US2265746A - Secondary emission multiplier - Google Patents
Secondary emission multiplier Download PDFInfo
- Publication number
- US2265746A US2265746A US354739A US35473940A US2265746A US 2265746 A US2265746 A US 2265746A US 354739 A US354739 A US 354739A US 35473940 A US35473940 A US 35473940A US 2265746 A US2265746 A US 2265746A
- Authority
- US
- United States
- Prior art keywords
- electrodes
- electrons
- multiplier
- secondary emission
- electrode
- 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
Links
- 230000001133 acceleration Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 206010037660 Pyrexia Diseases 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
- H01J43/04—Electron multipliers
- H01J43/06—Electrode arrangements
- H01J43/18—Electrode arrangements using essentially more than one dynode
- H01J43/22—Dynodes consisting of electron-permeable material, e.g. foil, grid, tube, venetian blind
Definitions
- This invention relates to secondary emission multipliers and in particular to the type of multiplier in which a number of secondary emission electrodes in the form of grids or nets are arranged transversely to the main path of the electrons.
- the plane of the grids in such multipliers is usually substantially perpendicular to the main discharge path.
- a further object is to improve the form of multipliers in which the grid electrodes have increasing surfaces in progressive stages so that a larger surface is present for taking up the larger current.
- the concentric arrangements which have been suggested for this purpose are very difficult to construct because, the practice with contrary to ordinary amplifier tubes, grids of a very close mesh must be used.
- At least a part of the secondary emissive electrodes is curved concavely towards the cathode, the radius of curvature of the electrodes being substantially equal for all the curved electrodes.
- the centres of the curved electrodes are not coincident but are shifted from stage to stage in the direction of the electron current.
- This arrangement has the effect that the electron current is distributed from stage to stage over a wider surface because the strength of the electric field increases from the axis of the arrangement in the direction towards the edge.
- This electrode arrangement fits easily into a cylindrical bulb having a spherical end portion.
- the tube of the invention must be distinguished from multipliers having grid electrodes curved convexly towards the cathode in order to produce a concentrating effect upon the electrons.
- the envelope 1 consisting, for example, of glass carries on a presser foot a cathode 2, a control grid 3 and an accelerating electrode 4. This system is used for producing the primary electrons.
- a shield electrode 5 surrounds this electrode arrangement and deflects the primary electrons in the direction of the axis of the tube towards the first secondary emissive grid 6.
- the multiplying arrangement consists of a number of spherically curved grids 6 the centres of curvature of which however do not coincide. The radius of curvature is the same for all the grids. The centres of curvature are shifted in the direction of the electron current and of increasing potentials of the electrodes.
- the multiplier system is limited by a conical surface within which the electrodes 5 are impacted by electrons approximately uniformly over their entire surfaces.
- the lines 1 represent the path of electrons emitted near the edge of the first grid. These paths show that the electrons are drawn outwardly from stage to stage so that the total surface of the electrodes impacted by the electrons is increased from stage to stage.
- the last secondary emissive electrode is a metallic layer 8 upon the wall of the tube I, while the output electrode 9 has the form of a grid of wide mesh, situated between the electrode 8 and the last electrode 6. This arrangement has the advantage that the electrode 8 can be easily and intensively cooled from the outside of the tube.
- the arrangement can be modified by inserting between the system for producing the primary electrons and the electrodes 6 one or a number of plane secondary emissive electrodes.
- the arrangement can further be modified by using cylindrically curved electrodes instead of the spherically curved electrodes.
- the grids can also be replaced by foils adapted to emit electrons from the side directed away from the impacted side.
- the spherically curved electrodes are preferably made all with one and the same forming tool because they have all the same radius of curvature.
- Th invention is not limited to the special construction shown in the figure. It can be used in connection with a photoelectric cathode or with input and control systems of different design.
- Secondary emission multiplier including a cylindrical acceleration grid mountedwith the axis of the cylindrical grids in alinement with the main dscharge path of said secondary emissive electrodes.
- Secondary emission multipler including" in an evacuated envelope a sourcei bf lelectronsaa plurality of foraminous s'econdary emissive electrodes mounted one behind the other transversely to the main discharge,,-path,-?said:::electrodes having a concave curvatureiatowards-isaid source of electrons, said source of electrons including a cathode, a cylindrical controlgridand' a cylindrical acceleration grid mounted with the axis of the cylindrical grids in alinement with the main discharge path of said secondary emissive electrodes. and a negative shield elec- 5 trode surrounding said source of electrons and having an opening in the direction of said secondary emissive electrodes.
- Secondary emission multiplier including in an evacuated envelope a plurality of foraminous 'secondary emissive electrodes mounted one be- .hi-nd-rt-he-,othertransversely to the main discharge path, said electrodes having a concave curvature towards the source of electrons, the radius-jotcurvature being substantially the same 15 for allsa'id "electrodes, and a secondary emissive eelectrode in the-form of a wall coating covering the part -of 'said envelope situated in the direction of the main discharge path.
Landscapes
- Electron Sources, Ion Sources (AREA)
Description
9, M. QANEHAGEN Filed Aug. 29. 1940 Patented Dec. 9, 1941 SECONDARY EMISSION MULTIPLIER Max Sandhagen, Berlin-Zehlendorf, Germany,
assignor to Fernseh G. in. b. H., Berlin-Zehlendorf, Germany Application August 29, 1940, Serial No. 354,739 4 InGermany September 19, 1939 8 Claims.
This invention relates to secondary emission multipliers and in particular to the type of multiplier in which a number of secondary emission electrodes in the form of grids or nets are arranged transversely to the main path of the electrons. The plane of the grids in such multipliers is usually substantially perpendicular to the main discharge path.
It is an object of the invention to provide a multiplier having a high output current. It is a further object to overcome the difliculties which are produced by high current densities in the last multiplier stages resulting in high temperatures of the output electrodes. These high tempera tures must be avoided because the emitting layers of the secondary emissive electrodes are very sensitive to high temperatures and lose their emissive properties. It is a further object to provide a multiplier having a linear amplification which is not changed by space charges between the electrodes.
A further object is to improve the form of multipliers in which the grid electrodes have increasing surfaces in progressive stages so that a larger surface is present for taking up the larger current. The concentric arrangements which have been suggested for this purpose are very difficult to construct because, the practice with contrary to ordinary amplifier tubes, grids of a very close mesh must be used.
According to the invention at least a part of the secondary emissive electrodes is curved concavely towards the cathode, the radius of curvature of the electrodes being substantially equal for all the curved electrodes. The centres of the curved electrodes are not coincident but are shifted from stage to stage in the direction of the electron current. This arrangement has the effect that the electron current is distributed from stage to stage over a wider surface because the strength of the electric field increases from the axis of the arrangement in the direction towards the edge. This electrode arrangement fits easily into a cylindrical bulb having a spherical end portion. The tube of the invention must be distinguished from multipliers having grid electrodes curved convexly towards the cathode in order to produce a concentrating effect upon the electrons.
Other aspects of my invention will be apparent or will be specifically pointed out in the description forming a part of this specification, but I do not limit myself to the embodiment of the invention herein described, as various forms may be adopted within the scope of the claims.
Referring to the drawing the single figure shows a longitudinal cross-section through a multiplier according to the invention.
The envelope 1 consisting, for example, of glass carries on a presser foot a cathode 2, a control grid 3 and an accelerating electrode 4. This system is used for producing the primary electrons. A shield electrode 5 surrounds this electrode arrangement and deflects the primary electrons in the direction of the axis of the tube towards the first secondary emissive grid 6. The multiplying arrangement consists of a number of spherically curved grids 6 the centres of curvature of which however do not coincide. The radius of curvature is the same for all the grids. The centres of curvature are shifted in the direction of the electron current and of increasing potentials of the electrodes. The multiplier system is limited by a conical surface within which the electrodes 5 are impacted by electrons approximately uniformly over their entire surfaces. The lines 1 represent the path of electrons emitted near the edge of the first grid. These paths show that the electrons are drawn outwardly from stage to stage so that the total surface of the electrodes impacted by the electrons is increased from stage to stage. The last secondary emissive electrode is a metallic layer 8 upon the wall of the tube I, while the output electrode 9 has the form of a grid of wide mesh, situated between the electrode 8 and the last electrode 6. This arrangement has the advantage that the electrode 8 can be easily and intensively cooled from the outside of the tube.
The arrangement can be modified by inserting between the system for producing the primary electrons and the electrodes 6 one or a number of plane secondary emissive electrodes. The arrangement can further be modified by using cylindrically curved electrodes instead of the spherically curved electrodes. The grids can also be replaced by foils adapted to emit electrons from the side directed away from the impacted side.
The spherically curved electrodes are preferably made all with one and the same forming tool because they have all the same radius of curvature.
Th invention is not limited to the special construction shown in the figure. It can be used in connection with a photoelectric cathode or with input and control systems of different design.
What I claim is:
1. Secondary emission multiplier including a cylindrical acceleration grid mountedwith the axis of the cylindrical grids in alinement with the main dscharge path of said secondary emissive electrodes.
2. Secondary emission multipler including" in an evacuated envelope a sourcei bf lelectronsaa plurality of foraminous s'econdary emissive electrodes mounted one behind the other transversely to the main discharge,,-path,-?said:::electrodes having a concave curvatureiatowards-isaid source of electrons, said source of electrons including a cathode, a cylindrical controlgridand' a cylindrical acceleration grid mounted with the axis of the cylindrical grids in alinement with the main discharge path of said secondary emissive electrodes. and a negative shield elec- 5 trode surrounding said source of electrons and having an opening in the direction of said secondary emissive electrodes. I
t 3: Secondary emission multiplier including in an evacuated envelope a plurality of foraminous 'secondary emissive electrodes mounted one be- .hi-nd-rt-he-,othertransversely to the main discharge path, said electrodes having a concave curvature towards the source of electrons, the radius-jotcurvature being substantially the same 15 for allsa'id "electrodes, and a secondary emissive eelectrode in the-form of a wall coating covering the part -of 'said envelope situated in the direction of the main discharge path.
MAX SANDI-IAGEN.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2265746X | 1939-09-19 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2265746A true US2265746A (en) | 1941-12-09 |
Family
ID=7992989
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US354739A Expired - Lifetime US2265746A (en) | 1939-09-19 | 1940-08-29 | Secondary emission multiplier |
Country Status (2)
Country | Link |
---|---|
US (1) | US2265746A (en) |
FR (1) | FR872458A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2758790A (en) * | 1951-04-02 | 1956-08-14 | Hanson Gorrill Brian Inc | Electronic counting tube and circuit |
US2916662A (en) * | 1952-04-05 | 1959-12-08 | Philips Corp | Memory tube |
-
1940
- 1940-08-29 US US354739A patent/US2265746A/en not_active Expired - Lifetime
-
1941
- 1941-05-24 FR FR872458D patent/FR872458A/en not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2758790A (en) * | 1951-04-02 | 1956-08-14 | Hanson Gorrill Brian Inc | Electronic counting tube and circuit |
US2916662A (en) * | 1952-04-05 | 1959-12-08 | Philips Corp | Memory tube |
Also Published As
Publication number | Publication date |
---|---|
FR872458A (en) | 1942-06-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB634639A (en) | Improvements in or relating to television tubes incorporating electron multiplier units | |
US2138928A (en) | Electron discharge device | |
US3260876A (en) | Image intensifier secondary emissive matrix internally coated to form a converging lens | |
US2547200A (en) | Getter structure for electric discharge tubes | |
US2164892A (en) | Secondary emission tube | |
US2452044A (en) | High emission cathode | |
US2265746A (en) | Secondary emission multiplier | |
US2147756A (en) | Secondary electron tube | |
US2176221A (en) | Electron discharge apparatus | |
US2841728A (en) | Electron multipliers | |
RU2581833C1 (en) | Source of electrons with auto electronic emitter and x-ray tube with said electron source | |
US2254128A (en) | Electron multiplier | |
US2868994A (en) | Electron multiplier | |
GB721571A (en) | Cathode ray tube utilizing a plurality of electron beams | |
US2130281A (en) | Electron discharge tube | |
US2243178A (en) | Electron multiplier | |
US3491233A (en) | Image intensifier devices | |
US2340631A (en) | Secondary electron amplifier | |
NO164687B (en) | DEVICE FOR SHADOW GRIDS FOR ELECTRON CANNON OF THE DUAL MODE TYPE. | |
US1659636A (en) | Device fob amplifying voltage and cubeent | |
US2225786A (en) | Secondary emitting tube | |
US2227095A (en) | Discharge tube | |
GB730862A (en) | Improvements in or relating to vacuum discharge tubes | |
US2151783A (en) | Secondary electron discharge tube | |
US2246172A (en) | Electron multiplier tube |