US2632127A - Electron apparatus for highfrequency performance - Google Patents

Description

March 17, 1953 H. M. WAGNER 2,

ELECTRON APPARATUS FOR HIGH-FREQUENCY PERFORMANCE Filed March 5, 1951 FIG.2

FIGA

IN V EN TOR.

HERBERT M. WAGNER Patented Mar. 17, 1953 UNITED STATES PA'E'NT E'FECE ELECTRON APPARATUS FOR HIGH- FREQUENCY PERFORMANCE (Granted under Title 35, U. S. Code (1952),

sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to improvements in methods and apparatus for controlling a beam of electrons.

Given two or more beams of electrons from as many different sources but all in the same tube, it has been demonstrated that due to the interaction of the space-charge fields of the respective currents in the beams, or due to interaction between the beams of electrons, it is possible to control one beam by varying the current in an adjacent beam. Examples of electron-discharge devices utilizing this basic principle are to be found in Patent No. 2,229,752 issued Janulary 28, 1941 to Jonker et a1. and in Patent No. 2,235,016 issued March 18, 1941 to Andrew V. Haeff. While these devices of the prior art have served a useful purpose, the respective operating characteristics thereof limit their scope of application; as in high-frequency operation.

One of the objects of the present invention resides in the provision of an improved electrondischarge device of the character referred to which has advantages over the various prior construction in the way of adaptability for application to uses wherein the operational frequency reached or maintained can be substantially higher than has been practical or possible heretofore. Another object resides in the provision of an improved tube of the character referred to where- .in there is provision for achieving substantially constant current output and/or transconductance and/or higher transconductance than has been practical or possible with the various methods and constructions proposed heretofore.

Other objects and advantages will hereinafter L appear.

In the drawing, the four figures thereof are simplified, schematic, sectional views of various constructions or arrangements and illustrate the operational action in as many cliiierent ways or methods of practicing the present invention.

In Fig. 1 of the drawing, the various parts or representations have been designated by the same respective reference numerals designating the electrons. Beam [4 may be modulated in intensity by a conventional control grid represented at Ma. On account of mutual repulsion between the two electron beams, changes of or variations in density of the first or controllin beam 14 caused or effected by changes of or variation in the input voltage impressed on grid Ma, effect corresponding deflections of the second or controlled beam l5. Deflection of beam l5 with respect to the bottom edge of a fixed, intercepting plate 15a results in conversion of such deflection into corresponding current changes or variations in current at an associated output plate or electrode l5b. For example, as the current or density in the controlling beam 14 increases, the mutual repulsion between the two beams becomes more pronounced and the controlled beam I5 is deflected accordingly, further away from the blocking or intercepting edge of plate i5a. This action permits more electrons to strike plate 15b whereupon the output current at the latter increases correspondingly. In lieu of plate l5a, an apertured plate may be used. In such case, the size, shape and position of the aperture would be such as to pass substantially the entire beam 15 with the latter directed horizontally in the normal, undeflected position shown.

Beams I l and I5 may be normally in different planes approximately parallel, at right angles, or at some intermediate angle to each other, and they may be pointed in the same general direction or in opposite directions.

For the purpose of obtaining phase-shift in high-frequency operation, it might be found desirable to shift beam M longitudinally with respect to beam [5.

In Fig. 1, the controlling beam [4 is represented as being a relatively narrow, ribbon' type beam. It may, however, be diffused and distributed over a relatively wide area. Other modifications or arrangements would reside in providing for other, additional beams similar to beam l5, all controlled in the same manner as the latter by the single controlling beam l4. To obtain an operational result just opposite to that in Fig. l, the plate l5a may be constructed so as to block the lower rather than the upper portion of beam 15. This may be done by designing the plate 15a to continue down toward plate l6 and to be provided with an aperture having an edge such that the upper portion of beam I5 is permitted to pass thru to reach plate l5b while the lower portion is blocked. In such case, as the current or density in the controlling beam [4 increases the mutual repulsion between the two beams becomes 3 more pronounced as before, but the controlled beam I5 is deflected downwardly and toward the blocking or interceptin edge of plate I5a. This action prevents or blocks more electrons from strikin plate I5b. The output current at plate I5b is therefore correspondingly less.

The cathodes at I9 and 5 may be at the same or at diiferent potentials. A metallic strip or plate I5c which may be integral with plate I5a, and a similar strip or plate I6, may be supported within the tube and disposed as shown'tdffmction as shields against the influence of magnetic fields or other disturbing factors external to the tube. The plates I5a, I50 and I6 may be connected together and be operated at the same potential.

In the arrangement shown in Fig. 2, the beam. Mb corresponds to the controlling beam M in Fig. 1, and there are two controlled beams I5d and I5e, each of the latter corresponding to the controlled beam I5 in Fig. 1. Supported at: the inner edges of beams I501 and I56 are the respective intercepting or blocking plates I511 and I5'e',

each of the latterserving the same purpose as the plate lid in Fig. 1. In operation, as the current in the controlling beam Mb increases the .mutual repulsion between beam Mb and the beams I541 and I5e becomes more pronounced and the'controlled beams I5d and I 5e are deflected accordingly, further away from the, plates I501 and I56. This action permits more electrons to strike the respective, associated anode plates I5 and I59, whereupon the output currents at the latter increase correspondingly.

The respective current outputs at plates Mb,

. I5 and I59 may be used separately or in combination. If the outputs Mb, 5 and I5g are in parallel, then the transconductance of beam Mb 'by grid-control at Ma, is augmented by the re- ,spective current increments due to the deflection of beams lid and I5e by beam Mb. Thus, a

means or method is provided for obtaining increased transconductance.

With the arrangement in Fig. 2 reversed, i. e.,

with the intercepting plates I 5d and I5e located .at the outer rather than at the inner edges of beams I56! and I5e, the operational result is just the opposite. In such case, as the current in the controlling beam Mb increases, the mutual repulsion between beam Mb and beams I5d and I 5e becomes more pronounced as before, but the controlled beams I5d and I5e are deflected further into the paths blocked by plates. I511 and I5e'. Fewer electrons are then permitted to pass and strike the respective, associated anode plates I5f and. I5g. The output currents at the latter therefore becomecorrespondingly lower, and if all out- Iputs are parallel, the transconductance and cur- ,rent charge at plates I5) and I59 subtract from such in beam Mb. This effect might be used to achieve constant current or transconductance by automatic utilization of the same if the current output of beam Mb or the tube transconductance exceeds a specified amount.

Considering another modification in Fig. 2, grids might be added to control the current in beams I50 and I5e, similarly to the grid Ma for controlling the current in beam Mb. Modulation of, current outputs Of beams I 5d and I 5e might then be efiected by applying voltages to 1 the respective grids for these beams and simultaneously with application of voltage to grid Ma.

' Modulation of beams I5d and I5e simultaneously would not cause any deflection of beam Mb, whereas modulation of beam Mb causes simul- '4 taneous deflection and consequent modulation, as explained, of beams I5d and I5e. Thus, isolation of controls is provided which might be useful for converter applications.

By interposing a single screen I! to function as an accelerating'anode and disposed as indicated, adjacent to the sources of beamsMb, IM and I5e, there is produced the condition of introducing the parallel beams, at equal electron velocities, into an enclosed, screened, field-free region so that deflection (or mutual repulsion) of the beams occurs in proper phase for deflection throughout the entire length of the path, to the respective output plates i db, I5f and I5g. In other words, throughout the entire length of all beams, the velocity of the electrons is the same, and constant. The electrons, therefore, are always in phase in any vertical plane along and common to the beams so that there is progressive and unidirectional deflection of the controlled beams I511 and I5e throughout their entire length, from source to current-output plate. This in-phase travel of the individual electrons in all beams would be important for operation at high frequency, such as of the order of 200 megacycles or higher. Contrary to this, and as is well known, the prior use of deflecting plates beyond a particular length of beam results in loss rather than gain in deflection-sensitivity. Such loss is attributed to electron phase-diflerences with respect to the modulating voltage across such deflecting plates.

From the above, it will be apparent that in the electron-beam-repulsion method or arrangement as in Figs. 1 and 2, there can be deflection over a long path with increase in sensitivity, but at no additional increase of circuit-capacity such as would result from lengthening the deflecting plates in a conventional tube design, In Fig. 2 the individual beams I5d and I5 may be replaced by a single, hollow, cylindrical beam whose longitudinal axis, undeflected, is coincident with that of beam Mb. In such case the source of the cylindrical beam might be an annular or circular ring provided with an emissive surface disposed in a plane perpendicular to the longitudinal axis of'beam Mb and with its center on such axis.

Serving the same purpose as the strips or plates I50 and IS in Fig. l, are the strips I8 and I9 which may be electrically connected to each other and to the plates I5d and I56".

In the method and arrangement illustrated in Fig. 3, modulation of beam I5h which corresponds to the controlled beam I5 in Fig. 1, is accomplished by deflection of the controlling beam Me by plates 20, rather than byuse of a grid for intensity-modulation of the controlling beam, as in Figs. 1 and 2. As beam Me is deflected with respect to a fixed interceptor or blocking plate Mc', there is a corresponding change in the density of this beam to the right of plate I lc or in other words, along that portion or length of beam Me which is adjacent to the controlled beam I5h. The operating action, otherwise, is the same as in Fig. 1, the current output at plate I5 varying in accordance with deflection of beam I5h with respect to the intercepting edge of plate I5h'. Strips or plates 2| and 22 may be employed, as in Figs. 1 and 2.

In Fig. 4, the operating action is first a control or modulation of beam I 4d by the grid Md, and consequent deflection of beam I52 with respect to the intercepting edge of plate I52, as in Fig. 1. The density of that portion of beam I52 to the right of plate I5i' changes accordingly, and

as a contro1 beam with respect to beam I57 and deflects the latter with respect to the intercepting edge of plate I59". That portion of beam I51 to the right of plate I57" new functions as a control beam with respect to the next beam [570 and deflects the latter with respect to the intercepting edge of plate lEk' to vary that portion of current in beam 15k which reaches the output electrode 23. This method or arrangement may be extended or continued in cascade fashion, to a larger number of beams for production of multiple-beam deflections. The tube shown in Fig. 4 is, in efiect, a deflection-multiplier, and Since succeeding deflections increase, an enormous gain can be realized through a series oibeam sta es. 7

In the respective arrangements shown in Figs. 1, 2, 3 and 4, there may be employed focusing electrodes of known types for forming sharp beams, if desired. While the various controlling and controlled beams have been shown to be narrow, one or more of the same may, instead, be diffused and distributed over a relatively wide area.

The drawing herein is not to scale, and the walls of the glass or metal bulb or envelope of the tube device may be considered spaced considerably more from the contained parts than might be apparent from the drawin For practical examples of details on structure and arrangement for the respective components of the improved apparatus herein as well as an explanation of the electron optics involved, reference is made to Encyclopedia on Cathode-Ray Oscilloscopes and Their Uses, by John F. Rider and Seymour D. Uslan, and published 1950 by John F. Rider, Publisher, Inc., 480 Canal Street, New York, N. Y., and to a text book by V. K. Zworykin et al. entitled Electron Optics and the Electron Microscope. and published 1945 by John Wiley 8: Sons, Inc, New York, N. Y.

One of the broader aspects of th present invention resides in the fact that change of current in the controlled beam is accomplished by mechanically blocking the flow of some of this beams electrons in amount corresponding to the controlled variation of current in the controlling beam or, as in Fig. 3, in at least part of the controlling beam. For example, by means of grid Na in Fig. 1, controlled variation of the current in beam [4 is effected, and by mechanical means such as the bottom, intercepting edge of the fixed plate la, more or less of th electrons of beam l5 are blocked and thereby prevented from striking the output plate [517.

In Figs. 1, 2, 3 and 4, the metal Strips or plates such as He, l6, 18, I9, and 22, respectively, establish the correct operating potentials. They also serve the additional, important purpose of shielding against otherwise troublesome effects of electrostatic charges on the walls of the envelope or bulb.

Although the output electrodes lbb, l5g, l5 and 23 have been shown as being in the form of conventional plates, they might be replaced by resonant cavities of known types; for use at the higher frequencies.

The basic principles involved in the present invention as well as several practical applications of the same, have been illustrated and described in a simplified manner for the purposes of those skilled in the art, but in addition to this it Will be apparent that there are possible numerous variations such as in the size, shape and arrangement of the parts without departing from this portion functions scribed, an envelope, means the spirit of the invention or the scope of the claims.

What is claimed is:

1. In the art of controlling a beam of electrons, the steps which consist in generating a first beam of electrons, generating a second beam of electrons adjacent to said first beam, causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, effecting controlled variation of the current in at least part of said first beam, and mechanically blocking the flow of some of the electrons of said second beam in amount corresponding to said variation.

2. In an electronic device of the character dedisposed within said envelope for generating a first beam of electrons, means disposed within said envelope for generating a second beam of electrons adjacent to said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, means associated with said first-named means for effecting controlled variation of the current in at least part of said first beam, and mechanical means disposed in said envelope in a possible path of fiow of said second-named electrons as determined by occurring current-variation in said first beam.

3. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed within said envelope for generating a second beam of electrons adjacent to said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, an output electrode, means associated with said first-named means for effecting controlled variation of the current in at least part of said first beam, and mechanical means disposed in said envelope between said second-named means and said electrode and in a possible path of fiow of said second-named electrons as determined by occurring current-variation in said first beam.

4. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed Within said envelope for generating a second beam of electrons adjacent to said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, an output electrode, means associated with said firstnamed means for efiecting controlled variation of the current in at least part of said first beam. and a plate disposed in said envelope between said second-named means and said electrode, said plate being arran ed with an edge thereof effective to block the fiow to said electrode of at least some of said second-named electrons as determined by occurring current-Variation in said first beam.

5. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed within said envelope for generating a second beam of electrons adjacent to said first beam and spaced from and substantially parallel with respect to the latter, means for causing said beams to travel a substantial distance in adjacent paths to provide acea-ret a cumulative mutual reaction between said beams during said travel, means associated withsaid first-named means for effecting controlled variation of the current in at least part of'said first beam, and mechanical means disposed in said envelope ina possible path of flow of said second-named electrons as determined by occurring current variation in said first beam.

6; In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed within said envelope for generating a second beam of electrons adjacent to said first, beam and spaced from and substantially parallel to the latter, means for causin said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during Said travel, an output electrode, grid means associated with said first-named means for eifecting controlled variation of the current in at least part ofsaid first beam, and a plate disposed in said envelope between said second-named means and said electrode, said plate being arranged with an edge thereof effective to block the fiow to said electrode of at least some of said second-namedelectrons as determined by occurring currentvariation in said first beam.

'7. In an electronic device of the character described, an envelope, an output electrode, means disposed within said envelope for generating a first, beam of electrons, means disposed within said envelope for generating a second beam of electrons directed at said electrode and disposed adjacent to said first beam for mutual repulsion eifect betweenv said beams, means for causing said. beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beamsduring said travel, means associated with said first-named means for effecting density-increase of said first beam to increase said efiect, and mechanical means disposed in said envelope between said secondnamed means and said electrode and in a possible path of flow of said second-named elec trons as determined by occurring current-variation in said first beam.

8. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed within said envelope for gen-- erating a plurality of beams of electrons spaced from each other and from said first beam and substantially parallel to the latter, means for causing said beams to travel a substantial distance in adjacent paths to provide between said first beam of electrons and said plurality of said beams of electrons cumulative mutual reaction during said travel, individual output electrodes for'the respective beams, means associated with said first-named means for effecting controlled variation of the current in said first beam, and plates disposed in said envelope between said second-named means and certain of said electrodes, said plates being arranged with edges thereof effective to block the flow to said certain electrodes of atleast some of said second-named electrons as determined by occurring currentvariation in said first beam.

9. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, a first-interceptor plate, means for deflecting said beam with respect to an edge of said plate, an output electrode, means disposed Within said en- 8 velope for generating second beam of" electrons adjacent and substantially parallel to said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, and a second interceptor plate disposed with an edge thereof in the path of said second beam.

10. In an electronic device of the character described, an envelope, means disposed in said envelope for generating a series of electron beams substantially parallel and spaced with respect to each other and with adjacent beams in said series disposed for mutual-repulsion effect with respect to each other, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, means for effecting variation in density of the first beam in said series, and individual and mechanical means disposed respectively in the paths of the remaining beams for blocking the latter in amounts varying in accordance with the occurring magnitudes of beam-deflection induced by said mutual-repulsion efiect.

11. In the art of controlling a beam of electrons, the steps which consist in generating a first electron beam and a plurality of electron beams, disposed about and each substantially parallel to andspaced from said first beam and each disposed for mutual-repulsion efiect be tween itself and said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel,

ing said beam, mechanically blocking said beamin amount corresponding to the magnitude. of deflection thereof, generatinga second electron beam adjacent to said first beam and exposed to the eifect of mutual-repulsion between itself. and said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams. during said travel, and mechanically blocking said second beam inamount corresponding to the magnitude of deflection thereof by virtue of said mutual-repulsion effect;

13. In the art of controlling a beam Off-3160- trons, generating a spaced from and substantially parallel to each. other and each exposed to theefiect of mutualrepulsion between itself and an adjacentbeam, varying the density of the first beam in said series to cause deflection of the other beams in cascade fashion, and blocking said other beams individually and mechanically and inamounts varying respectively and-in accordance. with the respective magnitudes of beam-deflection induced by said mutual-repulsion efiect;

14. In the art of controlling a. beamof electrons, the steps which consist ingenerating a firstefiecting controlled variation of. the currentin:

series. of electron beams at least part of said first beam, and blocking the flow of some of the electrons of said second beam in amount corresponding to said variation.

15. In an electronic device of the character described, an envelope, means disposed within said envelope for generating a first beam of electrons, means disposed within said envelope for generating a second beam of electrons adjacent to said first beam, means for causing said beams to travel a substantial distance in adjacent paths to provide a cumulative mutual reaction between said beams during said travel, means associated with said first-named means for efiecting controlled variation of the current in at least part of said first beam, and means disposed in said envelope in a possible path of new of said secondnamed electrons as determined by occurring current-variation in said first beam.

HERBERT M. WAGNER.

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

UNITED STATES PATENTS Number Name Date 2,179,205 Toulon Nov. 7, 1939 2,307,693 Linder Jan. 5, 1943 2,403,562 Smith July 9, 1946 2,416,914 Eaton Mar. 4, 1947 2,449,339 Sziklai Sept. 14, 1948 2,454,652 Iams et a1 Nov. 23, 1948 2,472,779 Selgin June 7, 1949

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