US2460402A

US2460402A - Electron discharge device

Info

Publication number: US2460402A
Application number: US614692A
Authority: US
Inventors: George C Sziklai
Original assignee: RCA Corp
Current assignee: RCA Corp
Priority date: 1945-09-06
Filing date: 1945-09-06
Publication date: 1949-02-01
Anticipated expiration: 1966-02-01

Description

Feb. 1, 1949. s; CSZIKLAI ELECTRON DISCHARGE DEVICE Filed Sept 6, 1945 INVENTOR 65am? 6. Sz/KM/ 'ATTORNEY Patented Feb. 1, 1949 I STAT ZAQA ELECTRON DISGHARGE DEVICE George (1. Szilglai, Princeton, N. 3., assignor to Delaware Radio Corporation of America, a corporation of Application September 6, 1945, Serial No. 614,692.

7 Claims. (Cl. 3156) 1 Myinventionrelates to electron discharge deuseful at ultra high frequencies and more ularly to such. devices employing velocity In 192? 9? inductive Output and utilizing r ts: monsters.

The prir "pal'object ofrny invention is to provides; velocity modulated oscillator capable of deliver e. man owe at high. f e s an with improved efficiencies, and to the methods for mod la i sai de i s- Thenovel' features which I believe to be characteristic of my invention are set forth with arti ularity n. tbeapnc cls c aim but the vehtion;it's if will best be understood. by reference to; tb fql ow ne des i ti n take in onn w th th accom an n draw w h Figure I is a sche atic longitudinal section of an electron disohargedevice made according to my inveni cn and F gure 21. a dia ramma n tu dinal section of a modification oi the device sh n 11 F ure 1 I In accordance wtih my. invention the electron disc r de c is pr ide i an on e envelope H3" having: a transverse oiTset portion "l' Mounted a ne ta of en e e is an nd qtl'y' heat a anode. u a be m m n electrode i2; electrons being directed toward a collector It at the other end of the envelope. Positioned intermediate the cathode and collector is an electromagnet ltffor providing a magnetic field transverseto the path of the beam of electrons. As a resultof this field the electrons take the curved path indicated and. are directed toward reflecting electrode M" passing through the resonator l6 and being reflected back along the dotted path. tolthe; magnetic. field which causes the electron path to reverse itself and be directed toward the collector l3. The beam on passing through the grids l6 ofthe resonator t6; issub- ,i'ected to av-elocit-y modulation, becomes-bunched and; passing through the resonator again, maintains'the resonator in oscillation, causing this portion of the device to act in the manner of a reflex oscillator or as a space charge grid Barkhausen oscillator,

i The bunched electrons then pass through the grid H of the resonator l'l inducing a high frequency voltage in this resonator, which in turn velocity modulates the beam again, thus accentu" ating the bunching. The beam then is directed through the grids l8 of the resonator l8, energy being extracted in a manner now well known. The electrons are then collected by the collector l3. A'coupling loop 30 may be used for extracting energy in the usual manner.

Thevoltagesourcesis, 20 and 2!. are provided ior applying the proper voltages to the various electrodes, the resonators- Hi, il and #8 being maintained. at high positive potentials, the reilector. H5, being properly biased to reflect the electrons as described above, the collector i 3 being maintained at a lower positive potential for re". ceiving the electrons.

Since the same beam. current is used in all stages, higher. efficiency may be obtained than in conventional oscillators utilizing cavityv resona: tors. The cascade amplifier portion,..particularly the resonator ll, acts as a. bufier and prevents interaction between the output resonator section it and the oscillator section !6. By use of the magnetic field the. combination or" the oscillator and amplifier sections is made possible with the result that theinput power. may bematerially reduced it is also obvious'that by. changing the potential of the reflector M within limits the oscillator rnay be frequently modulated. Thus the output off the devicemay be. frequently modulated y th sam iece y In order to amplitude modulate the device the beam current passing the last resonator it must be varied. Thisvariation, however, must be' effected after the beam passes through the oscillator, otherwise frequency modulation will occur simultaneously. A device foraccomplisb ing amplitude mqdulationis disclosedinF-igure 2.

In Figure 2 like numerals refer to like parts as in Figure 1', the amplifier section alone being different. The beam after being velocity, modulated by the oscillator portion of the envelope passes through the bufier stage ll and'entersthe deflection field between deflecting plates and Z3, deflecting the beamacross the aperture or gate 2*! in the apertured plate 2E; the amount of deflection determining the beam density and hence the output current. The amount of current pass.- ingthrough the gate or aperture isdetermined by the amplitude of the potential applied to the deflecting plates 22, 23. In order to straighten the beam after passage through the aperture 24, a second set of deflecting electrodes 25 and 26 are provided, these deflecting electrodes being crossconnected with the plates 22 and 23 so that the same potential is applied twice but in opposite directions to straighten out the beam path. The device shown in Figure 2 possesses all of the advantages of the device shown in Figure 1.

While I have indicated the preferred embodiments of my invention of which I am now aware and have also indicated only one specific application for which my invention may be employed,

it will be apparent that my invention is by no means limited to the exact forms illustrated or the use indicated, but that many variations may be made in the particular structure used and the purpose for which it is employed without departing from the scope of my invention as set forth in the appended claims.

What I claim as new is:

1. An electron discharge device having cathode means for directing a stream of electrons along a beam path, an electrode in said path toward which said electrons are directed, means for deflecting said stream at an angle to said path, means for velocity modulating said deflected elec trons and returning said electrons along said first path toward said electrode, means for further velocity modulating said returned electrons, and means for extracting energy from said velocity modulated electron stream.

2. An electron discharge device having a cathode for directing electrons along a predetermined path, means for generating a magnetic field transversely to said path for causing said electrons to be deflected from said path, means for velocity modulating said deflected electrons and for directing said electrons back toward said path including a first resonator and a reflecting electrode, a second resonator in the path of said electrons for further velocity modulating said electrons, a third resonator for extracting energy irom said electrons, and a collector for said electrons,

3. An electron discharge device having a cathode for directing electrons along a predetermined path, an electrode toward which said electrons are directed, means for generating a magnetic field transversely to said path ,for causing said electrons to be deflected from said path, means for velocity modulating said deflected electrons and for directing said electrons back toward said path including a first resonator and a reflecting electrode, a second resonator in the path of said electrons for further velocity modulating said electrons, and a third resonator following said second resonator for extracting energy from said electrons.

4. An, electron discharge device having an elongated envelope and an offset portion transverseto said elongated portion, a cathode at one endof said electrode and a first electrode at the other end of said envelope, said cathode directing electrons toward said electrode, means positioned adjacent said envelope for directing a magnetic field transversely to said electron path at the transverse portion of said envelope, a refleeting electrode at the end of said offset portion toward which said electrons are directed, a first resonator positioned between said reflecting electrode and the means providing said electromagnetic field, and other resonator means positioned between said first electrode and the transverse portion of said envelope, and including a second resonator for velocity modulating said electron stream and a third resonator for inductively extracting energy from said velocity modulated electrons.

5. An electron discharge device having cathode means for directing a stream of electrons along a beam path, a first electrode in said path toward which said electrons are directed, means for deflecting said stream at anangle to said path, means for velocity modulating said deflected electrons and returning said electrons along said first path toward said first electrode, and means for further velocity modulating said returned electrons and further means for extracting energy from said velocity modulated electron stream, and means for amplitude modulating said electron stream and including a pair of deflecting electrodes positioned between said last two means.

6. An electron discharge device having cathode means for directing a stream of electrons along a beam path, a first means in said path toward which said electrons are directed, means for deflecting said stream at an angle to said path, means for velocity modulating said electrons and returning said electrons along said first path toward said first means, resonator means for further velocity modulating said electrons and other resonator means for extracting energy from said velocity modulated electron stream, and means for amplitude modulating said electron stream and including a pair of deflecting electrodes positioned between said last two resonators.

7. An electron discharge device having cathode means for directing a stream of electrons along a beam path, a first means in said path toward which said electrons are directed, means for deflecting said stream at an angle to said path, means for velocity modulating said elecirons and returning said electrons along said first REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,450,265 Slepian Apr. 3, 1923 2,081,429 Gaede May 25, 1937 2,272,165

Varian et a1 Feb. 3, 1942