US2128580A - Means and method of operating electron multipliers - Google Patents

Means and method of operating electron multipliers Download PDF

Info

Publication number: US2128580A
Authority: US; United States
Prior art keywords: anode; cathode; electron; electrons; frequency
Prior art date: 1936-08-18
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

US96614A

Other languages

English (en)

Inventor

Philo T Farnsworth

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.)

Farnsworth Television Inc

Original Assignee

Farnsworth Television Inc

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.)

1936-08-18

Filing date

1936-08-18

Publication date

1938-08-30

1936-08-18 Application filed by Farnsworth Television Inc filed Critical Farnsworth Television Inc

1936-08-18 Priority to US96614A priority Critical patent/US2128580A/en

1937-08-05 Priority to GB21640/37A priority patent/GB503671A/en

1937-08-18 Priority to FR825746D priority patent/FR825746A/fr

1938-08-30 Application granted granted Critical

1938-08-30 Publication of US2128580A publication Critical patent/US2128580A/en

1955-08-30 Anticipated expiration legal-status Critical

Status Expired - Lifetime legal-status Critical Current

Links

238000000034 method Methods 0.000 title description 28
150000002500 ions Chemical class 0.000 description 6
238000010586 diagram Methods 0.000 description 4
230000001133 acceleration Effects 0.000 description 2
230000001276 controlling effect Effects 0.000 description 2
229910000600 Ba alloy Inorganic materials 0.000 description 1
PXSIFGRGUVISHI-UHFFFAOYSA-N [Ni].[Ba] Chemical compound [Ni].[Ba] PXSIFGRGUVISHI-UHFFFAOYSA-N 0.000 description 1
229910052783 alkali metal Inorganic materials 0.000 description 1
230000003321 amplification Effects 0.000 description 1
230000005540 biological transmission Effects 0.000 description 1
238000006243 chemical reaction Methods 0.000 description 1
230000003116 impacting effect Effects 0.000 description 1
235000015250 liver sausages Nutrition 0.000 description 1
229910052751 metal Inorganic materials 0.000 description 1
239000002184 metal Substances 0.000 description 1
229910021645 metal ion Inorganic materials 0.000 description 1
238000003199 nucleic acid amplification method Methods 0.000 description 1
230000002093 peripheral effect Effects 0.000 description 1
230000001105 regulatory effect Effects 0.000 description 1
230000000630 rising effect Effects 0.000 description 1
XYSQXZCMOLNHOI-UHFFFAOYSA-N s-[2-[[4-(acetylsulfamoyl)phenyl]carbamoyl]phenyl] 5-pyridin-1-ium-1-ylpentanethioate;bromide Chemical compound [Br-].C1=CC(S(=O)(=O)NC(=O)C)=CC=C1NC(=O)C1=CC=CC=C1SC(=O)CCCC[N+]1=CC=CC=C1 XYSQXZCMOLNHOI-UHFFFAOYSA-N 0.000 description 1
230000035945 sensitivity Effects 0.000 description 1

Images

Classifications

- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
- H01J25/76—Dynamic electron-multiplier tubes, e.g. Farnsworth multiplier tube, multipactor

Definitions

My invention relates-to a means and method of operating an electron multiplier, and particularly that form of electron multiplier having as fundamental structure a secondarily emissive cathode surface and an accelerating anode spaced from and paralleling the anode surface.
my invention has to do with the form of electron multiplier I term a multipactor, in that amplification is obtained by repeated and cyclical electron impacts with a. cathode surface adapted to emit secondary electrons at a ratio greater than unity, Ordinarily impacts take place only once per cycle ofthe impressed or primary frequency. k
the present invention relates to a method of there aremultiple electron impacts during each -cycle of operation'of the-device, thus giving rise to what I shall term an electron frequency. As a consequence, this electron frequency being greaterthan the primary frequency, harmonics having large power may be obtained.
FIG. 1 is a sectional view of amultipactor structure which may be used to practice my method, together with a schematic circuit indicating the proper operative connections.
Figure 2 is a diagram of a. diode multipactor operating where the transit time is the'same as" the primary frequency.
Figure 3 is a graph showing the position of the electron with respect to time in a multipactor operated in the circuit of Figure 2.
Figure 4 is a diagram showing a diode multipactor together with an auxiliary electrode for short relative to the primary period.
Figure 5 is a graph showing the position of the electron with respect to time as shown by the operating characteristics of the oscillator shown in Figure 4.
Figure 6 is a graph showing the relative characteristic curves of a multipactor connected as shown in Figure 4.
7 7 I Figurefl is the over-all power-voltage characteristic of the. multipactor oscillator.
this auxiliary I electrode may be positioned and energized in other locations and to other potentials than are H herein to be described, whereas in the present application this ion collector must have a certain position with respect'to the other electrodesfin f order to perform the method I am herein disclosing.
Figure 1 is substantially the same structure as referred to in my prior application mentioned above.
An envelope i is provided at oneend with a re-entrant stem 2 through which pass auxiliary electrode supports 3, supporting a central and preferably axial cylindrical grid structure d.
This stem also supports by means of a peripheral ban 5 a cathode 6 in the form of an unperforated cylinder having its inner surface sensitized to produce secondary emission at ratios greater than unity when being impacted by electrons traveling at a velocity of 20 volts or greater, although, for the purposes of my method such sensitivity is not required but is desirable.
I may, however, make this cathode of'a nickel barium alloy such as has-been described in my patent application Serial No. 70,714, flied March 24,1936.
the opposite end of the tube also has a reentrant stem I sealed thereto supporting a gridlike anode structure 8, which may be formed as shown of the spiral wire welded to supports, or may be a perforated sheet metal assembly, the main point being that it should. be perforated to allow electrons to pass toward the axis of the assembly.
Anode 8 is energized to a high potential. preferably several thousand volts, by
the auxiliary electrode is energized through an auxiliary source I0, preferably vari- ,able, this source energizing the auxiliary electrode to a negative potential, the positive end being grounded.
the cathode 8 has a lead ii passing through the wall of the envelope, this lead going to a tuned circuit ii, the, other end being grounded, thus placing a tuned circuit directly across anode and cathode andproviding the main or primary frequency.
An output circuit i4 is coupled to the tuned circuit l2, and this output circuit'may lead to transmission line or other device as will be explained later. The device is now ready for operation as a selfoscillator if desired, or may be driven if desired, and in this latter instance coil I4 is used to supply the primary frequency between the cathode and anode.
FIG. 2 represents a fundamental electron multiplier structure using a single anode and a single cathode, 'wherein the time of flight of the electron determines the output frequency.
the tuned circuit i2 is designed to have a period equal to a time of flight which is substantially diametrical, and in addition; anode source 91s adjusted so that the acceleration given to the electron will bring the electron across the cathode space in the period selected.
the potential of anode source 9 and the period of tuned circuit l2 should be adjusted so that the. time of flight corresponds to the period.
the anode 8 is made considerably smaller than the cathode 6, thus giving an acceleration toward the axis of the device.
the position of the electron with respect to time will be that. as shown in Figure 3, the electrons leaving the cathode at one point, passing near the 'axis of the cathode cylinder 6 and impacting the amaeso opposite side of the cathode to produce secondaries, these secondaries then returning past the axis to again impact the cathode on an opposite suriace, as indicated by dash lines it in Figure 2.
This action takes place along all diameters and the output current will have its greatest power in the primary frequency as determined by the adjustments and by tuned circuit I2, and there will not be a large harmonic content.
Figure 4 will be found to be a diagram representing schematically a sectional view of Figure l and in this case I have shown the electron path i5 as being a radial path rather than a diametrical path. This is due to the fact that the anode 8 is placed relatively close to the emitting surface of cathode 6 and is therefore much larger in diameter, and that there is a negative potential on the inner auxiliary electrode 4.
Figure 5 is a graph showing the position of the electron with respect to time in my new method of the operation of the device, showing I that there are multiple impacts with the cathode and that these impacts will be greater innumber than the primary frequency.
an electron multiplier having an envelope containing a cathode adapted to emit secondary .electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode adjacent said cathode.
the method of operation which comprises impressing a primary alternating potential between anode and cathode of sufficient intensity to cause electrons from said cathode to pass through said anode, and returning said electrons through said anode a plurality of times during a single period of the primary frequency.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode adjacent said cathode
the-method of op-, eration which comprises impressing a primary alternating potential between anode and cathode of sufilcient intensity to cause electrons from said cathode to pass through said anode, and returning said electrons through'said anode to ⁇ contact said cathode a plurality of times during a single period of .the primary frequency.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode adjacent said cathode
the method of operation which comprises impressing a primary alternating potential between anode and cathode of sufflcient intensity to cause electrons from said which comprises impressing a primary alternating potential between anode and cathode of suflicient intensity to cause electrons from said cathode to pass through said anode, and cyclically re-.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode adjacent said cathode, the method of operation which comprises impressing a primary alternating potential between anode and cathode of sumcient intensity to cause electrons from said cathode to pass through said anode, cyclically returning said electrons through said anode at a secondary frequency greater than the primary frequency, and collecting a portion of the electrons on the anode during each passage therethrough.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode quency, collecting a portion of the electrons on the anode during each passage therethrough, and utilizing the collected current at said secondary frequency.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith, and a perforated anode adjacent said cathode
the method of operation which comprises impressing a primary alternating potential between anode and cathode of suflicient intensity to cause electrons from said cathode to pass through said anode, subjecting said electrons to a negative charge directed to return said electrons through the anode a plurality of times during a single period of the primary period, collecting a portion of the electrons on the anode at each passage therethrough to create a secondary fre-, quency, and utilizing said secondary frequency.
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at a ratio greater than unity upon electron impact therewith; and a perforated anode adjacent said cathode, the method of operation which comprises impressing a primary alternating potential between anode and cathode of sum-- cient intensity to cause electrons from said oath ode to pass through said anode, subjectingsaid electrons to a negative charge directed to return said electrons through the anode a plurality of times during a single period of the primary period,
an electron multiplier having an envelope containing a cathode adapted to emit secondary electrons at .a ratio. greater than unity upon elec-' tron impact therewith, and a perforated anode adjacent said cathode, the method of operation which comprises impressing a primary altemating potential between anode and cathode of sufficient intensity to cause electrons from said cathof generating secondary electrons at a ratio greater than unity which comprises moving electrons away from and'against said surface capable of emitting secondary electrons at a ratio greater than unity and at a predetermined frequency to create successive secondary producing impacts, changing the impact velocity of each successive impact in accordance with a second predeter- 20 mined frequency to create multiple impacts per v tioned frequency.
the method of electron multiplication utilizing electron impact with a surface capable of generating secondary electrons at a ratio greater than unity comprises moving electrons away from and against said surface'capable of emitting secondary electrons at a ratio greater than unity and at a predetermined frequency to create successive secondary producing impacts.

Landscapes

X-Ray Techniques (AREA)
Microwave Tubes (AREA)

US96614A 1936-08-18 1936-08-18 Means and method of operating electron multipliers Expired - Lifetime US2128580A (en)

Priority Applications (3)

Application Number	Priority Date	Filing Date	Title
US96614A US2128580A (en)	1936-08-18	1936-08-18	Means and method of operating electron multipliers
GB21640/37A GB503671A (en)	1936-08-18	1937-08-05	Improvements in means and method of operating electron multipliers
FR825746D FR825746A (fr)	1936-08-18	1937-08-18	Multiplicateur dynamique d'électrons

Applications Claiming Priority (1)

Application Number	Priority Date	Filing Date	Title
US96614A US2128580A (en)	1936-08-18	1936-08-18	Means and method of operating electron multipliers

Publications (1)

Publication Number	Publication Date
US2128580A true US2128580A (en)	1938-08-30

Family

ID=22258220

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
US96614A Expired - Lifetime US2128580A (en)	1936-08-18	1936-08-18	Means and method of operating electron multipliers

Country Status (3)

Country	Link
US (1)	US2128580A (fr)
FR (1)	FR825746A (fr)
GB (1)	GB503671A (fr)

1936
- 1936-08-18 US US96614A patent/US2128580A/en not_active Expired - Lifetime
1937
- 1937-08-05 GB GB21640/37A patent/GB503671A/en not_active Expired
- 1937-08-18 FR FR825746D patent/FR825746A/fr not_active Expired

Also Published As

Publication number	Publication date
GB503671A (en)	1939-04-05
FR825746A (fr)	1938-03-11

Publication	Publication Date	Title
USRE22990E (en)	1948-03-23	Modulation system
US2276806A (en)	1942-03-17	High frequency apparatus
US2141322A (en)	1938-12-27	Cascaded secondary electron emitter amplifier
US2086904A (en)	1937-07-13	Frequency multiplier
US2242888A (en)	1941-05-20	Ultra short wave oscillation generator
US2026892A (en)	1936-01-07	High frequency generator
US2398162A (en)	1946-04-09	Means and method for electron acceleration
US2217187A (en)	1940-10-08	Electrical discharge apparatus
US2128580A (en)	1938-08-30	Means and method of operating electron multipliers
US2073599A (en)	1937-03-09	Electric discharge device
US2071516A (en)	1937-02-23	Oscillation generator
US2217860A (en)	1940-10-15	Split cathode multiplier
US2645739A (en)	1953-07-14	Electron discharge apparatus
US2228895A (en)	1941-01-14	Electrical translating device
US2204479A (en)	1940-06-11	Means and method for producing electron multiplication
US2140832A (en)	1938-12-20	Means and method of controlling electron multipliers
US2121067A (en)	1938-06-21	Double cathode electron discharge device and circuits
US2298673A (en)	1942-10-13	Double cathode electron discharge device and circuits
US2260613A (en)	1941-10-28	Electron multiplier
US2091439A (en)	1937-08-31	Multipactor oscillator and amplifier
US2141838A (en)	1938-12-27	Split cathode multiplier tube
US2181170A (en)	1939-11-28	Electronic device
US2307693A (en)	1943-01-05	Frequency multiplier
US2420846A (en)	1947-05-20	Cathode-ray tube for generating oscillations
US2190731A (en)	1940-02-20	Frequency changer