US3758803A - Electric discharge devices - Google Patents

Electric discharge devices Download PDF

Info

Publication number
US3758803A
US3758803A US00227392A US3758803DA US3758803A US 3758803 A US3758803 A US 3758803A US 00227392 A US00227392 A US 00227392A US 3758803D A US3758803D A US 3758803DA US 3758803 A US3758803 A US 3758803A
Authority
US
United States
Prior art keywords
cathode
anode
film
particles
electric discharge
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 - Lifetime
Application number
US00227392A
Inventor
K Cook
R Wheldon
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.)
MO Valve Co Ltd
Original Assignee
MO Valve Co Ltd
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 MO Valve Co Ltd filed Critical MO Valve Co Ltd
Application granted granted Critical
Publication of US3758803A publication Critical patent/US3758803A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03H—PRODUCING A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03H1/00—Using plasma to produce a reactive propulsive thrust
    • F03H1/0037—Electrostatic ion thrusters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/38—Cold-cathode tubes
    • H01J17/40—Cold-cathode tubes with one cathode and one anode, e.g. glow tubes, tuning-indicator glow tubes, voltage-stabiliser tubes, voltage-indicator tubes
    • H01J17/44—Cold-cathode tubes with one cathode and one anode, e.g. glow tubes, tuning-indicator glow tubes, voltage-stabiliser tubes, voltage-indicator tubes having one or more control electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/02—Electrodes; Magnetic control means; Screens
    • H01J23/04—Cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J27/00—Ion beam tubes
    • H01J27/02—Ion sources; Ion guns
    • H01J27/08—Ion sources; Ion guns using arc discharge
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0064—Tubes with cold main electrodes (including cold cathodes)
    • H01J2893/0065—Electrode systems
    • H01J2893/0068—Electrode systems electrode assembly with control electrodes, e.g. including a screen

Definitions

  • ABSTRACT An electric discharge device has a cold cathode of 521 U.S. Cl 313/174, 315/35, 315/330, Solid easily vapofilable material, and a triggering 313/178, 313/181, 313/198, 313/201 rangement comprising a dielectric member, disposed 51 Int. Cl. H0lk 1/50 the cathode and anode and having one Side a [58] Field of Search 3 1 3/174, 178, 179, sputtered film of easily vaporilable material and on the 313/181, 198, 201; 315/35, 330, 335 other side a trigger electrode.
  • the device operates at high vacuum, and a discharge can be triggered by ap- 56] References Cited plying a voltage pulse to the trigger electrode, causing UNITED STATES PATENTS vaporization of material from the film.
  • the device may be a switching device, a travelling-wave 3,087,092 4/1963 Lafferty 313/178 X device or an ion propulsion device 3,255,376 6/1966 Elchenbaum...
  • an easily vaporizable material is meant a material having a latent heat of vaporization less than 50 kilocalories per mole, and a vapor pressure at l000 C greater than 0.l torr.
  • a vacuum is meant a pressure of less than ltorr.
  • - Said particles may, for example, have diameters in the range 2-10 microns, and be spaced apart by-similar distances from each other.
  • a device in accordance with the invention will comprise an evacuable envelope completely enclosing the anode and cathode so as to allow said vacuum to be produced.
  • Said member of dielectric material may then comprise part of the envelope.
  • the device is intended to operate in an evacuated environment, e.g., in the case where the device is an ion propulsion device for use in the vacuum of outer space, no such envelope is required.
  • said film is formed by sputtering of material from the cathode in an arc discharge.
  • Another object of the invention is to provide a novel form of electric discharge device for producing an electron or ion beam.
  • an electric discharge device comprises an anode, a cold cathode of a solid, easily vaporizable material, the arrangement being such that when the anode and cathode are maintained in a vacuum and when a suitable voltage is applied between the anode and cathode a discharge can be initiated between the anode and cathode, sustained by a plasma formed from material vaporized from the cathode, and means for extracting ions or electrons from said plasma to form a beam of ions or electrons as the case may be.
  • Said means for extracting ions or electrons conveniently comprises an accelerating electrode adapted to pulsion device, for use in the vacuum of outer space, no such envelope is required.
  • Said easily vaporizable material may comprise, for example, cadmium, zinc, bismuth or magnesium.
  • FIG. 1 is a schematic sectional elevation of a switching device
  • FIG. 2 is a schematic sectional elevation of a part of a microwave device.
  • FIG. 3 is a schematic sectional elevation of an ion propulsion device.
  • the switching device comprises a cup-shaped glass envelope 1.
  • a cathode 2 is disposed within the envelope 1, and comprises a solid mass of cadmium at the base of theenvelope.
  • a cup-shaped metal anode 3 is disposed within the envelope, and spaced approximately 2mm from the cathode 2.
  • Anode and cathode leads, 4 and 5, sealed through the wall of the envelope 1, are provided for making external electrical connection to the anode and cathode.
  • the envelope 1 is evacuated to a pressure of less than 10 torr. 7
  • a thin film 6 of cadmium is formed on the inner surface of the envelope 1 by sputtering cadmium from the cathode 2 in an arc discharge.
  • the film 6 is not continuous, microscopic examination showing it to consist of a large number of discrete particles, some relatively large, and others relatively small. Typically, said particles have diameters in the range 2-10 microns and are spaced apart by similar distances.
  • the film 6 is in electrical contact with the cathode 2, and extends up the inner surface of the envelope to a region where it lies adjacent the outer surface of the anode 3. The gap between the film and the anode in this region is approximately lmm.
  • An external trigger electrode 7 is formed on the outside surface of the envelope 1, in the form of a band completely encircling the envelope, in the region of the lmrn spacing between the film and the anode.
  • a discharge can be initiated between the anode and cathode by applying a trigger pulse, typically of magnitude 2 kilovolts and with a rate of rise of the order of l kilovolt/microsecond, between the trigger electrode 7 and the cathode 2.
  • a trigger pulse typically of magnitude 2 kilovolts and with a rate of rise of the order of l kilovolt/microsecond.
  • the capacitance between the trigger electrode 7 and the cathode 2 is of the order of 10 picofarads, so that when the trigger pulse is applied capacitative current of the order of 10 milliamps flows between the trigger electrode and cathode, via the sputtered film 6.
  • the device is effectively a vacuum valve before triggering, but after triggering, due to vaporization of cadmium from the cathode 2 and the film 6, acts effectively as a gas-filled device.
  • the triggering of the discharge is very rapid, being sufficiently fast to support a current pulse rising in less than I microsecond.
  • the hold-off voltage can be in excess of kilovolts.
  • the device has a potential use as a pulse modulator.
  • the device does not have a gas filling, the problem of so-called gas clean up does not arise.
  • the device requires no heater power, starts virtually instantanesouly, and can operate over a wide range of ambient temperatures. Since the cathode is solid, the device can operate in any position.
  • the microwave device includes an elongated evacuated glass envelope 11, at one end of which is an electron gun, comprising: a solid cadmium cathode 12, a metal anode 13, aninternal sputtered cadmium film 14, of discrete microscopic particles and an external trigger electrode 15, similar to the corresponding parts in the device in FIG. 1.
  • a discharge can be initiat ed between the anode l3 and the cathode 12 by application of -a trigger pulse between the electrode 15 and the cathode 12.
  • a cadmium plasma is formed between the anode and the cathode.
  • Electrons can be extracted from this plasma, via an In this way, there is formed a beam 18 of electrons,
  • This electron beam is passed down the axis of the envelope 11, to an electron collector 19, which is held at the same potential as the electrode 17.
  • travelling wave tube structure comprising a helix 30,'surrounded by a solenoidal magnet 31 which serves to collimate the electron beam 18.
  • a microwave signal introduced into an input waveguide 32 is coupled into one terminal 33 of the helix, and travels down to the other terminal 34 of the helix, where it is coupled into an output waveguide 35.
  • the field produced by the wave travelling down the helix interacts with the electron beam 18 and, provided the phase relations are correctly chosen, the wave absorbs energy from the electron beam, and hence is amplified.
  • Such a device starts virtually instantaneously, and requires no heater power.
  • the travelling wave structure may be replaced by a known slow wave structure.
  • the ion propulsion device comprise a glass envelope 2], a solid cadmium cathode 22, a metal anode 23, having an aperture 24, an internal sputtered cadmium film 25 of discrete microscopic particles, an external trigger electrode 26, and a tubu- 4 lar accelerating electrode 27, similar to the corresponding parts of the device in FIG. 2.
  • the envelope 21 has an opening 28 in its end remote from the cathode.
  • the ion propulsion device is intended to operate in the vacuum of outer space, so that in operation, the inside of the envelope is at a suitably low pressure.
  • a discharge can be initiated between the anode 23 and the cathode 22 by application of a trigger pulse between the electrode 26 and the cathode 22, so as to form a cadmium plasma.
  • Positively charged cadmium ions are extracted from the plasma, and accelerated to form an ion beam 29 of high energy, typically of the order of SkeV, by means of the accelerating electrode 27, to which is applied a negative potential with respect to the anode 23, the ions being ejected from the device through the opening 28.
  • a thrust is produced, in the opposite direction to that in which the ions are accelerated, which thrust can be used to propel or maneuver a space vehicle.
  • An electric discharge device comprising:
  • said particles being spaced apart from each other and being of different sizes
  • a trigger electrode said trigger electrode being capacitively coupled to said film via said dielectric member
  • said film being positioned to allow material vaporized from the particles thereof to form a plasma in the region of said anode and cathode.
  • An electric discharge device according to claim 1 wherein said film is formed by sputtering of material from said cathode in an arc discharge.
  • An electric discharge device further including an evacuable envelope completely enclosing the anode and cathode for maintaining a vacuum in the region of the anode and cathode.
  • said member of dielectric material comprises part of said envelope, said film of discrete particles being formed on an inner surface of said envelope adjacent said anode, and said trigger electrode being 3,758,803 6 formed on an outer surface of said envelope adjacent from the cathode when a discharge is passing between said film.
  • An electric discharge device further including means for extracting charged partiucles' cles from a plasma formed from material vaporized 5 I anode and cathode to form a beam of said charged par-

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electron Sources, Ion Sources (AREA)

Abstract

An electric discharge device has a cold cathode of solid, easily vaporizable material, and a triggering arrangement comprising a dielectric member, disposed near the cathode and anode, and having on one side a sputtered film of easily vaporizable material and on the other side a trigger electrode. The device operates at high vacuum, and a discharge can be triggered by applying a voltage pulse to the trigger electrode, causing vaporization of material from the film. For example, the device may be a switching device, a travelling-wave device, or an ion propulsion device.

Description

United States Patent 1 1111 3,758,803
Cook et a1. 1 1 Sept. 11, 1973 154] ELECTRIC DISCHARGE DEVICES 3,465,192 9/1969 Lafferty 313/173 X 3,331,981 7/1967 L ffert [75} Inventors: Kenneth George Cook, Northwood; 3,394.28] 7/968 3 n t 4 Robert J p Wheldon, Chalfont, 3,243,640 3 1966 Eichenbaum 315/35 St. Peter, both of England 73 Assignee: The M-O Valve Company Limited, Primary ExaminerRudolph Rolinec London, England l t gant Examiner Saxt1eld Chatmon,Jr. Attorney- Morris Kirschstein. Bertram Ottinger et al. [22] Filed: Feb. 18, 1972 [21] Appl. No.: 227,392 [57] ABSTRACT An electric discharge device has a cold cathode of 521 U.S. Cl 313/174, 315/35, 315/330, Solid easily vapofilable material, and a triggering 313/178, 313/181, 313/198, 313/201 rangement comprising a dielectric member, disposed 51 Int. Cl. H0lk 1/50 the cathode and anode and having one Side a [58] Field of Search 3 1 3/174, 178, 179, sputtered film of easily vaporilable material and on the 313/181, 198, 201; 315/35, 330, 335 other side a trigger electrode. The device operates at high vacuum, and a discharge can be triggered by ap- 56] References Cited plying a voltage pulse to the trigger electrode, causing UNITED STATES PATENTS vaporization of material from the film. For example, the device may be a switching device, a travelling-wave 3,087,092 4/1963 Lafferty 313/178 X device or an ion propulsion device 3,255,376 6/1966 Elchenbaum... 3l5/3.5 3,611,008 10/1971 Anderson 313/178 5 Claims, 3 Drawing Figures Generator Pulse and cathode having on one side a film of discrete separated microscopic particles of easily vaporizable material, said particles being of different sizes, and on the other side, electrically insulated from said film, a trigger electrode, whereby, when the anode and cathode are. maintained in a vacuum, and when a suitable voltage is applied between the anode and the cathode, application of a suitable voltage pulse between the trigger electrode and the particles of said film causes vaporization of material from said film so as to cause a discharge to be initiated between the anode and cathode.
By an easily vaporizable material is meant a material having a latent heat of vaporization less than 50 kilocalories per mole, and a vapor pressure at l000 C greater than 0.l torr. By a vacuum is meant a pressure of less than ltorr.
- Said particles may, for example, have diameters in the range 2-10 microns, and be spaced apart by-similar distances from each other.
Generally, a device in accordance with the invention will comprise an evacuable envelope completely enclosing the anode and cathode so as to allow said vacuum to be produced. Said member of dielectric material may then comprise part of the envelope.
However where the device is intended to operate in an evacuated environment, e.g., in the case where the device is an ion propulsion device for use in the vacuum of outer space, no such envelope is required.
Conveniently, said film is formed by sputtering of material from the cathode in an arc discharge.
Another object of the invention is to provide a novel form of electric discharge device for producing an electron or ion beam. Y
Thus, according to another aspect of the invention an electric discharge devicecomprises an anode, a cold cathode of a solid, easily vaporizable material, the arrangement being such that when the anode and cathode are maintained in a vacuum and when a suitable voltage is applied between the anode and cathode a discharge can be initiated between the anode and cathode, sustained by a plasma formed from material vaporized from the cathode, and means for extracting ions or electrons from said plasma to form a beam of ions or electrons as the case may be.
Said means for extracting ions or electrons conveniently comprises an accelerating electrode adapted to pulsion device, for use in the vacuum of outer space, no such envelope is required.
Said easily vaporizable material may comprise, for example, cadmium, zinc, bismuth or magnesium.
Three electric discharge devices in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, of which:
FIG. 1 is a schematic sectional elevation of a switching device;
FIG. 2 is a schematic sectional elevation of a part of a microwave device; and
FIG. 3 is a schematic sectional elevation of an ion propulsion device.
Referring to FIG. 1, the switching device comprises a cup-shaped glass envelope 1. A cathode 2 is disposed within the envelope 1, and comprises a solid mass of cadmium at the base of theenvelope. Also disposed within the envelope is a cup-shaped metal anode 3, supported by means not shown, and spaced approximately 2mm from the cathode 2. Anode and cathode leads, 4 and 5, sealed through the wall of the envelope 1, are provided for making external electrical connection to the anode and cathode.
The envelope 1 is evacuated to a pressure of less than 10 torr. 7
A thin film 6 of cadmium is formed on the inner surface of the envelope 1 by sputtering cadmium from the cathode 2 in an arc discharge. The film 6 is not continuous, microscopic examination showing it to consist of a large number of discrete particles, some relatively large, and others relatively small. Typically, said particles have diameters in the range 2-10 microns and are spaced apart by similar distances. The film 6 is in electrical contact with the cathode 2, and extends up the inner surface of the envelope to a region where it lies adjacent the outer surface of the anode 3. The gap between the film and the anode in this region is approximately lmm.
An external trigger electrode 7 is formed on the outside surface of the envelope 1, in the form of a band completely encircling the envelope, in the region of the lmrn spacing between the film and the anode.
In operation of the device, when a voltage, for example of the order of [00 volts, is applied between the anode and cathode, a discharge can be initiated between the anode and cathode by applying a trigger pulse, typically of magnitude 2 kilovolts and with a rate of rise of the order of l kilovolt/microsecond, between the trigger electrode 7 and the cathode 2. Typically, the capacitance between the trigger electrode 7 and the cathode 2 is of the order of 10 picofarads, so that when the trigger pulse is applied capacitative current of the order of 10 milliamps flows between the trigger electrode and cathode, via the sputtered film 6.
Consideration of the capacitances between the trigger electrode 7 and the sputtered film 6, and between thediscrete particles of the film 6, suggests that when the trigger pulse is applied a voltage stress is set up between the discrete partgicles, in particular between large and small particles. It is throught that this stress initiates field emission with sufficient dissipation of energy in the film to cause vaporization of cadmium from the film. This vaporized material produces a plasma, which initiates the discharge between the anode 3 and cathode 2.
It will be seen that the device is effectively a vacuum valve before triggering, but after triggering, due to vaporization of cadmium from the cathode 2 and the film 6, acts effectively as a gas-filled device.
Because of the very small spacing between the anode 3 and the cathode 2 and film 6, the triggering of the discharge is very rapid, being sufficiently fast to support a current pulse rising in less than I microsecond. However, since the device is effectively a vacuum valve when it is not triggered, the hold-off voltage can be in excess of kilovolts. Thus, the device has a potential use as a pulse modulator.
Since the device does not have a gas filling, the problem of so-called gas clean up does not arise. In addition, the device requires no heater power, starts virtually instantanesouly, and can operate over a wide range of ambient temperatures. Since the cathode is solid, the device can operate in any position.
Referring now to FIG. 2, the microwave device includes an elongated evacuated glass envelope 11, at one end of which is an electron gun, comprising: a solid cadmium cathode 12, a metal anode 13, aninternal sputtered cadmium film 14, of discrete microscopic particles and an external trigger electrode 15, similar to the corresponding parts in the device in FIG. 1. As in the case of FIG. 1', in operation, a discharge can be initiat ed between the anode l3 and the cathode 12 by application of -a trigger pulse between the electrode 15 and the cathode 12. When a discharge is passing, a cadmium plasma is formed between the anode and the cathode.
Electrons can be extracted from this plasma, via an In this way, there is formed a beam 18 of electrons,
typically with energies of the order of 2-20keV. This electron beam is passed down the axis of the envelope 11, to an electron collector 19, which is held at the same potential as the electrode 17.
Between the gun and the collector 19, the electron beam passes through travelling wave tube structure, comprising a helix 30,'surrounded by a solenoidal magnet 31 which serves to collimate the electron beam 18. A microwave signal introduced into an input waveguide 32 is coupled into one terminal 33 of the helix, and travels down to the other terminal 34 of the helix, where it is coupled into an output waveguide 35. The field produced by the wave travelling down the helix interacts with the electron beam 18 and, provided the phase relations are correctly chosen, the wave absorbs energy from the electron beam, and hence is amplified.
Travelling wave tube structures are, of course, known per se, and the'details of their design and operation are therefore not discussed here.
Such a device starts virtually instantaneously, and requires no heater power.
In a modification of the device shown in FIG. 2, the travelling wave structure may be replaced by a known slow wave structure.
Referring now to FIG. 3, the ion propulsion device comprise a glass envelope 2], a solid cadmium cathode 22, a metal anode 23, having an aperture 24, an internal sputtered cadmium film 25 of discrete microscopic particles, an external trigger electrode 26, and a tubu- 4 lar accelerating electrode 27, similar to the corresponding parts of the device in FIG. 2.
In contrast to the case of FIG. 2, however, the envelope 21 has an opening 28 in its end remote from the cathode. The ion propulsion device is intended to operate in the vacuum of outer space, so that in operation, the inside of the envelope is at a suitably low pressure. Thus, as in the case of FIG. 2, in operation, a discharge can be initiated between the anode 23 and the cathode 22 by application of a trigger pulse between the electrode 26 and the cathode 22, so as to form a cadmium plasma.
Positively charged cadmium ions are extracted from the plasma, and accelerated to form an ion beam 29 of high energy, typically of the order of SkeV, by means of the accelerating electrode 27, to which is applied a negative potential with respect to the anode 23, the ions being ejected from the device through the opening 28. In this way, a thrust is produced, in the opposite direction to that in which the ions are accelerated, which thrust can be used to propel or maneuver a space vehicle.
Such a device has the following advantages over known hot cathode mercury ion engines:
a. No separate power is required to vapourise propellant.
b. No hot cathode is required.
0. No magnet is needed.
a d. No close control of pressure is required between inside of device and outside (space vacuum).
What we claim is:
.1. An electric discharge device comprising:
an anode;
a cold cathode of a solid easily vaporizable material spaced from and electrically insulated from said anode;
means for applying a positive voltage to the anode relative to the'cathode;
a dielectric member disposed in the region of the anode and the cathode,
having on one side a film of discrete microscopic particles' of easily vaporizable material,
said particles being spaced apart from each other and being of different sizes, and
having on the other side, electrically insulated from and substantially parallel to said film,
a trigger electrode, said trigger electrode being capacitively coupled to said film via said dielectric member;
means for applying a voltage pulse between the trigger electrode and the particles of said film;
said film being positioned to allow material vaporized from the particles thereof to form a plasma in the region of said anode and cathode.
2. An electric discharge device according to claim 1 wherein said film is formed by sputtering of material from said cathode in an arc discharge.
3. An electric discharge device according to claim 1, further including an evacuable envelope completely enclosing the anode and cathode for maintaining a vacuum in the region of the anode and cathode.
4. An electric discharge device according to claim 1 wherein said member of dielectric material comprises part of said envelope, said film of discrete particles being formed on an inner surface of said envelope adjacent said anode, and said trigger electrode being 3,758,803 6 formed on an outer surface of said envelope adjacent from the cathode when a discharge is passing between said film.
5. An electric discharge device according to claim' 1 further including means for extracting charged partiucles' cles from a plasma formed from material vaporized 5 I anode and cathode to form a beam of said charged par-

Claims (5)

1. An electric discharge device comprising: an anode; a cold cathode of a solid easily vaporizable material spaced from and electrically insulated from said anode; means for applying a positive voltage to the anode relative to the cathode; a dielectric member disposed in the region of the anode and the cathode, having on one side a film of discrete microscopic particles of easily vaporizable material, said particles being spaced apart from each other and being of different sizes, and having on the other side, electrically insulated from and substantially parallel to said film, a trigger electrode, said trigger electrode being capacitively coupled to said film via said dielectric member; means for applying a voltage pulse between the trigger electrode and the particles of said film; said film being positioned to allow material vaporized from the particles thereof to form a plasma in the region of said anode and cathode.
2. An electric discharge device according to claim 1 wherein said film is formed by sputtering of material from said cathode in an arc discharge.
3. An electric discharge device according to claim 1, further including an evacuable envelope completely enclosing the anode and cathode for maintaining a vacuum in the region of the anode and cathode.
4. An electric discharge device according to claim 1 wherein said member of dielectric material comprises part of said envelope, said film of discrete particles being formed on an inner surface of said envelope adjacent said anode, and said trigger electrode being formed on an outer surface of said envelope adjacent said film.
5. An electric discharge device according to claim 1 further including means for extracting charged particles from a plasma formed from material vaporized from the cathode when a discharge is passing between anode and cathode to form a beam of said charged particles.
US00227392A 1972-02-18 1972-02-18 Electric discharge devices Expired - Lifetime US3758803A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US22739272A 1972-02-18 1972-02-18

Publications (1)

Publication Number Publication Date
US3758803A true US3758803A (en) 1973-09-11

Family

ID=22852924

Family Applications (1)

Application Number Title Priority Date Filing Date
US00227392A Expired - Lifetime US3758803A (en) 1972-02-18 1972-02-18 Electric discharge devices

Country Status (1)

Country Link
US (1) US3758803A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4260934A (en) * 1976-05-05 1981-04-07 U.S. Philips Corporation Electric device provided with a switch which is designed as a discharge tube
US4336277A (en) * 1980-09-29 1982-06-22 The Regents Of The University Of California Transparent electrical conducting films by activated reactive evaporation
GB2469677A (en) * 2009-04-22 2010-10-27 Lincoln Augustus George Simpson Plasma engine having a linear particle accelerator

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3087092A (en) * 1961-05-10 1963-04-23 Gen Electric Gas generating switching tube
US3243640A (en) * 1963-02-08 1966-03-29 Rca Corp Space-charge neutralized electron gun
US3255376A (en) * 1962-01-02 1966-06-07 Rca Corp Low-noise electron guns
US3331981A (en) * 1964-12-11 1967-07-18 Gen Electric Triggerable vacuum discharge devices with a gas producing trigger electrode
US3394281A (en) * 1966-09-07 1968-07-23 Gen Electric Triggered vacuum gap device having field emitting trigger assembly
US3465192A (en) * 1966-09-21 1969-09-02 Gen Electric Triggerable arc discharge devices and trigger assemblies therefor
US3611008A (en) * 1970-03-27 1971-10-05 Gen Electric Metal vapor arc microwave switch

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3087092A (en) * 1961-05-10 1963-04-23 Gen Electric Gas generating switching tube
US3255376A (en) * 1962-01-02 1966-06-07 Rca Corp Low-noise electron guns
US3243640A (en) * 1963-02-08 1966-03-29 Rca Corp Space-charge neutralized electron gun
US3331981A (en) * 1964-12-11 1967-07-18 Gen Electric Triggerable vacuum discharge devices with a gas producing trigger electrode
US3394281A (en) * 1966-09-07 1968-07-23 Gen Electric Triggered vacuum gap device having field emitting trigger assembly
US3465192A (en) * 1966-09-21 1969-09-02 Gen Electric Triggerable arc discharge devices and trigger assemblies therefor
US3611008A (en) * 1970-03-27 1971-10-05 Gen Electric Metal vapor arc microwave switch

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4260934A (en) * 1976-05-05 1981-04-07 U.S. Philips Corporation Electric device provided with a switch which is designed as a discharge tube
US4336277A (en) * 1980-09-29 1982-06-22 The Regents Of The University Of California Transparent electrical conducting films by activated reactive evaporation
GB2469677A (en) * 2009-04-22 2010-10-27 Lincoln Augustus George Simpson Plasma engine having a linear particle accelerator

Similar Documents

Publication Publication Date Title
US3831052A (en) Hollow cathode gas discharge device
US2842706A (en) Cold cathode vacuum tube
GB1355365A (en) Electron guns
US4247804A (en) Cold cathode discharge device with grid control
US3999072A (en) Beam-plasma type ion source
US3465205A (en) Vacuum gap devices with metal ionizable species evolving trigger assemblies
US3949260A (en) Continuous ionization injector for low pressure gas discharge device
US3448314A (en) Neutron generators
Hasseltine et al. Cesium‐Ion Bombardment of Aluminum Oxide in a Controlled Oxygen Environment
US3758803A (en) Electric discharge devices
US3663855A (en) Cold cathode vacuum discharge tube with cathode discharge face parallel with anode
US3757518A (en) Ion engine
US3303376A (en) Triggered vacuum gap device employing gas evolving electrodes
US3614440A (en) Gas ionizer devoid of coaxial electrodes
US3344298A (en) Flash x-ray tube with gas focusing of beam
US3552124A (en) Ion thrustor accelerator system
US2316276A (en) Electron discharge apparatus
US4939425A (en) Four-electrode ion source
US3331981A (en) Triggerable vacuum discharge devices with a gas producing trigger electrode
US2122932A (en) Gaseous discharge tube
US3898518A (en) Gas filled thyratron type switching discharge tubes
US5418423A (en) Capacitively coupled trigger for pseudogap cold cathode thyratrons
US3569755A (en) Vacuum tube and method of making it
US2236289A (en) Thermionic device
US2242042A (en) Cold cathode for electric vacuum tubes