries Ltd
Publication of EP0006267A1 publication Critical patent/EP0006267A1/en
Application granted granted Critical
Publication of EP0006267B1 publication Critical patent/EP0006267B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/04—Electron multipliers
    • H01J43/06—Electrode arrangements
    • H01J43/18—Electrode arrangements using essentially more than one dynode
    • H01J43/22—Dynodes consisting of electron-permeable material, e.g. foil, grid, tube, venetian blind
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/88—Mounting, supporting, spacing, or insulating of electrodes or of electrode assemblies

Definitions

  • the present invention relates to electron multipliers and more particularly to a method of manufacturing a channel plate structure which may be used in electronic imaging and display applications.
  • a channel plate is a secondary-emissive electron multiplier device which can be in the form of a glass plate having a first conductive layer on its input face and a separate second conductive layer on its output face to act respectively as input and output electrodes and a large number of channels with resistive walls passing through its thickness so that the electric field inside each channel varies uniformly along its length.
  • the multiplier device can also be in the form of a channel plate structure comprising a plurality of discrete dynode metal channel plates in a stack, each plate being separated from the others.
  • bonding separating elements of a low melting point glass are applied to the same surface of each channel plate as the spacing separating elements.
  • the plates are then arranged in a stack with the channels in the plates being aligned as desired and the stack is heated to a temperature to melt partly the low melting point glass bonding elements which bond themselves to the surface of an adjacent plate.
  • a secondary emissive material for example mild steel
  • the repeated heating of the plates in order to apply high melting point and low melting point glass separating elements to the plates and the heating to bond the elements to adjacent plates can affect adversely the secondary emissive material. This can have the effect that the channels do not behave uniformly over the area of the channel plate structure.
  • a method of manufacturing a channel plate structure comprising a stack of discrete, electrically conductive dynode plates each dynode plate being separated from an adjacent dynode plate by separating elements distributed across the area of the dynode plate, which elements are less conductive than the dynode plates, the method being characterised by applying a bonding medium to a surface of at least one of a plurality of perforate, electrically conductive dynode forming sheets, positioning separating elements in the form of individual entities on the surfaces to which the bonding medium has been applied, the separating elements being less conductive than the dynode forming sheets, effecting a bond between the separating elements and the surfaces to which the bonding medium has been applied so that the separating elements are substantially in contact with the surface of the dynode forming sheets to which the bonding medium has been applied, and arranging the sheets in a stack with the free surfaces of the separating elements contacting
  • the bonding medium comprises a glass enamel which is fired after being applied to the dynode forming sheets. Thereafter the separating elements are temporarily positioned on the enamelled surfaces and the separating elements are bonded to the enamelled surfaces by melting the glass enamel thereof.
  • the discrete separating elements may be spherical and comprise small glass spheres known as ballotini.
  • the provision of the discrete elements enables a greater consistency to be achieved in the electrical characteristics of the channel plate structure and in the spacing of adjacent channel plates, otherwise known as dynodes, from each other.
  • ballotini as insulating separators higher values of resistance and voltage breakdown limits between adjacent dynodes, compared with screen printed glass, are obtained.
  • laboratory-made channel plates having a working area of 150x200 mm 2 , a channel pitch of the order 0.8 mm and a spacer thickness of the order of 0.1 mm gave the following typical results:
  • Another advantage of using discrete elements as insulating or resistive separators is that their small size means that any electrons which drop-out in passing from one dynode to the next are unlikely to land on the elements causing a negative charge to build-up, which charge will oppose the passage of further electrons through the channels. Rather any drop-out electrons are likely to land on the dynode surface which is conducting and thereby they do not cause charging.
  • the separating elements should be resistive, that is be slightly conductive, rather than insulating
  • the elements, such as ballotini may be made a glass containing a high lead content which when heated in a reducing atmosphere of hydrogen causes a resistive surface to be produced thereon.
  • the resistive elements thus formed act as part of a resistor chain for biasing the dynodes.
  • the discrete separating elements may be arranged singly or in clusters as desired. Further they may be arranged more densely at the edge of each dynode than at the centre thereof. Such a distribution of the elements enables a greater bond strength to be given at the edges thereby minimising the risk of adjacent dynodes peeling apart and affecting adversely the uniformity in the performance of the channel plate structure.
  • the separating elements may be arranged regularly between the channels of each dynode and where the borders of the dynodes are imperforate, the density of the elements may be much greater.
  • the discrete separating elements may be bonded to adjacent dynodes and thereby form an integrated stack.
  • the elements may be bonded to one side of a plate forming a dynode and the channel plate structure is assembled by arranging the separated dynodes as a stack which is then clamped.
  • Figure 1 shows a channel plate structure 10 in which each of the dynodes 11, 12, 13 and 14 comprises a single, perforated metal plate.
  • Channels 15 in the dynodes 11 to 14 converge in the direction of electron multiplication and are aligned with each other.
  • the dynodes 11 to 14 are separated by spherical separating elements 16 in the form of ballotini which are bonded by glass enamel 17 to adjacent dynodes.
  • the density of the elements 16 at the imperforate edges of the dynodes 11 to 14 is greater than in the centre thereof.
  • the elements 16 are shown positioned between each channel opening of a dynode, they could be spaced apart by integral multiples of the distance between the centres of adjacent channels 15 of a dynode.
  • each dynode 16 be biassed separately by a power supply 18.
  • FIG 2 shows an alternative embodiment of a channel plate structure 10 to that shown in Figure 1.
  • Dynodes 20 to 23 each comprise two, juxtaposed, complementary perforated metal plates 25, 26 of which at least the channels 15 in the plate 26 of each dynode is secondary emissive as is illustrated diagrammatically by the electron multiplication of an electron beam incident in the channel of the dynode 21.
  • the separating elements 16 comprise ballotini arranged at suitable intervals between the channels.
  • Pairs of metal plates 25, 26, for example mild steel plates, having matching arrays of convergent apertures therein are cleaned.
  • a high yield secondary emissive surface is deposited by way of evaporation in the apertures of at least the plates 26.
  • the plates 25, 26 are then assembled to form dynodes with the smaller diameter openings of the apertures being arranged remote from each other.
  • each pair of part-dynodes are coated with a bonding medium which at a later stage, is used to bond the ballotini to the dynodes.
  • the bonding medium conveniently comprises a thin layer of glass enamel applied for example by screen printing or settling from a suspension. If the dynode material and the bonding medium have matching coefficients of expansion the bonding medium e.g. glass enamel may be applied all over the outer dynode surface, otherwise it should be applied locally in the form of dots which coincide with the subsequent positions of the ballotini to prevent the risk of the dynodes curling with temperature changes.
  • the enamel is fired to a glassy state, the temperature being typically in the range 350 to 450°C.
  • One of each adjacent pair of part-dynodes from adjacent dynodes is then coated with a sticky medium such as pine oil, the purpose of which is to hold the ballotini temporarily in place.
  • a stencil or the other dynode plate is then placed over the sticky medium and ballotini having for example a nominal diameter of 100 microns are brushed across the surface of the stencil.
  • the stencil consists of a thin sheet of perforated metal, the perforations being so located and of such a diameter that one glass sphere (or a cluster of a small number of ballotini if so desired) is placed at each of the required locations.
  • the stencil is removed leaving correctly located ballotini adhering to the part-dynode by means of the sticky medium.
  • the part-dynode is taken through a heating cycle to remove the sticky medium by volatilisation and to allow the glass layer to melt so that the ballotini are permanently bonded to the part-dynode.
  • the next step is to place an enamel coated part-dynode against a ballotini coated part-dynode in a jig which holds them in register whilst they are taken through a further heating cycle.
  • the temperature is raised until the enamel melts and the two part-dynodes become bonded with ballotini separating them. Care has to be exercised to ensure that the enamel does not cover the ballotini so as to cause a bridge to be formed between the two dynodes adversely affecting the insulation.
  • An alternative technique involves clamping the part-dynodes together instead of bonding them.
  • one part-dynode is coated with ballotini as described above.
  • the other part-dynode is not coated with enamel however, because. of the flexible nature of part-dynodes this method may only be adequate for multipliers with an area no greater than a few hundred cm2(for a part-dynode thickness of about 0.15 mm).
  • the bond between ballotini and a dynode is effected by a glass enamel.
  • glass is not the only suitable bonding medium, others may include potassium silicate solution, polyimide adhesive and Silvac (a proprietary vacuum-compatible adhesive).
  • Resistive separating elements can be provided by using ballotini made of lead- containing glass and reducing the surface of each sphere by heating in hydrogen. Where resistive elements are used, the dynodes need not be coupled separately to the power supply 18 as shown in Figures 1 and 2. Instead the power supply can be connected between the first and last dynode and the resistive elements act as a potential divider enabling each dynode to be bias as required.
  • Figure 3 diagrammatically illustrates a channel plate cathode ray tube 30 comprising a metal, for example mild steel, cone 31 having a substantially flat plate glass screen 32 closing the open end of the cone 31.
  • a channel plate 10 made in accordance with the present invention is disposed at a small distance, for example 10 mm, from the screen 32.
  • An electron gun 33 is disposed adjacent the closed end of the cone 31 and a deflection coil assembly 34 is disposed adjacent to, but spaced from, the electron gun 3 3 .
  • a low energy electron beam 35 from the electron gun 33 is deflected in raster fashion across the input side of the channel plate structure 10 by the coil assembly 34.
  • the beam undergoes electron multiplication in the structure 10 and the output electrons are applied substantially normally to the screen 32.
  • the channel plate structure may be placed like a shadow mask in a conventional cathode ray tube having a glass envelope.
  • channel plate structure described above may be used in other practical applications such as electron multipliers, image intensifier tubes, data display tubes, X-ray image intensifiers and certain types of gas discharge tubes.
  • the spherical elements conveniently comprise ballotini because they are readily available, the elements may be of any compatible material having a sufficiently high resistance greater than that of the dynodes and a melting point sufficiently high such that the elements will not be deformed during the normal processing of the channel plate assembly.
  • the discrete separating elements may have other shapes besides spherical, such as cylindrical, ellipsoidal prismatic and cubic. Irrespective of the precise shape of the elements, the technique for laying them down must ensure that they are in the desired positions and orientation so that the dynodes are separated by a substantially constant distance from each other.
EP19790200291 1978-06-14 1979-06-11 Method of manufacturing a channel plate structure Expired EP0006267B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB2687778 1978-06-14
GB7826877A GB2023332B (en) 1978-06-14 1978-06-14 Electron multipliers

Publications (2)

Publication Number Publication Date
EP0006267A1 EP0006267A1 (en) 1980-01-09
EP0006267B1 true EP0006267B1 (en) 1982-11-10

Family

ID=10497954

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19790200291 Expired EP0006267B1 (en) 1978-06-14 1979-06-11 Method of manufacturing a channel plate structure

Country Status (5)

Country Link
EP (1) EP0006267B1 (ja)
JP (1) JPS5516392A (ja)
CA (1) CA1139821A (ja)
DE (1) DE2964009D1 (ja)
GB (1) GB2023332B (ja)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2124017B (en) * 1982-06-16 1985-10-16 Philips Electronic Associated A deflection colour selection system for a single beam channel plate display tube
GB2129205A (en) * 1982-10-22 1984-05-10 Philips Electronic Associated Colour display tube
GB2138627A (en) * 1983-04-20 1984-10-24 Philips Electronic Associated Display apparatus
GB2154053A (en) * 1984-02-08 1985-08-29 Philips Electronic Associated High resolution channel multiplier dynodes
EP0204198B1 (de) * 1985-05-28 1988-10-05 Siemens Aktiengesellschaft Kanalstruktur eines Elektronenvervielfachers
GB2181319A (en) * 1985-10-04 1987-04-15 Philips Electronic Associated Colour display apparatus
GB2181677B (en) * 1985-10-21 1988-12-29 Philips Electronic Associated Method of making a colour selection deflection structure, and a colour picture display tube including a colour selection deflection structure made by the method
FR2608316B1 (fr) * 1986-12-12 1995-07-28 Radiotechnique Compelec Multiplicateur d'electrons du type a feuilles, a pont diviseur integre
GB2213632A (en) * 1987-12-11 1989-08-16 Philips Electronic Associated Flat cathode ray tube display apparatus
GB2215962A (en) * 1988-03-23 1989-09-27 Philips Electronic Associated Flat crt with stepped deflection and interlace
US5227691A (en) * 1989-05-24 1993-07-13 Matsushita Electric Industrial Co., Ltd. Flat tube display apparatus
JPH072165A (ja) * 1993-02-26 1995-01-06 Nkk Corp オイルタンカーの船体構造
US6380674B1 (en) 1998-07-01 2002-04-30 Kabushiki Kaisha Toshiba X-ray image detector
JP4246879B2 (ja) 2000-04-03 2009-04-02 浜松ホトニクス株式会社 電子増倍管及び光電子増倍管
JP4108905B2 (ja) * 2000-06-19 2008-06-25 浜松ホトニクス株式会社 ダイノードの製造方法及び構造
CN104269338B (zh) * 2014-09-17 2016-04-06 中国工程物理研究院激光聚变研究中心 用于光电成像和信号增强的变孔径微通道板及其制作方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1401969A (en) * 1971-11-17 1975-08-06 Mullard Ltd Electron multipliers
GB1402549A (en) * 1971-12-23 1975-08-13 Mullard Ltd Electron multipliers
GB1405256A (en) * 1972-04-20 1975-09-10 Mullard Ltd Electron multipliers
GB1434053A (en) * 1973-04-06 1976-04-28 Mullard Ltd Electron multipliers
GB1446774A (en) * 1973-04-19 1976-08-18 Mullard Ltd Electron beam devices incorporating electron multipliers
GB1431490A (en) * 1973-06-13 1976-04-07 Mullard Ltd Electron multipliers
GB1523730A (en) * 1974-12-13 1978-09-06 Mullard Ltd Secondaryemissive layers
GB1457213A (en) * 1975-01-30 1976-12-01 Mullard Ltd Electron multipliers

Also Published As

Publication number Publication date
JPS5516392A (en) 1980-02-05
GB2023332A (en) 1979-12-28
CA1139821A (en) 1983-01-18
DE2964009D1 (en) 1982-12-16
EP0006267A1 (en) 1980-01-09
GB2023332B (en) 1982-10-27
JPS6141097B2 (ja) 1986-09-12

Similar Documents

Publication Publication Date Title
EP0006267B1 (en) Method of manufacturing a channel plate structure
US4482836A (en) Electron multipliers
US3921022A (en) Field emitting device and method of making same
US2236041A (en) Electron discharge device
US4160311A (en) Method of manufacturing a cathode ray tube for displaying colored pictures
EP0025221A1 (en) Flat display device
US5705079A (en) Method for forming spacers in flat panel displays using photo-etching
US3914634A (en) Channel plate acting as discrete secondary-emissive dynodes
US2872721A (en) Electron image multiplier apparatus
EP0287139B1 (en) Channel plate electron multipliers
US4806827A (en) Multiplier element of the aperture plate type, and method of manufacture
US4270823A (en) Method of forming conductors in slots in a plate
US3182221A (en) Secondary emission multiplier structure
US3849692A (en) Surface conductive tilted channel plate electron multiplier
US4764139A (en) Production method for channel plate
EP0074738A2 (en) Method for making CRT shadow masks
JP2741418B2 (ja) メタルコアリブおよびその製造方法、並びに該メタルコアリブを用いたプラズマディスプレイパネル
US3803443A (en) Charged particle beam scanning device with electrostatic control
EP0081329B1 (en) Method of making a two mask structure for cathode ray tube
US7192327B2 (en) Image display device, method of manufacturing a spacer for use in the image display device, and image display device having spacers manufactured by the method
US4281270A (en) Precoated resistive lens structure for electron gun and method of fabrication
US2931914A (en) Electron multiplier mosaics
US4160310A (en) Metal-dielectric electron beam scanning stack
CA1074852A (en) Method of manufacturing a post-deflection focusing colour selection electrode
JPH04324231A (ja) 平面型表示装置

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): DE FR GB IT

17P Request for examination filed
ITF It: translation for a ep patent filed

Owner name: ING. C. GREGORJ S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 2964009

Country of ref document: DE

Date of ref document: 19821216

ET Fr: translation filed
GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19881118

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

Ref country code: FR

Payment date: 19910621

Year of fee payment: 13

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

Ref country code: DE

Payment date: 19910823

Year of fee payment: 13

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

Ref country code: FR

Effective date: 19930226

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

Ref country code: DE

Effective date: 19930302

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

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