US2603764A - Centimeter wave velocity modulated electron discharge device - Google Patents

Description

4July 15, 1952 E. Ros'rAs CENTIMETER WAVE VELOCITY MODULATED ELECTRON DISCHARGE DEVICE Filed may 2'1, 1947 2 SHEETS-SHEET 1 IIIIV FIG.

Illvm FIG, 4

| Ul I I I I *i FIG. 3

FIG.

FIG.

IN VEN TOR.

ERN EST R OSTAS A TTOPNEV FIG. I

`)uly 15, 1952 E. Ros'rAs 2,603,764

CENTIMEITER WAVE VELOCITY MODULATED ELECTRON DISCHARGE DEVICE Filed May 21, 1947 2 SHEETS- Smm 2 s llilllllllj 7| 7069 84 7 lll-NA IN VEN TOR. ERNEST ROSTAS.

A TTORNEV 7 FIG. 9

Patented July 15, 1952 CENTIMETER WAVE VELOCITY MODULATED ELECTRON DISCHARGE DEVICE i' Ernest Rostas', Paris, France, assignorv to Intervnational Standard Electric Corporation, New York, N. Y.,`a corporation of Delaware I Application May 21, 1947, serial No. '149,511 In France June 15, 1939 -ASectionvL Public Law 690, August 3, 1946 Patent expires `lune 15, 1959 The present invention relates to means for the control of electronic discharges and devices making use of such means.

These means and devices are particularly applicable vto high frequencies corresponding to wavelengths of the nature of a meter and a centimeter down to a'few millimeters.

' The invention has in particular for one of its objects the provision of means whereby the electrons oigan electronic discharge may be sep- .aratedsubstantiallyinto two groups of distinct mean transversal velocities in accordance'with a desired law of control. Y

' Another object of the' invention is 'the provision of means whereby one of these groups vof :electrons of differing mean transversal velocities `may be vused as desired with a view to extracting Aenergy from the selected group in an..out going circuit.

The term transversal velocity of the electrons is understood to mean the perpendicular velocity component in the magnetic field used;

lOther objects of the invention further rest in the design of the structure of the electronic discharge devices making use of a controlled separation of the electrons of a discharger as also the ymeansV for the .production of an .electronic discharge whose structure Awould be particularly favourable in order that this separationfmight be realised. 'l f.. In 'accordance with certain of its characteristics, the invention provides for controlled means of separation of electrons in accordance with .their transversal'velocities,comprising a magnetic field directed along the 'general axis yof the electronic discharge beam and a high frequency electric field with a direction which is substantially perpendicular to the axis of the 'said beam.

In accordance with another characteristic. of the invention, the electronic beam used does not 'consist substantially lof electrons whose direction of ldisplacement, is along the axis'of the beam.'.

In accordance with another characteristic of iifclaims. (C1. sis-:6r

theLinvention, means are. provided to eliminate l `according to their absolute tangential velocity by means of, for example, reflection electrodes.

InA accordance with other characteristics of the invention, the electronic discharge devices comprise two or more distinct regionswhich' are traversed in succession by a single beam of electrons, a magnetic field being directed in accordance with kthe axis of rthis beam and an electric high frequency eld traversing each of the said regions following a direction vwhich islsubstantially perpendicular to the axis of the said beam.

In accordance with other characteristics 'of the invention, the electronic discharge devices comprise. two or more distinct regions traversed in succession by a single beam of electrons not including electrons which shift alongv the axis of the beam at the entry to the first region, a magnetic field being provided parallel to the axis fof the said beam and the high frequency electric elds substantially perpendicular tothe axis of the said beam individually associated with thev said regions.

In accordance with other characteristics of the invention, the electronic discharge devices comprise a first region in which an electron beam penetrates which does .not have any electrons whose .direction of shift is strictly parallel to the axis of the said beam for the input of the said volume, a magnetic field directed along the axis of the beam and ahigh frequency electric eldsubstantially perpendicular to the axis of the said-'beam traversing this region, means for selection Vat the output of the said region of'one of the'two groups of electrons which are'forme'd there, and a second region traversed by selected electrons, a high frequency electric fieldV being provided in this region transversally with relation to the axis of the electron beam'selected and a magnetic field following the axis-of the beam which may be the same magnetic -eld as that which traverses'theiirst region.v

In accordance with other characteristics of the invention, the electronic discharge'devices comprise means for the generation of a' conic beam of` electrons without axial electrons,A this beam converging'substantially towards the inputof a region in which a magnetic field isA provided in the axis of the beam and a high frequency electric field substantially perpendicular to this axis, means at the output of this region for the elimination of electrons fromone of the two groups being produced whilst theregion is traversed, a second region equally provided with a high frequency electric eld which is transversal Ato the axisof the electron beam which is not eliminated, and also crossed by an axial magnetic eld which can be the same as that which crosses vthe iirst region, and means for the collection of the electrons at the output of the said second region.

in' which the devices lareus'ed'; Y

In accordance with yet other characteristics of the invention, electronic discharge devices in- Y 4clude means forAv generating a beam `of electrons,

means modifying. the transversal velocities of the electronsof the beam'with a View toproducing two groups of differing mean transversal veof a beam into two groups of electrons of varying l transversal velocities Will be explained with referlocities, means for the elimination of one of thesel I' groups of electrons, and for vthe use and collection of the electrons of the remaining group; In accordance with anothencl'iaracteristic of the invention, means for thegenerationof a confie` cal beam Where thereis a converging of electrons substantially focussed on the input of the rst ence to Figs. l, 2 and 3. This system comprises a 'pair of `parallel conducting plates l and 2 bei tween which a beam of electrons 3 is transmitted.

i force are indicated at E and provided with arrows A high frequency electric field whose lines of Y vindicating the instantaneous direction of the eld modifying unit of the transversall velocities of the electrons, consist in an emissive electrode and an electronic concentration lens.

In accordance with another characteristic 'of the invention, means for the eliminationof one of thef'groups of electrons according v:to their transversal speed consist in a diaphragm collect -ing all the electrons whose transversal speeds are vgreater .than acertainivalue..

' In accordancewith'another characteristic-.of

'the invention, means vforthe elimination .of one -of the-groups'ofelectrons according to their transversal velocities consist in aireecting electrode .which only permits the-free transmission to electrons of transversal velocities greater than ,a certain.velocity and reiiecting the electrons of lower velocities in their `'direction Vof arrival, orlif desired, in a different direction.

In accordance with yet other characteristics; of the invention,l several beams of electrons lnothav- A-ing axial electronsjvhen they vare generated arev sent parallel in the same direction, or in opposite directions across regions such asthe above-'inem tioned. I

According to yet other characteristics-the invention provides devices4 such. as those Aabove. de-

scribed, fparticularly'adapted to be associated as oscillatorsfrepeaters,detectors'etc. in systems for thetransmission of Waves'iby dielectric guides.`

:The invention will be explained in detail in the following' descriptioni based onl the attachedK drawingsinwhichi f Figs. l and 2 diagrammatic'ally represent in longitudinal andr transversesections respectively a devicej modifying the` transversal velocities of 'the electrons inY such awayv as `:to obtain *two groups of! electrons of diiferingfvelocities, Fig. 3 indicating the examples offthe `paths of --trons at .the output of this device; 'j Fig. 1 4-v showspdiagrammatically an example` 'of the discharge device incorporatingv certain characteristics of'theinven'tion with; means-for the the siecelimination ,of theelectronsof greater transversal velocities;yandfof 'using the electrons...with low velocities; f f Y' ,'Fig. 5 Ashows,diagrarnmatically in transverse vsection the paths'-oflthejelectrons in the system according to,v the Yinvention .,Figzl 6`shows-diagrammatically an example of Y vthe discharge deviceincorporating certain characteristics of the invention with means fora the Aeliininaticnzfof theelectrons of lesser :transversal A'velocities and'of using the electrons ofhigh transversalrvelocities; y 4 Y Y y,

,Fig. 7 showsl diagrammatically an example of the'v structure -forthe'generation ofa-v beam of electrons, particularly suitable for usein the devices of the present invention; Vand l Figs. 8, 9 and l0 show in lateral view, in part in section, in elevation in section, and in detailed view an example of an embodiment ofthe device is applied between these plates. The. electrons move, 'as shown, following a helicoidal path which will be inscribed on a cylinder of a conv stant radius if they are only subjected to a magvrinstant may have a transversal velocityfwhich is such that it is ready to follow one ofthe circular paths 5, 6, Vl or 8. -If the electronxhad a velocity which was such;that itfollowed the path 5 of the'electric iield, it wouldberetarded at a considered moment'where the electric 4field Was in the instantaneous direction represented by the arrows of the lines. of force. E, and it would describe inthis case a path offa smallenradius. When it traverses at 18,0,of itspath; it `would again be retarded ,sincetheelectric :fields-.Would not rthen be inversed, and so on 'in the periods following. In this way. such VanI electron kwould follow in its passage between the plates l 'and 42 a path suchas shownat 9 in Fig. 3. If, onthe other hand, the electron had a transversal velocity such that it followedunderthe action ofthe magnetic field only, thepath6, `itfwould be accelerated `by the electric vield periodically with each so that it Ywould ,describe a total. path during its passage `between the plates il and2 such assh'own in Hl on Fig'. 3. If itisito follow one of the paths I and 8, it'will be alternately accelerated and retarded Witheach 180 or vice versa, lso that' its transversal velocity will notlin practice be affected Von an average bythe existence of the electric field. i

The operation of the system of invention, will therefore, resultin the production of two relatively distinct electron beams, one of accelerated lOnthis figure simultaneouspaths I6, I1 and I8 of electrons I9; 2! and 2i have been shown. These paths are circles andthe electrons have all been indicated in the same positions with relation'to these paths-that is to say, above their paths in the case shown. These electrons all turn in the direction indicated by arrows 22' and will be sub,- ject to lalternative transversal shifts such as `indif cated by the double arrows 2.3, these alternating shifts'being co-phased and in consequence the entire cloud of electrons 'will oscillate between plates Iland I5, thus losing the energy which will be collected by the said plate inthe form of oscillatory energy which will be used in' a.

circuit not shown, connected to these plates. Their'paths will in consequence be more and more narrowed as shown at 24 in Figs. 4 and 6 and will be finally received by an'electrode or System of electrodes provided for this purpose and dia'grammatically shown at 25 on these two gures. This'electrode 25 may be brought to a potential which is such that the electrons are retarded and received at a very reduced velocity with a view to decreasing the power consumption of the device.

The devices in the twoAk Figures 4 and 6 only differ, moreover, by the group of electrons selected forutilisation. The modification systems of the transversal velocities ofthe electrons and 4 between the two pairs of parallell plates I--2 and I4-I5, the potential of this cylinder being negative with relation to the pair of plates I 2. The reflected electrons may return-in the opposite direction in their direction of arrival, as shown at 28 in Fig. 6, or the reflection electrode may be arranged at a certain angle to the general direction of the electronic beam leaving plates l.-2 so asto send the reected electrons outside the space between the plates. f

In the devices in accordance with the invention, equally the magnetic eld should be provided along the entire length of the structure and not simply between the plates I and y2.

AIt should be noted that in the case where the reflected electrons are transmitted between plates I and 2 they create in some degree a reactance or return feed of electrons. Such a reactance may be provided if desired by transmitting a beam of electrons between the plates I4 and I5 Vso that the two plate systems serve simultaneously for input structures and for use yat the device. f

The means for generating the beam have not been considered up to the present. If the'beam ,of electrons transmitted between the plates I and 2 is in its origin a parallel beam, all the electrons willbe subjected to a transverse acceleration at the expense of the'energybf the high frequency eld. It is, consequently, necessaryto use a conical electron beam which has no .elec- Atrons which move. axially when they enter' the pole-piece of theelectromagnet or magnet creatv ing `the magnetic field H. This electroae',lortl'iis pole-piece, concentrates the electrons emittedby the electrode 29 into `a hollowc'onical beam 3| which converges approximately on tothe input of the plates I-2. Between fthe platesl and 2 this beam takes the' form indicated at'3 on the Fig.l. f

On this Fig. 7 by way of illustration the electric connections of the electrodes 28, 30 and I'-2 have been shown with relation to a source S.

l vThe devices of the present invention maybe arranged to operate either as oscillatorsor` as detectors, demodulators, repeaters, Ufrequency changers etc. They maybe incorporated in ultra short-wave transmission systems, for example, they may with advantage be applied in systems for the transmission of waves by dielectric guides. An embodiment of the device ci this kind whose structure is' arranged for adaptation in a 4transmission system with dielectric guides is vshown in Figs. 8, 9 and l0.

In these gures an external sheath which is of metal in the example chosen, butwhich may equally be of insulating material, is of such a form that it has four open extremities, two'by two opposite to one another, 5I--52 and 513-154'. These extremities are of a suitable vform and dimensions to be adapted to the ends 'cfdielectric guides, shown here for greater simplicity in the form of a cylinder with a circular section', although they may have any desired straight section usual in the art of dielectric guides, that is to say, they may be elipsoidal, oval,square, rectangular, polygonal etc. The connections between the extremities 5I-54 of the external sheath 5f) and the sections of the guide, of vwhich two only are shown cn the right-hand side of the design, thus and 5B are constructed So -as to be airtight, for example, as shown by means of ,the insulating junction tubes 5'! and 58 sealed at the two extremities on the metallic extremities adjacent to the sheath, and the guide sections, Aand provided withv dielectric transversal airtight cellular constructions such as 59. These Y cellular constructions may either be of one piece '.ample, by pulverisation or projection, or any other suitable manner, and which is shown at on the design on each side of the transversal cellular constructions. I I

Two metallic tubes 6I and 62 open lat either lend are arranged inside the sheath between` the extremities 5I-52 and v53-54v respectively,and are heldin place by the insertion of their extremities inside enclosed portions 5Il54 of the external sheath. These ends may be split as shown at 63 to permit of freer expansion or contraction under the influence of temperature fluctuations. Thesemetallic tubes 6I and 62 are pierced with apertures 64--65 and 66-61 which chanically'and electrically.

lar constructions,

acca-,764

diaphragmzmaypreferably be also electrically an integral part Yof V the nlament 69. Thesev-.electrodesia'recarried by the cylinderV 6l through the mediuln'of the insulating rings '12 and 'I3 on which the conductor rings 14 andr 'I5 are threadedi to Ywhich'latterithe electrodes are fitted me- The cylinder 68 is carried by its own electric connection 16, Fig. 9.

Onthe side of the external opening 61 to the cylinder 62 a collector electrode 'l1 is placed for the. electronic beam which transversesin succession the volume 6|V through the openings 64 and 65; the conductorv cylinder-68 and the volume 52. across the openings 66 and 61. This collector electrodev 'Vl' is preferably supported by its electric connectionA 'i8 which crosses the sheath 50 in such a way as to be electrically insulated;

f Asmay be seen on Fig. 9, the electric screen 10, theA lament 69 and the diaphragm -ll are mechanically spaced by insulating cross-pieces 19.

A magnetic field parallel to the general direction of the electronic beam emitted by the filament is obtained by means, for example, of an `el'ectrornagnet Whose pole-pieces are indicated at 80 and 8 I. v A device of this kind operating inthe manner explained with regard to Fig. 6 may in particular be used in a system for the transmission of waves bydielectric guides. For this purpose a section of the'incoming guide is assumed to be connected to the end I of the device and a section of the outgoing guideis shown at 56. In these guide sections the waves arrive in the device by the en'dllfv4 as shown by the arrow 82 and leaveyby the extremity 56 as shown by the arrow 83. Conductor pistons 84 and 85 reflecting the waves are provided in the other guide sections with a View to ,adjusting the agreement of the volumes by the sliding motion of the pistons. 'I'hese pistons arelprefe'rably in the portions'of the device in which Vthe vacuum is notV made, but which are ,.lled by a'gaseous dielectric; for exam-ple, with air. "The vacuum is only ensured inside the sheath up to the transversal dielectric celluthe conducting continuity beingrealised as nearly as possible between the cylinders 6| and 62 and the sections of the dielectric guide by conducting coatings 6D. y

Y In order to use the oscillator device a reflecting piston isfalso provided in the guide connected to the end 5| and the return coupling of the energy of the high frequency Waves necessary for the V,creation andmaintenance of the oscillations is ensured, for example, by a connection with lecher r wires'e terminated by two loops 81 and 88 or in any other suitable manner, for example, by a dielectric guide section. Y

Another means of return coupling may consist in accordance with another characteristic of the Ainventionin a beam of electrons crossing the v two spaces 62 and Bl in the opposite direction of with relation to the beam and to the volumes,V as

shown schematically at 89. y

f In order. to use thedevice shown asy an amplia ier on the other hand the return feed circuit 86 may; or may not be-suppressed, and the incomingwaves are transmitted-.in the direction sho-wn by the arrow- 82,- and go outas shown by the arrow.- Y l A device of this-kind may also' be usedesja detector, or demodulator by transmitting the modulated carrier wavesV in the device Yin 4thedirection of 'the arrow 82, and by collecting jthe demodulated or detected Vwaves on the electrode Tl. The potentials of the electrodes are adjusted in such a manner as toensure detection; for example, the electrode r'I7 may be connectedv tothe cathode :through a resistance making use of the demodulation'products, f

In order to use the tube as a modulator Vthe diaphragm 'H is disconnected from the filament and/fed by a modulating potential which, corr-- sequently, modulates the intensity of the-cathode beam-.emitted by the filament.

A `feed circuit of ythe electrodes of thel device described has been shown by way of example in the case oi operation as an amplier. The reilector cylinder 63' isy connected to a Vnegative point of theY batteriy'lik of which another point-y less negative,v is connected to the filament. 'I'he positiveYV end of the'battery Si! is connected in *parallel tothe two cylinders El and 62Y and a Ypositive intermediary point of the battery i's connected to the collector electrode ''Ifwith a view to retarding the electrons in the utilisation'cylinder B2' and to collecting them lwith a very re'- duced velocity which diminishes the losses in energy of theA structure. VA Yiilament heating battery 9l` is shown' connected to a point'of the screen 'mand al pointof the filament 69. YA11 the Vfeed leads of` the generator and collecting electrodes of the beam are insulatedin the external sheath as also'the cylinderl when the potential of the cylinders 6l and 52 is directly applied to the sheath 50 vvsince this latter is assumed to be metallic in the case shown.Y The guide section' 56 may obviously terminate if` desired by a wave radiator system inspace, or in Waves, or in incoming Waves which may originate in a collector system of waves radiated in space. Y

Althoughv the inventionV has been described With regard to vcertain particulerembodimentsit is clear that itisv not in the least limited to these, but is on the contrary capable jofjnfumerous modifflcations and adai'atations;y withoutvleaving. its

domain. i i

Ircl'aim: f "fp j 1. An electron discharge device includingY a source of electrons for projecting a'stream ,y of Y electrons in a path, means about said path adjacent said 'source forV generating an alternating kelectric eld substantially transverse to the flow of electrons from said source, means about said tpathiorV producing a magnetic field extending generally longitudinally of said flow Vof electrons from said source, a first electrostatic means about said path adjacent said alternating eld generating means for preventing the passa-ge of some of the electrons in said now, and a second electrostatic means about said path adjacent said first electrostatic means for extracting alternating energy from the electrons which pass said iirst electrostatic means.

v2. An electron discharge device according' to claim l, in which saidmeans for generating an alternating electric eld includes a cavity resonatorresonant at the operating frequency disposed in communication with said path between said source and said iirst electrostatic means.

3. An electron discharge device according to claim 2, in which said second electrostatic means includes a cavity resonator resonant at the operating frequency disposed in communication with said path adjacent said first electrostatic means. f

4. An electron discharge devicev according to claim 3, in which coupling means are provided for feeding back energy from said electrostatic energy extraction means to said electric field generating means.

5. An electron discharge device according to claim 4, in which said coupling is made by means of lecher Wires coupled between said cavity resonators.

6. An electron discharge device according to claim 1, in which said electrostatic means for preventing the passage of some of the electrons in-V cludes a diaphragm frame disposed generally normal to the iiow of electrons and' having an aperture generally coaxialwith the iiow of electrons and coupled to a source of potential negative with respect to the potential of said energy extracting means.

7. An electron discharge `device according to claim 1, in which said electrostatic means for preventing the passage of some of the electrons includes a hollow cylindrical member extending generally longitudinally of and coaxial with the flow of electrons and coupled to a source of potential negative with respect to the potential of said energy extracting means.

8. An electron discharge device according to claim 1, in which said source of electrons includes means connected thereto for modulating the output of electrons from said source in accordance with a modulating signal.

9. An electron discharge device according to claim 5, in which said cavity resonators are portions of input and output hollow conducting wave guides, each having apertures generally concentric with the flow of electrons to permit such iiow.

10. An electron discharge device according to claim 9, in which adjustable means are provided in said cavity resonators for adjustably varying the oscillating characteristicsof said resonators.

11. An electron discharge device according to claim 10, in which said adjustable means includes a plunger or piston adjustably slidable Within one of said resonators.

12. An electron discharge device comprising a pair of high frequency electromagnetic Wave guides disposed in adjacent relation, a housing enclosing corresponding lengths of said guides, said guides having aligned apertures therethrough, an electron emitter and an electron collector in said housing disposed in spaced relation on opposite sides of said guides and in alignment with said apertures to define an electron beam path transversely of said guides, means to produce a magnetic eld axially of said beam path, an annular electrode disposed in said housing between said guides and means to bias said annular electrode at a potential to cause certain claim 12,'further including means to terminate eachof said guides to one side of said apertures. 14. An electron discharge device according to claim 12, further including lecher wires coupling said guides for return flow of energy vtherebetween.

ERNEST ROSTAS.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS

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