US2939998A - Direct radiation vacuum tube - Google Patents

Direct radiation vacuum tube Download PDF

Info

Publication number
US2939998A
US2939998A US678606A US67860657A US2939998A US 2939998 A US2939998 A US 2939998A US 678606 A US678606 A US 678606A US 67860657 A US67860657 A US 67860657A US 2939998 A US2939998 A US 2939998A
Authority
US
United States
Prior art keywords
structure
electrical structure
vacuum tube
stream
electron
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
US678606A
Inventor
Winfield W Salisbury
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.)
Zenith Electronics LLC
Original Assignee
Zenith Electronics LLC
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 Zenith Electronics LLC filed Critical Zenith Electronics LLC
Priority to US678606A priority Critical patent/US2939998A/en
Application granted granted Critical
Publication of US2939998A publication Critical patent/US2939998A/en
Anticipated expiration legal-status Critical
Application status is Expired - Lifetime legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J25/00Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
    • H01J25/34Travelling-wave tubes; Tubes in which a travelling wave is simulated at spaced gaps
    • H01J25/36Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and without magnet system producing an H-field crossing the E-field
    • H01J25/38Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and without magnet system producing an H-field crossing the E-field the forward travelling wave being utilised

Description

W. W. SALISBURY DIRECT RADIATION VACUUM TUBE June 7, 1960 2 Sheets$heet 1 Filed Aug. 16, 1957 w. w. SALISBURY 2,939,998 DIRECT RADIATION VACUUM TUBE 2 Sheets-Sheet 2 June 7, 1960 Filed Aug. 16, 1957 ilnited States Patent F DIRECT RADIATION VACUUM TUBE Winfield W. Salisbury, Palo Alto, Calif., assignor to Zenith Radio Corporation, a corporation of Deiaware Filed Aug. 16, 1957, Ser. No. 678,606

11 Claims. (Cl. 315-4) This invention relates generally to a direct radiation vacuum tube apparatus and more particularly to a direct radiation vacuum apparatus in which an electron stream is projected to interact with an electromagnetic field supported by an electrical structure to produce radiation.

In my copending application Serial No. 533,098, filed September 8, 1955, and entitled Electromagnetic Wave Generator, which issued as U.S. Patent No. 2,866,917 on December 30, 1958, there is described a generator in which oscillation and radiation is produced coherently over an area of many square wavelengths. An electron stream is projected through and interacts with an electromagnetic field which is supported by a periodic structure. Energy of translation of the electron stream is transferred to the electromagnetic field and serves to increase its intensity. The field radiates into space.

It is an object of the present invention to provide a direct radiation vacuum tube apparatus in which the interaction region is shielded from external electric fields.

This and other objects of the invention will become more apparent from the following description when read in conjunction with the accompanying drawings.

Referring to the drawings:

Figure 1 is a perspective view of a direct radiation vacuum tube constructed in accordance with my invention;

Figure 2 is a cross-sectional view of a direct radiation vacuum tube;

Figure 3 is a view taken along the line 33 of Figure 2;

Figure 4 is an elevationalview partly in section of another direct radiation vacuum tube;

Figure 5 is a view taken along the line 5-5 of Figure 4; and

Figure 6 is an enlarged view of a portion of an electrical structure which may be used in a direct radiation vacuum tube.

Electrical structures which support traveling electromagnetic waves having a phase and group velocity of various values are well known. For example, a series of resonant slots or open-ended cavities coupled together by means of their stray fields are capable of supporting a traveling electromagnetic wave which supports a phase velocity greater than the velocity of light in free space.

An electromagnetic beam is regarded as a moving ionosphere. Such a stream is capable of supporting magneto-hydro-dynamic or space charge waves which have phase velocities with respect to a stationary system which are greater than the velocity of light.

If an electron stream is projected through a traveling electromagnetic wave, there is interaction between the wave and the electrons. If the phase velocities of the wave and the electron stream are near one another, the conditions are suitable for amplification of the wave by conversion of energy of translation of the electrons to electromagnetic wave energy.

At various points along the wavethe electric field components of the wave will alternate in direction, tend- 2,939,998 Patented June 7, 1960 ing to accelerate the electrons in the stream and a half wavelength later to decelerate the electrons. Electrons moving along with the accelerated fields speed up with respect to the mean velocity of the stream, while those which are moving in fields of decelerating fields tend to slow down. The net elfect of the interaction is to cause bunching of the electrons. If theelectron stream is sup? porting a phase velocity which is slightly greater than the phase velocity of the electromagnetic wave, the" electron bunches in the stream will eventually move toward regions of decelerating fields. This causes theelectron stream to slow down and lose kinetic energy whichis trans; ferred to the electromagnetic wave to amplify the same. The direct radiation tube is not dependent, however,,.on physical bunching of electrons since all parts of the radi, ating structure contribute simultaneously to aslngle radiated wave front. It is sutficient to achieve coherent radiation that widely spaced electrons have the same relative position and approach to similar parts of the repetitive supporting structure at the same time. This phenomenon, which may be referred to generically as phase bunching of the electrons, is particularly significant at extremely high frequencies, at which the electron density per wavelength is so small as to preclude appreciable physical bunching of electrons within anygiven wavelength. I I The energy of translation which is transferred to the electromagnetic wave is in effect transferred to the slots, cavities or other configurations of the electrical structure and serves to build up the stray fields supported thereby. The slots, cavities, etc., of the electrical structure then radiate into free space. The angle of the radiation is such that the projection of the phase velocity vector on that angle is equal to the velocity of light.

The frequency or radiation depends upon the velocityof the electron stream, the configurations of the electrical structure, and the mode which is being excited and amplified.

.The cavities or slots may degenerate into mere scratches like those of a difiration grating. The direction of radiation is then the same as that of the first order spectrum for the grating at the wavelength produced.

If stray field coupling between the various elements which form the electrical structure is insufiicient, it may be increased by well known means. For example, slots or holes may be employed to couple the resonators or cavities together. Slots or holes may also be employed to control the group and phase velocity of the electromagnetic wave.

The Q of the system may be increased by providing means to intensify the standing wave pattern at the operating frequency. This may be accomplished by placing a partial reflector perpendicular to the direction of radiation which sets up a standing wave pattern between the refiector and the electrical structure. 7

As described in the copending application, the radiations produced by a system of the above character arein phase along the radiation wave front and are, therefore, coherent radiation as contrasted to that of a thermal source such as a heated black body which produces incoherent radiation. The disadvantage with incoherent radiation is that although it may be focused, the intensity of the image may never be greater than the intensity of the source. With coherent radiation, the radiation may be concentrated into an image which is more intense than the radiating surface by the ratio of the area of the source to the area of the image. Theoretically, the limiting reduced size of the image is M2. Practically, the limiting size of the image is determined by the difiraction effect of the size of the surface of origin measured in wavelengths, provided that no small aperture intervenes to intercept the rays.

, predetermined values.

adjacent the structure to interact with the wave and: 'is' a'g'e applied to dle electrical structure.

Referring now to the drawings, 1 have shown electrical structures which are capable of supporting traveling electromagnetic waves having phase and group velocities of An electron stream is projected collected to a collector; As a resul't'of the interaction the have isannplified. The wave radiates coherently at an angle whichdepends "on the frequency of operation. .A 'pafriai reflector may be' employed to increase the Q of the J A lens f'sy'st'em may be employed to direct the energy to a. desired pattern. offpr'edete'rrrnned intensity. lnja'ccordance withrlre in ennon, the electrical structure is "shielde'd'frorn external electric fields and a decelerating produced between "the, Structure and the collector thei'ebyfeiitract-energy the high velocity electron -leaving the interaction region. 'Reirringgparticularly to Figural, a schematic perspective view-er a direct radiation vacuum tube is shown. A "suitable electron I1 serves to project a parallel elec- Thebe'am is'accele'rated, as willbe presentl'ydescribed, and passes adjacent and parallel to the sur- T'a'c'eofthe electrical structure '13. It is then intercepted the collector 14. A suitable gun is described in Pierce, Theory Design of Electron. Beams (D. Van Nostrand Co Inc), pages 173-180.

The electrical structure 13 is surrounded by dielectric material 16 which is transparent to the energy being The outer surfaces '17 of the dielectric material m niacs conductive to provide shielding of the structure from electric fields. For example, the outer surface may be coated by a very thin "metallic layer such as may be produced by evaporation and which transmits a large percent-age of the radiation. The dielectric material may alo=comprisetransparent conductive glass'orpiastic. A space 18 exists in the 'rnaterial 16 through which the elecbeam 12 may pass. Bringing or penetration of the electric fields into the space 18 is very slight. If desired,

' grids 21 and 22 may be provided to further prevent any penetration of electric fields into space 18. The electrical 13 comprises a plate having parallel slots 23 formed therein. The slots'a're spaced whereby their stray fields couple them together. A structure of this type supa travelling electromagnetic wave as previously which permits evacuation of the same. The tube is then and the structure supports'i'a travelling electromagnetic wave. The stream 38 is.,projected adjacent the grooves 37 and passes through the electromagnetic wave to interact therewith and amplifythe same. Surrounding the electrical structure 35 is a transparent dielectric member 41. The surface of the member 41 is coated by a conduetive transparent material 42ypreviously described. The member which surrounds the electrical structure serves merely to shield the same from external electrical fields.

.As previously described, energy is radiated at an angle. Tofincre'a'se the "Q oft'h'e system, a partially reflecting surface is placed in the pathof radiation and perpendicular thereto. sets up standing "waves at the omra-ting frequency. the l'en's ,44 has a surface 46 which is partially reflecting. A portion of the radiation is reflectedto increase magnitude of the standing waves while the the remainder passes through the lens and is lenses, it is possible focused thereby. -A second iens 4-7 is employed to further focus the energy to provide an image of desired size at a predetermined distance. It is apparent that by properly selecting the lens system or by varying the position of .the

image. It is to be understood that although a particular lens system has been described, any suitable lens system may be employed.

'The electron gun, collector, electrical structure, and

40 lens system'are-enclosed in ahevacuatedenvelopc. Such Slots or cavities have resonant. frequencies which are dependent upon their dimensions. tron beam 12 which is projected'adjacent thestructure .13

travels through the electromagnetic Wave and interacts therewith. Energy of translation of'the electrons is transfiir r'etl to the wave, and the slots 23 radiate at an angle whichdepend's upon the velocity of the electron stream and the size and spacing of the slots.

' Suitabl'emea'ns are provided for applying voltages to the electrical structure and to the collector. In accord-' aneewith thc invention, a high positive accelerating volt- Ihe conductive The ielecan envelope is schematically s'hown at 48. The beam is maintained parallel and substantially ':planar by suitable electromagnetic or electrostatic focusing. If electrostatic focusing is employed, the outer shell 48 is employed as one of the electrodes and t'he electrical structure 35 as the other electrode between which a suitable electric-field is applied. 7 i I A high accelerating voltage is applied to the electrical structure 35 and to the transparent conductive coating 50 42. Thus there is anacce'lenating field between the elec- "tron guuand surface 51 of the dielectric material which surrounds the electrical structure. The remainderof-the conductive serves to shield the electrical structure iro'r'nstray fields. when the beam"enters -the opening 52 55 it is at its highest velocity and then travels through the i is ted to the electrical structure and as ;a

consequence, th'e front face 26 and the grid '21 have a liigh potential which serves to accelerate the electron stream. The stream then passes through the grid 21 into a 'region which does not have any electric fields and 's'i d'erably lower than the voltage applied to the electrical structure. The electrons emerging irom the opening 18 through the grid '22 are subject to a decelerating field,

the intensity of which is dependent upon the'v oltage applied 'to the collector. The electrons are then decelerated giving up energy to-the means which provides the voltage. Thus it is seen that the hig'h velocity electrons are subjected to a decelerating field which is directly travels :adjacent the elements 23 to the grid 22 where it 6 emerges. The voltage applied to the collector 14 is-con structure and adjacent "the grooves 3'7 to. the exit 53. Someof fthe"energy of translation is transferred to the electromagnetic wave and iamplifiesithe same. Thus the electron s'tream..i's 'slightly'decelerated fin this region.

When 'the e lectron stream emergesat 53:, it still has a Isubsta'ritialamouht tiffkine'tic energy By placing'a low voltage on are collector-35 a decelerating field 'is'produce'd be'tween'the collector 36 fandthe face 5'4 fof'the electrical structure. Tlhus the electrons Tare dec'eflerated and 'give upenergy to the system supplying the fvclt'age. As a consequence, the remaining kinetic energy "is recovered rather than being dissipated 'in the form of heat at the collector 36. The efliciency 6f he vacuum tube is substantially increasead.

It is apparent that electrical structures 'having other configurations may he employed. i Fo'r example, as previouslydescribedihe structure may comprise a series of resonant cavities which are coupled "together by their stray fields. The coupling between: cavities ,may be increased by dorming slots between cavities or by holes to control the size and location of the which couple the cavities together. These slots or holes may also be housed'to control the mode which is propagated by the structure. The grooves may degenerate into mere scratches in which instance a refraction grating is formed. All such configurations of the elements of the electrical structure are understood to be included in the scope of the invention.

In Figure 4 I have shown an electromagnetic wave generator which employs an electrical structure which is cylindrical in form. A hollow electron beam interacts with the electromagnetic wave supported by the structure. The generator shown employs radial electric field focusing of the electron stream.

An annular magentic structure 61 has a coil 62 wound thereon. The structure 61 has a magnetic field gap 63. A radial magnetic field is formed across the gap 63 through which the electrons pass. An annular electron gun designated generally by the reference numeral 64 serves to produce a hollow electron beam. The electron beam is then accelerated and passes through the radial magnetic field where it acquires a rotational velocity. The stream then enters into a radial electric field.

The radial electric field arises from two sources: the charge on the cylindrical electrodes and the space charge. This field balances the centrifugal force of the electrons to maintain the electrons in a cylindrical path as they travel adjacent the electrical structure. Radial field focusing is described in detail in Fundamentals of Electron Motion (McGraw-Hill, 1953) pages 160-163. It is of course to be understood that magnetic field focusing may be employed. The formation of hollow streams in this manner is well known and described in both of the references referred to herein.

The electrical structure 67 is provided with resonant slots 68. These slots may be formed annularly about the structure. For ease of manufacture, these slots may be formed helically as a thread. The electrical structure 67 has an enlarged portion 69 which forms a continuation of the electron gun structure. The collector 71 is disposed to receive the electron stream. Cooling fins 72 are provided for dissipating the heat produced by the electrons striking the collector.

Surrounding the electrical structure there is a transparent dielectric structure 73. The outer surface and ends of the structure are coated with a suitable transparent conductive coating 74 of the type previously described. The hollow electron stream travels adjacent to the electrical structure 68 through the cylindrical opening between the structure and the dielectric material. If desired, grids 75 and 76 may be provided at the ends of the structure to prevent fringing or penetration of electric fields into the opening 77. The electron stream interacts with the electromagnetic wave supported by the structure to amplify the same to produce coherent radiation.

A lens system may be employed to focus the energy which is radiated by the structure. The lens system may comprise any suitable number of lenses and may be adjustable to control the focal distance and size of the image. For example, the lens system may comprise annular lenses 81, 82 and 83. The lens 81 has its surface 84 coated whereby a portion of the radiated energy is reflected to increase the Q of the system. The surface 84 is placed perpendicular to the direction of radiation. The complete structure is enclosed in the metallic envelope 86. The cylindrical electrical structure 67 and the outer envelope 86 are appropriately charged to produce the desired focusing field.

If desired, the electrical structure may be hollow as shown. The vacuum tube may then be sighted through the hollow portion. A suitable eye piece 87 and obiectivtle1 lens system 88 may be provided to form a telescopic sig t.

Although I have described planar and cylindrical structures which serve to support electromagnetic waves, it

6 should be understood thatthe structure may take other forms. The electron stream is then designed to pass adjacent to as much of the surface of the structure as possible for maximum radiation. For example, it may be desirable in certain instances to design a structure having a truncated conical shape.

Again, the accelerating voltage is applied to the electrical structure 67 to accelerate the electrons which enter the cylindrical opening 77. The electrons interact with the electromagnetic wave supported by the electrical structure and then emerge at the end 76. The interacting region is shielded from electric fields by dielectric structure 73, the outer surface of which has a transparent conductive coating 74. A suitable decelerating voltage is applied between the electrical structure and the collector whereby the electrons are decelerated and energy is recovered therefrom.

I claim:

1. A direct radiation vacuum tube comprising: an electron gun for developing a stream of electrons; a collector spaced from said gun and disposed to intercept said electron stream; an electrical structure serving to support an electromagnetic wave disposed between said gun and said collector, said electromagnetic wave interacting with said electron stream whereby the wave is amplified and coherently radiated directly from the interacting region; a member of dielectric material transparent to said electromagnetic wave substantially surrounding said electrical structure and closely circumscribing said electron stream throughout a substantial portion of its path from said electron gun to said collector, said dielectric member being provided with a conductive outer surface transparent to said electromagnetic wave for shielding the interacting region from electric fields; and means for focusing said coherently and directly radiated electromagnetic wave to a distant area external to said tube.

2. A direct radiation vacuum tube as in claim 1 wherein said electrical structure comprises a plurality of coupled resonant cavities.

3. A direct radiation vacuum tube as in claim 1 wherein said electrical structure comprises a plurality of coupled slots. 4

4. A direct radiation vacuum tube as in claim 1 wherein said electrical structure comprises a diffraction gratmg. 7

5. A direct radiation vacuum tube comprising an annular electron gun serving to develop a hollow cylindrical stream of electrons, a collector spaced from said gun and disposed to intercept said stream, a cylindrical electrical structure serving to support electromagnetic waves disposed between said gun and collector, said electron stream serving to interact with said electromagnetic waves to amplify the same and produce electromagnetic energy, coherently radiated directly from the interacting region, a hollow cylindrical dielectric means transparent to said electromagnetic energy surrounding and spaced from said electrical structure, a conductive surface transparent to said electromagnetic energy formed on said dielectric means and serving to shield the interacting region from electric fields, and means for focusing the coherently and directly radiated electromagnetic energy to a distant area external to said tube.

6. A direct radiation vacuum tube as in claim 5 wherein said electrical structure comprises a plurality of coupled resonant cavities.

7. A direct radiation vacuum tube as in claim 5 wherein said electrical structure comprises a plurality of coupled slots.

8. A direct radiation vacuum tube as in claim 5 wherein said electrical structure comprises a difiEraction grating.

9. A direct radiation vacuum tube comprising: an electron gun for developing a stream of electrons; a collector spaced from said gun and disposed to intercept said stream; an electrical structure serving to support an electromagnetic wave disposed between said gun and collector, said electromagnetic wave inter-acting with the electron stream whereby the wave is amplified and coherently radiated direct y qfror-n'the interacting region; a member of dielectricrnater-ialtransparent to said electromagnetic wave substantially surrounding said electrical 7 structure and provided with a conductive outer surface transparent to said electromagnetic wave for shielding the interacting region from electric fields; and a partially reflecting .lens system for focusing the coherently and directly radiated electromagnetic wave and -increasing the Q of the system.

.10, A direct radiation vacuum tube as in :claim 9 .including an input grid disposed between the dielectric meniber and the structure at the gun end of the structure, and an output grid disposed between the dielectric member and the structure and located, at the collector end of the structure, said grids serving to further shield the-interacting region from electric fields. Q llwA direct radiation vacuum tube comprising an annular electron :gun serving to develop a hollow [cylindrical stream of electrons, a collector spaced from said gun and disposed to intercept said stream, a cylindrical elem trical' structure serving to support electromagnetic waves disposed between said gun and collector, said electron stream serving to interact with said electromagnetic waves to amplify the same and produce electromagnetic energy, coherently radiated directly from the interacting region,

a hollow cylindrical dielectric means transparent to electromagnetic energy surrounding and spaced tram said structure, a conductive surface transparent to said electromagnetic energy formed on said dielectric means and serving to shield the interacting reg-ion from electric fields, and a partially reflecting lens :system serving to focusthe coherently and directly radiated electromagnetic energy and increase the Q of the system. 7

References Cited in the file of this patent UNITE-D STATES PATENTS France e. 18,1951

US678606A 1957-08-16 1957-08-16 Direct radiation vacuum tube Expired - Lifetime US2939998A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US678606A US2939998A (en) 1957-08-16 1957-08-16 Direct radiation vacuum tube

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US678606A US2939998A (en) 1957-08-16 1957-08-16 Direct radiation vacuum tube

Publications (1)

Publication Number Publication Date
US2939998A true US2939998A (en) 1960-06-07

Family

ID=24723503

Family Applications (1)

Application Number Title Priority Date Filing Date
US678606A Expired - Lifetime US2939998A (en) 1957-08-16 1957-08-16 Direct radiation vacuum tube

Country Status (1)

Country Link
US (1) US2939998A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3202867A (en) * 1961-05-15 1965-08-24 Gen Electric High frequency energy apparatus with interleaved ladder line slots
US3860880A (en) * 1973-05-18 1975-01-14 California Inst Of Techn Travelling wave optical amplifier and oscillator
US4197483A (en) * 1978-10-18 1980-04-08 The United States Of America As Represented By The Secretary Of The Army Submillimeter wave generation using surface acoustic waves in piezoelectric materials

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2367295A (en) * 1940-05-17 1945-01-16 Bell Telephone Labor Inc Electron discharge device
US2435804A (en) * 1944-01-01 1948-02-10 Rca Corp Cavity resonator magnetron device
FR987573A (en) * 1949-04-05 1951-08-16 Csf constant magnetic field tube for producing waves cention? RIQUES and millimeter
US2611101A (en) * 1947-04-15 1952-09-16 Wallauschek Richard Traeling wave amplifier tube
US2634372A (en) * 1953-04-07 Super high-frequency electromag
US2645737A (en) * 1949-06-30 1953-07-14 Univ Leland Stanford Junior Traveling wave tube
US2654047A (en) * 1948-01-20 1953-09-29 Int Standard Electric Corp Beam traveling wave amplifier tube
US2679019A (en) * 1947-12-02 1954-05-18 Rca Corp High-frequency electron discharge device
US2688107A (en) * 1950-01-25 1954-08-31 Collins Radio Co Electron beam device
US2757311A (en) * 1949-06-02 1956-07-31 Csf Double beam progressive wave tube
US2804511A (en) * 1953-12-07 1957-08-27 Bell Telephone Labor Inc Traveling wave tube amplifier
US2812467A (en) * 1952-10-10 1957-11-05 Bell Telephone Labor Inc Electron beam system
US2851631A (en) * 1955-03-07 1958-09-09 Hughes Aircraft Co Traveling wave tube of high forward wave impedance

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2634372A (en) * 1953-04-07 Super high-frequency electromag
US2367295A (en) * 1940-05-17 1945-01-16 Bell Telephone Labor Inc Electron discharge device
US2435804A (en) * 1944-01-01 1948-02-10 Rca Corp Cavity resonator magnetron device
US2611101A (en) * 1947-04-15 1952-09-16 Wallauschek Richard Traeling wave amplifier tube
US2679019A (en) * 1947-12-02 1954-05-18 Rca Corp High-frequency electron discharge device
US2654047A (en) * 1948-01-20 1953-09-29 Int Standard Electric Corp Beam traveling wave amplifier tube
FR987573A (en) * 1949-04-05 1951-08-16 Csf constant magnetic field tube for producing waves cention? RIQUES and millimeter
US2757311A (en) * 1949-06-02 1956-07-31 Csf Double beam progressive wave tube
US2645737A (en) * 1949-06-30 1953-07-14 Univ Leland Stanford Junior Traveling wave tube
US2688107A (en) * 1950-01-25 1954-08-31 Collins Radio Co Electron beam device
US2812467A (en) * 1952-10-10 1957-11-05 Bell Telephone Labor Inc Electron beam system
US2804511A (en) * 1953-12-07 1957-08-27 Bell Telephone Labor Inc Traveling wave tube amplifier
US2851631A (en) * 1955-03-07 1958-09-09 Hughes Aircraft Co Traveling wave tube of high forward wave impedance

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3202867A (en) * 1961-05-15 1965-08-24 Gen Electric High frequency energy apparatus with interleaved ladder line slots
US3860880A (en) * 1973-05-18 1975-01-14 California Inst Of Techn Travelling wave optical amplifier and oscillator
US4197483A (en) * 1978-10-18 1980-04-08 The United States Of America As Represented By The Secretary Of The Army Submillimeter wave generation using surface acoustic waves in piezoelectric materials

Similar Documents

Publication Publication Date Title
US3129356A (en) Fast electromagnetic wave and undulating electron beam interaction structure
Flyagin et al. The gyrotron
US4002912A (en) Electrostatic lens to focus an ion beam to uniform density
Lovelace Dynamo model of double radio sources
Granatstein et al. A quarter century of gyrotron research and development
US4504964A (en) Laser beam plasma pinch X-ray system
Cohen Radiation in a plasma. I. Čerenkov effect
US2220839A (en) Electrical discharge device
Krushelnick et al. Ultrahigh-intensity laser-produced plasmas as a compact heavy ion injection source
US3989994A (en) Space oriented microwave power transmission system
US2653270A (en) High-frequency energy interchange device
US2599864A (en) Wave front modifying wave guide system
US2741718A (en) High frequency apparatus
US3755815A (en) Phased array fed lens antenna
US5780970A (en) Multi-stage depressed collector for small orbit gyrotrons
Ginzburg Reviews of Topical Problems: Certain Theoretical Aspects of Radiation due to Superluminal Motion in a Medium
US3648056A (en) Optical detector with radiant energy absorbing chamber
US6993115B2 (en) Forward X-ray generation
US4727550A (en) Radiation source
Piosczyk et al. Coaxial cavity gyrotron-recent experimental results
US4395631A (en) High density ion source
RU2195742C2 (en) Thermionic electric converter
US4453108A (en) Device for generating RF energy from electromagnetic radiation of another form such as light
US2634372A (en) Super high-frequency electromag
US3778612A (en) Neutral particle beam separator and velocity analyzer using radiation pressure