EP0275769A1 - Photoelektronischer Umwandler mit einer aus mehreren Mikrospitzen bestehenden Emissionskathode - Google Patents

Photoelektronischer Umwandler mit einer aus mehreren Mikrospitzen bestehenden Emissionskathode Download PDF

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Publication number
EP0275769A1
EP0275769A1 EP87402918A EP87402918A EP0275769A1 EP 0275769 A1 EP0275769 A1 EP 0275769A1 EP 87402918 A EP87402918 A EP 87402918A EP 87402918 A EP87402918 A EP 87402918A EP 0275769 A1 EP0275769 A1 EP 0275769A1
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EP
European Patent Office
Prior art keywords
electrode
light
electrodes
layer
transducer according
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
EP87402918A
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English (en)
French (fr)
Inventor
Robert Baptist
Michel Borel
Ariel Brenac
Robert Meyer
Gérard Chauvet
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
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Commissariat a lEnergie Atomique CEA
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Filing date
Publication date
Application filed by Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Publication of EP0275769A1 publication Critical patent/EP0275769A1/de
Ceased legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
    • H01J31/26—Image pick-up tubes having an input of visible light and electric output
    • 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
    • H01J1/02—Main electrodes
    • H01J1/34—Photo-emissive cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
    • H01J31/49—Pick-up adapted for an input of electromagnetic radiation other than visible light and having an electric output, e.g. for an input of X-rays, for an input of infrared radiation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2201/00—Electrodes common to discharge tubes
    • H01J2201/34—Photoemissive electrodes
    • H01J2201/342—Cathodes
    • H01J2201/3421—Composition of the emitting surface
    • H01J2201/3423—Semiconductors, e.g. GaAs, NEA emitters

Definitions

  • the present invention relates to a photoelectronic transducer using a microtip emissive cathode.
  • Emissive microdot cathodes are already known by US Patent 3,755,704, US Patent 3,921,022, FR-A-2443085 and the French patent application No. 8411986 of 27 July 1984 (or the request to USA No. 758 737 of 25 July 1985) for example.
  • the present invention relates to a photoelectronic transducer using this surprising effect.
  • Photoelectronic transducers are already known, but these generate weak electric currents which must therefore be amplified in order to be able to process them (for example digitize them).
  • the object of the present invention is to remedy this drawback by proposing a photoelectronic transducer which is capable of producing large variations in electric current, from electric currents of large intensities, currents which are thus easy to process.
  • the invention can for example make it possible to obtain variations of + 100 microamps from currents of 100 microamps.
  • the subject of the present invention is a photoelectronic transducer, characterized in that it comprises: - at least one first electrode which is made of a material whose conductivity increases when it is illuminated by a determined light and of which one face is provided with a plurality of microtips which are made of an electron emitting material and whose bases are on said face, at least one second electrode, this second electrode being electrically isolated from the first electrode, disposed opposite said face and pierced with holes situated respectively opposite said bases, the apex of each microtip being situated at the level of the hole which corresponds to it, - At least a third electrode, this third electrode being disposed opposite the second electrode and being electrically isolated from the latter which is thus between the first and the third electrodes, so that electrons are emitted by the microtips and collected by the third electrode when the microtips and the first, second and third electrodes are in a vacuum, that the second electrode is positively polarized with respect to the first electrode and that the third electrode is positively polarized with respect
  • Said light can be chosen in the field of visible or X-ray radiation, for a material with a first electrode such as p-doped silicon for example.
  • the present invention applies in particular to the production of presence detectors, photocopiers, very flat video cameras, X cameras and X-ray detectors.
  • a layer of an electrically insulating material capable of transmitting at least part of said light is placed between the first and second electrodes, at least part of the layer not being covered by the second electrode, so as to be able to detect said increase when said light is sent towards said part of the layer.
  • the third electrode is capable of transmitting at least part of said light so as to be able to detect said increase when said light is sent in the direction of said third electrode.
  • a layer of an electrically insulating material capable of transmitting at least part of said light can be placed between the first and second electrodes.
  • the transducer is arranged so that the other face of the first electrode is reached by said light.
  • a transducer according to the invention can be produced, comprising a single first electrode and a single second electrode, but it is also possible to produce a transducer according to the invention, comprising a matrix structure with several first electrodes and several second electrodes: according to one embodiment particular of the transducer which is the subject of the invention, the latter comprises several parallel and elongated copies of said first electrode and several parallel and elongated copies of said second electrode, the first electrodes make an angle with the second electrodes, which defines crossing zones of the first and second electrodes, the microtips and the holes are located in these crossing zones and the detection means are provided for detecting the currents corresponding respectively to the crossing zones.
  • this transducer according to the invention and with a matrix structure further comprises control means provided for performing a matrix addressing of the first and second electrodes, the third the electrode being unique, so that the crossing zones can successively emit electrons, and the detection means are provided for detecting the current relating to each of the zones which emit successively.
  • the transducer according to the invention and with a matrix structure comprises several parallel and elongated copies of said third electrode, these copies being respectively placed opposite the copies of the second electrode, the transducer further comprises control means provided for successively biasing the first electrodes negatively with respect to the second electrodes, the latter being maintained at the same potential, the third electrodes being maintained at another same potential greater than or equal to the same potential and the detection means are provided for detecting the currents of the third electrodes in response to successive polarizations of the first electrodes.
  • the detection means are further provided for forming, from currents corresponding respectively to the zones a digitized image of the object.
  • object must be taken in a very general sense: it can be a material object such as a sheet of paper with a text or a drawing (case of the application of the invention for the manufacture of photocopiers or facsimile machines), or a scene (case of the application of the invention to the manufacture of video cameras), or a plasma which emits X-rays as desired detect (case of the application of the invention to the manufacture of X cameras or X-ray detectors) ...
  • the modulation can be only spatial, as is the case in the applications of the invention involving static objects (photocopying, faxing, etc.) or spatial and temporal, in the case of applications of the invention involving non-static objects (taking images by video camera for example).
  • a transducer according to the invention and with a matrix structure, provided with a layer of an electrically insulating material and capable of transmitting at least part of said light, this layer being placed between the first and second electrodes, said layer is divided into zones which are separated from each other and arranged between the first and second electrodes, respectively in correspondence with the crossing zones.
  • the transducer according to the invention and with a matrix structure may be provided with an image-forming optic, this optic being arranged on the side of the transducer, which is intended to be reached by said light.
  • Such a particular embodiment aims in particular at the applications of the invention to taking images, photocopying or faxing.
  • Said light can belong to the field of visible radiation.
  • this transducer can also be provided with a light source intended to supply said light and located at a given distance from the optics, in order to be able to place between the source and the optics a material object whose size is compatible with this distance, this object spatially modulating the light.
  • Such a particular embodiment relates in particular to the applications of the invention to photocopying or faxing.
  • said light can belong to the field of X-rays (for the applications of the invention compatible with such radiation).
  • FIG. 1 there is shown schematically a particular embodiment of the transducer which is the subject of the invention, comprising an electrically insulating substrate 2, for example made of glass, on which is deposited an electrically conductive plane layer 4, covered with a layer electrically insulating plane 6, itself covered with an electrically conductive plane layer 8 called a grid.
  • the layers 6 and 8 are pierced with holes 7, 9 regularly spaced from each other which makes the layer appear 4.
  • a substantially conical microtip 10 electrically conductive, which rises from the layer 4 towards layer 8 and the top of which is flush with the surface of this layer 8.
  • An electrically conductive plate 12 serving as an anode is placed opposite the tops of the microtips, parallel to the layer 8.
  • the surface of layer 8 is smaller than that of layer 6 so that this layer 6 protrudes from the periphery of layer 8.
  • Layer 4 is made of a material whose conductivity increases when it is illuminated by visible light or X-rays, material such as p-type silicon (boron doped silicon for example).
  • the resistivity of the material (unlit) is for example of the order of 0.1 to 1 ohm.cm.
  • the number of microtips is for example of the order of 10,000 / mm2 and the constituent material is for example niobium.
  • Layer 6 is also transparent, for example made of silica.
  • the grid 8 is for example made of molybdenum.
  • the assembly comprising the elements referenced 2, 4, 6, 8, 10 in FIG. 1 and the anode 12 being placed under vacuum (for this purpose said assembly can be placed in a glass envelope, in this case producing the anode 12 in the form of a metal layer deposited on the internal face of this envelope, facing the microdots of the assembly and creating a vacuum in this envelope), layer 4 is carried, by means of an appropriate source and therefore the microtips 10 at a negative potential with respect to layer 8 which can be grounded and the anode 12 is brought to a positive potential with respect to layer 8 by means of an appropriate source 16.
  • the - pole of the source 16 and the + pole of the source 14 can thus both be connected to ground.
  • the current Measured electronics for example by means of a micro-ammeter 18 mounted between the + pole of the source 16 and the anode 12, is of the order of 100 microamps.
  • the anode 12 When the anode 12 is a small distance from the layer 8, for example a distance of the order of 1 mm or less, it is not necessary (although possible) to bring the anode to a strongly positive potential by relative to layer 8 (and the anode could then simply be grounded, although it would be better to avoid that layer 8 and anode 12 are strictly at the same potential - for example ground - because the beams of electrons being slightly divergent at the exit of the holes, one would have a poorer spatial resolution than in polarizing the anode positively compared to the layer 8, such a polarization being thus preferable and making it possible to attract the electrons still slightly to their exit from holes 9). But when the distance is greater, it is preferable to bring the anode to a more strongly positive potential with respect to layer 8 in order to obtain a sufficiently large and focused electronic current.
  • the intensity of the electronic current is also an increasing function of the intensity of the light, for a given wavelength of the latter.
  • a He-Ne laser can be used as the light source (emitting at a wavelength of the order of 500 nanometers), this laser producing a punctual light spot, and it is observed that the electronic current is all the more important as the impact of the laser beam is close to the edge of the grid 8.
  • An ordinary lamp can also be used in place of a laser.
  • the increase in the intensity of the electronic current is also observed by using no longer a visible light source but an X-ray source.
  • the increase in the intensity of the electronic current can be explained by a decrease in the interface resistance between the microtips and the conductive layer 4, when the emissive cathode is lit. When it is a visible light, it is "guided” or diffused by the silica layer 6 to the area 19 of the microtips, area in which it decreases said interface resistance.
  • the maximum frequency of pulsation for which an electronic current is also pulsed depends on the resistances and capacities inherent in the structure and the constituents of the emissive cathode with microtips.
  • the photoelectronic transducer shown in FIG. 1 applies for example to a presence detection, by using a visible light source (not shown) intended to illuminate the portion of the layer 6 projecting from the grid 8, so that the interposition of an object between the light source and the transducer causes a variation in the electronic current detected by means of the micro-ammeter.
  • a visible light source not shown
  • the latter can of course be replaced by any means for detecting the variation in electronic current, which means can also be connected to an alarm device.
  • microtip emissive cathode it is also possible to envisage lighting the microtip emissive cathode through the glass substrate 2, said light thus reaching the face not covered with microtips of layer 4 and causing, as already indicated above, a variation in the interface resistances between the microtips and this layer 4.
  • FIG. 2 schematically shows another particular embodiment of the transducer which is the subject of the invention, in which the emissive cathode 20 has a matrix structure. More specifically, on a glass plate 22 are deposited a plurality of conductive and parallel strips 24. An insulating layer 26, for example made of silica, covers these bands 24. A plurality of other conductive and parallel bands 28 perpendicular to the bands 24 are deposited on the insulating layer 26. In the zones 30 "of intersection" of the bands 24 and 28, the strips 28 and the layer 26 are pierced with holes and the strips 24 are provided with microtips like the microtips 10 of FIG. 1, which rest on the strips 24 and are flush with the surface of the strips 28.
  • the transducer schematically represented in FIG. 2 also comprises a plurality of conductive and parallel strips 32 which are deposited on a glass plate 34.
  • This glass plate 34 is placed opposite the strips 28 and the strips 32 are parallel to these strips 28 and arranged on the plate 34 so as to be respectively opposite these bands 28.
  • an interval of the order of 0.1 millimeter to 1 millimeter is provided between the strips 28 and the strips 32, this interval being obtained by means of suitable glass spacers (not shown), uniformly distributed over the surface of the cathode.
  • These strips 32 constitute anodes for the transducer.
  • microtip emissive cathode 20 and the plate 34 provided with the anodes 32, spaced as indicated above, are fixed relative to each other and mounted in a glass envelope 36 sealed under vacuum, as we see it on the FIG. 3 on which the emissive cathode 20 and the plate 34 of FIG. 2 are seen in section perpendicular to the strips 28 and 32.
  • Watertight passages 38 are provided in the walls of the envelope for the passage of electrical connecting conductors between the strips 24 or microtip lines, the strips 28 or grids and the strips 32 or anodes and various control means described below. .
  • the assembly thus obtained can be used to make a photocopying device.
  • said assembly is provided with an appropriate image-forming optic 40.
  • the plate 34 being disposed facing an internal face of the envelope 36, for example parallelepiped, the optics 40 is disposed opposite the corresponding external face 42.
  • Said assembly is also provided with a visible light source 44, preferably intense, which is arranged opposite the optics 40, a sufficient distance from the latter to allow to have between the optics 40 and the source 44 a drawing or a text to be photocopied carried by an appropriate support such as a sheet of paper (45).
  • a visible light source 44 preferably intense, which is arranged opposite the optics 40, a sufficient distance from the latter to allow to have between the optics 40 and the source 44 a drawing or a text to be photocopied carried by an appropriate support such as a sheet of paper (45).
  • the silica layer is divided into a plurality of zones 46, each zone 46 being separated from the adjacent zones 46 and associated with a given area 30 of microtips (FIG. 2).
  • the zones 46 are of course produced so that the bands 28 are not in contact with the bands 24.
  • each zone 46 of silica corresponding to a line 24 of microtips and to a grid 28 is such that it covers the line 24 in the portion thereof, which corresponds to the zone 30 of microtips, associated with the zone 46, while projecting on either side of the grid 28.
  • the source 44 being intended to operate for a certain time, means 48 are provided for bringing all the grids to the same constant potential during this time. Means 50 are provided to bring, during the operating time of the source 44, successively each line of microtips to a negative potential for example of the order of -100V, with respect to the grids while the other lines of microtips are brought to the same potential as these grids.
  • microtip lines thus successively emit electrons, the quantity of electrons emitted by a given microtip zone depending on the illumination of this zone taking into account that the light emitted by the source is spatially modulated by the text or the drawing carried by the sheet 45.
  • the light reaching the emissive cathode can in fact penetrate into each silica zone 46 and, "guided” by it over a short distance, modify the interface resistance of the corresponding microtip zone.
  • the device shown in FIG. 3 also includes means 52 provided for bringing, during the operating time of the source 44, all the anodes to the same positive potential, for example of the order of + 100V, by compared to the grids and to detect and digitize, in synchronism with the polarization of the microtip lines, the electronic currents respectively collected by the anodes (currents being thus detected each time a microtip line is brought to said negative potential with respect to the grids ).
  • the means 52 are connected to means 54 provided for memorizing the digitized currents corresponding respectively to the microtip zones, each microtip zone being identified by the number of the microtip line which corresponds to it (the means 50 being provided to provide this information) and by the number of the anode which corresponds to it (the means 52 being provided to supply this information).
  • the means 54 are connected to means 56 provided for reform the design or text onto the desired amount of suitable media (for example, sheets of paper).
  • suitable media for example, sheets of paper
  • the imaging optics 40 and the source 44 are no longer positioned facing the face 42 of the envelope 36 but facing the external face 58 of the envelope 36, this face 58 corresponding to the internal face of this envelope 36, internal face opposite which is the cathode 20, so that the spatially modulated light can successively pass through the envelope and the glass substrate 2 to reach layer 4 and modify the microtip interface resistance.
  • This variant embodiment is advantageous in the case where the anode network is not sufficiently transparent to light, while noting however that a lack of transparency is compensated for by the intensity of the source 44.
  • the device shown in FIG. 3 can be transformed into a facsimile device, by replacing the means 56 by means for processing the information digitized in the means 54 with a view to their transmission over a telephone line.
  • FIG. 4 a video camera is also shown diagrammatically using the casing 36 provided with the emissive cathode 20 and the plate 34 carrying the anodes 32, which have been described with reference to FIGS. 2 and 3.
  • the video camera comprises an appropriate optic 60 which is arranged opposite the external face 42 of the envelope 36 and which makes it possible to observe a scene 62 lit in visible natural or artificial light.
  • Means such as means 48, 50, 52 and 54 are also used. However, the means 54 are no longer connected to the means 56 described with reference to FIG. 3 but to means 64 provided for viewing the digitized image of the scene, stored in the means 54, or to copy the digitized information onto a recording medium, a video-disc for example.
  • the means 48, 50, 52 and 54 are suitable when taking pictures. Several successive polarizations of the microtip lines are carried out several times per second, at a frequency adapted to the "mobility" of the filmed scene, and the detections and digitizations (associated with these successive polarizations) of the currents collected by the anodes, and the means 54 are provided for successively storing the images filmed at this frequency with the camera, these images then being viewed or copied by means 64.
  • microtips in the embodiments of the invention which have been described with reference to Figures 3 and 4 and which will be described later, with reference to Figure 5, must be large enough for the 'emission of a group of microtips, corresponding to a pixel, is fairly stable over time, in the absence of incident light.
  • the transducer which is the subject of the invention also makes it possible to produce an X camera or an X detector (for example a X location detector), in order to study X rays which can be very intense and sometimes very brief, as produced by plasmas. .
  • FIG. 5 another diagrammatic embodiment of the emissive cathode microtip - anode assembly is shown diagrammatically according to the invention.
  • the emissive cathode shown in FIG. 5 conforms to that shown in FIG. 2.
  • the anode shown in Figure 5 differs from that shown in Figure 2 in that it is no longer made in the form of several parallel strips but in one piece.
  • the anode shown in FIG. 5 is for example constituted by an electrically conductive thin layer 66 sufficiently transparent to the light used (visible or X-rays) and deposited on a glass plate 68.
  • Such an anode can be used in combination with an image-forming optic arranged opposite the plate 68 and of the type of optics 40 or optics 60 (depending on the application chosen).
  • the material of layer 66 can be In2O3.
  • the anode is made of an electrically conductive and opaque layer, for example of aluminum, deposited on the plate 68.
  • the optics are arranged opposite the external face 58 of the envelope 36.
  • the optics are not used and the device is exposed to the scene studied so that the X-rays pass through the external face 42 of the envelope 36 if the anode layer allows it or the external face 58 when the anode layer is opaque to X-rays.
  • the envelope 36 is eliminated, the transducer being placed opposite the X-ray source, the source-transducer assembly being placed under vacuum.
  • FIG. 5 The operation of the particular embodiment shown in FIG. 5 is as follows: a matrix addressing of microtip lines and grids forming columns perpendicular to the lines, so that the microtip zones are successively excited one after the other, electronic currents being then emitted successively by the different microtip zones and detected one after the other the others by the anode 66 (all this of course taking place, in the case of the application to photocopying or faxing, during the operation of the source 44).
  • the microtip lines are controlled by means 70 provided for successively bringing each of the microtip lines to a negative potential, for example of the order of -100 volts, while all the other microtip lines are grounded;
  • the grid columns are controlled by means 72 provided for successively bringing each of the grid columns to earth while the other grid columns are brought to a potential of the order of -100 volts for example, this for a state of given polarization of the microtip lines, the polarization scanning of the grid columns carried out by the means 72 resuming for the polarization state along microtip lines and so on.
  • microtip zones are excited one after the other, the electronic currents obtained depending on the state of illumination of these zones.
  • the anode 66 is connected to means 74 provided for detecting and digitizing the electronic currents successively collected by this anode in response to successive excitations of the microtip zones, and the means 74 are connected to means 76 provided for storing the currents thus digitized , a digitized image therefore being stored in the means 76.
  • Each pixel stored in the means 76 is identified as a function of its row and column coordinates provided by the means 70 and 72 provided for this purpose.
  • the means 76 are themselves connected to image reproduction means 78, in the case of a application of the invention to photocopying, or processing and transmission over a telephone line, in the case of application of the invention to fax.
  • the means 78 are replaced by means display or recording (as already mentioned above in the description of Figure 4) and the means 70, 72, 74 and 76 are adapted, so as to perform, several times per second, the addressing matrix of rows and columns and the detection-digitization-storage of electronic currents, at a frequency suited to the envisaged application.
  • a method for obtaining an emissive cathode with a matrix structure usable in the invention includes the following successive steps: - deposition, by sputtering on an insulating substrate (glass plate), of a first layer of p-doped silicon, - etching of the first layer (through a mask of positive resin and by chemical attack with orthophosphoric acid brought to 110 ° C., the mask then being eliminated by chemical dissolution), to form first parallel bands, - deposition of a second insulating layer of SiO2 on the structure obtained (by a chemical vapor deposition technique from silane, phosphine and oxygen), through an appropriate mask, so that the second layer is divided into strips separated which respectively cover the first bands, each band of the second layer being further divided into zones separated from each other (corresponding to zones 46 Figures 2 and 5), - deposit of a third conductive niobium layer on the second layer (by vacuum evaporation), - hole openings opening into the third and second layers, these holes
  • said first layer can be made of a photoconductive material.
  • the anode in one piece can be formed by vacuum evaporation of a metallic layer of In2O3 on a glass plate. To produce the network of anodes 32, it suffices to carry out this evaporation through an appropriate mask.
  • the desired space between the grids and the anode or the network of anodes 32 is obtained by means of glass spacers randomly distributed over the emissive cathode. .
  • the periphery of the latter is hermetically welded to the anode plate (34 or 68) by means of a fusible glass (crossed by the various electrical conductors necessary for the operation of the transducer) and the assembly obtained is placed under vacuum.
  • the strips 24 have a width of 50 micrometers, a thickness of 1 micrometer and are spaced from each other by 50 micrometers
  • the strips 28 have a width of 50 microns, a thickness of 0.25 microns and are spaced from each other by 50 microns
  • each zone 46 has a thickness of 1.5 micrometers and exceeds 23 micrometers on either side of the corresponding strip 28
  • the layer 66 has a thickness of 0.1 micrometer
  • the strips 32 have a width of 10 micrometers, a thickness of 0.1 micrometers and are spaced from each other by 90 micrometers
  • the holes 9 have a diameter of 1 micrometer
  • - the microtips follow the shape of a cone whose base has a diameter

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Measurement Of Radiation (AREA)
EP87402918A 1986-12-22 1987-12-18 Photoelektronischer Umwandler mit einer aus mehreren Mikrospitzen bestehenden Emissionskathode Ceased EP0275769A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8617973 1986-12-22
FR8617973A FR2608842B1 (fr) 1986-12-22 1986-12-22 Transducteur photo-electronique utilisant une cathode emissive a micropointes

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Publication Number Publication Date
EP0275769A1 true EP0275769A1 (de) 1988-07-27

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EP87402918A Ceased EP0275769A1 (de) 1986-12-22 1987-12-18 Photoelektronischer Umwandler mit einer aus mehreren Mikrospitzen bestehenden Emissionskathode

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FR (1) FR2608842B1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1444718A2 (de) * 2001-11-13 2004-08-11 Nanosciences Corporation Photokathode
FR2879342A1 (fr) * 2004-12-15 2006-06-16 Thales Sa Cathode a emission de champ, a commande optique

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5449970A (en) * 1992-03-16 1995-09-12 Microelectronics And Computer Technology Corporation Diode structure flat panel display
US5548185A (en) * 1992-03-16 1996-08-20 Microelectronics And Computer Technology Corporation Triode structure flat panel display employing flat field emission cathode
US5567929A (en) * 1995-02-21 1996-10-22 University Of Connecticut Flat panel detector and image sensor
CN1119829C (zh) * 1996-09-17 2003-08-27 浜松光子学株式会社 光电阴极及装备有它的电子管
JPWO2008136188A1 (ja) 2007-04-26 2010-07-29 パナソニック株式会社 Ｘ線撮像デバイス及びｘ線撮影装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3735186A (en) * 1971-03-10 1973-05-22 Philips Corp Field emission cathode
US3921022A (en) * 1974-09-03 1975-11-18 Rca Corp Field emitting device and method of making same
EP0127735A1 (de) * 1983-05-03 1984-12-12 DORNIER SYSTEM GmbH Photokathode und Verfahren zu deren Herstellung

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3735186A (en) * 1971-03-10 1973-05-22 Philips Corp Field emission cathode
US3921022A (en) * 1974-09-03 1975-11-18 Rca Corp Field emitting device and method of making same
EP0127735A1 (de) * 1983-05-03 1984-12-12 DORNIER SYSTEM GmbH Photokathode und Verfahren zu deren Herstellung

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1444718A2 (de) * 2001-11-13 2004-08-11 Nanosciences Corporation Photokathode
EP1444718A4 (de) * 2001-11-13 2005-11-23 Nanosciences Corp Photokathode
FR2879342A1 (fr) * 2004-12-15 2006-06-16 Thales Sa Cathode a emission de champ, a commande optique

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Publication number Publication date
FR2608842A1 (fr) 1988-06-24
FR2608842B1 (fr) 1989-03-03

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