[go: up one dir, main page]

GB2217104A - Electron gun assembly, especially for an electron microscope - Google Patents

Electron gun assembly, especially for an electron microscope Download PDF

Info

Publication number
GB2217104A
GB2217104A GB8907103A GB8907103A GB2217104A GB 2217104 A GB2217104 A GB 2217104A GB 8907103 A GB8907103 A GB 8907103A GB 8907103 A GB8907103 A GB 8907103A GB 2217104 A GB2217104 A GB 2217104A
Authority
GB
United Kingdom
Prior art keywords
electron
bushing
electron gun
gun assembly
anode body
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.)
Withdrawn
Application number
GB8907103A
Other versions
GB8907103D0 (en
Inventor
Emil Vratnicek
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.)
Tesla Koncernovy Podnik
Original Assignee
Tesla Koncernovy Podnik
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 Tesla Koncernovy Podnik filed Critical Tesla Koncernovy Podnik
Publication of GB8907103D0 publication Critical patent/GB8907103D0/en
Publication of GB2217104A publication Critical patent/GB2217104A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02Details
    • H01J37/04Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement or ion-optical arrangement
    • H01J37/06Electron sources; Electron guns
    • H01J37/067Replacing parts of guns; Mutual adjustment of electrodes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Electron Sources, Ion Sources (AREA)

Description

1 C 1 1 2.2117104 E1ECTRON GUN ASSEMBILY The invention relates to an
electron gun assembly, especially for an electron microscope, which comprises a cathode, arranged in a Wehnelt 3610 1 cylinder, and an anode, which is arranged opposite to the cathode and which is provided with a central hole.
Electron guns-of electron microscopes are currently constructed with high tension vacuum bushing in the form of a tube of electroinsulating material, which is with one of its ends connected to Uhe casing of an electron microscope column, while its other end is connected to the electron gun. Another known construction of an electron gun is provided with a high tension vacuum bushing in the form of a plate of an eleclilroinsu--,R"UL-.F, material, which is fastened with its periphery to the electron microscope column casing, while in the central part of said plate is arranged a vacuumtight electrical bushing, to which the elect-l- on gun is fastened.
The drawbacks of these known constructions 0 said reside especially in the big dimensions of k -ron g-an using a tube electron guns. Such an elect! high tension electron blushing is too long, whIle an t electron gun using a plate-shaped hig,-- Uension electron bushing is too wide. F.a.--the-^:,more these solutions necessitate, for protection against radiation, the use of a bulky anode cover, which.
d electron gun. further increases the weight of sai This is again a big disadvantage es-Qec--all,-, -'or portable electron microscopes.
According to the invention the above "i cal mentioned drawbacks of prior art are pract j i ally for removed by an elect-ron gun assembly, especi an electron microscope, which comprises a cathode, arranged in a Wehnelt cylinder, and an a-lode, c 3610 -2which is arranged opposite said cathode and which is provided with a central hole, wherein the Wehnelt cylinder is fastened to the top part of a high tension vacuum bushing, formed in the shape of a bell, which is with its.open end slidably placed on an anode body, and between said anode body and said high tension vacuum bushing is in a groove arranged a vacuum seal. In one preferred embodiment of the invention said groove is made in said anode body, while in another embodiment of said invention said groove is made in a contact surface of said high tension vacuum bushing. There is fuze-ther another embodiment of the invention, where in an elevated collar of said anode body is made a set of internally - threaded holes, arranged radially with regular angular spacings; in the holes are screwed ad-us-,.inz 4 screws, the operating heads of whLch are situated outside a microscope column and the shan]:s of which contact the outer surface of the bushing.
The advantages of the electron gun assembly according to the invention consist especially in the compactness and small weight o-L Uhe electron gun, which enables the electron gun to be used especially -0 for a portable electron microscope. Ano-thel, advantage consists in the simplification of the anode casing and in avoidance of a big diametet, seal.
The invention will now be described, by way of example, with reference to the accompanying diagrammatic drawing, which schematically J-11-lustrates, in a partial section, a preferred I embodiment of an electron gun assembly accor-di-6 Lo Uhe invention.
The drawing shows a high tension vacuum -op bushing 1 in the shape of a bell provided in its t - " e ir narrow part with an axial hole 1A. in, the hol n 1 J 1 1 3 3610 -3the bushing 1 is vacuumtighly fastened a Wehnelt cylinder 2 in which is arranged a cathode. The vacuumtight sealing of the Wehnelt cylinder 2 is obtained with the help of O-rings 3. The bushing 1 is with its seating face, formed at its open end, slidably situated on a vacuum seal 4, embedded in a groove 5 in an anode body 6. The anode body 6 is provided with a central hole 6A, anode 6Band an elevated collar 7, in which are made several (preferably three or four) radial, internally threaded holes 8 arranged with uniform angular spacing. In the holes 8 are screwed adjusting screws 9, the operating heads of which are situated J-side the anode body 6 and the shanks of which ou U contact the outer surface of the bushing 1. On the collar 7 is situated an anode casing 11. A high tension cable 12 is elect--ically connected to the Wehnelt cylinder 2. Vacuum is produced inside the bushing 1 by a pumping system communicating with the inner space of the bushing 1 via the hole 6A.
In operation of the electron gun assembly according to the invention high tension is supplied to the Weh,elt cylinder 2 through the high tension cable 12 and the cathode in the cylinder 2 produces an electron beam which passes through the central hole 6A. The high tension is insulated from the anode body 6 by the vacuum inside the bushing 1, by the soace outside of the bushing 1 and by the A ' bushing 1. 'The position of the bushing 1, and consequently the position of the cathode in the 1 ' cylinder 2, and therefore o. Whe electron beam with respect to the central hole 6A, is adjusted by the n the vaculam screws 9, which move the bushi.'1g 1 o, seal 4 with respect to the centr- R'L hole 6A in the anode body 6.
1 C 3610 The invention can preferably be used when constructing a portable electron microscope.
i 1 C_ 3610

Claims (5)

1. Electron gun assembly, especially-for an electron microscope, the assembly comprising a cathode, arranged in a Wehnelt cylinder, and an anode, which is arranged opposite to said cathode and which is provided with a central hole, wherein the Wehnelt cylinder is fastened inside the top part of a high tension vacuum bushing, formed in the shape of a bell, which is with its open end slidably placed on an anode body, and between said anode body and said high tension vacuum bushing is situated a vacuum seal arranged in a groove.
2. Electron gun assembly according to Claim 1, 4 L where n the groove is made in the anode body.
3. Electron gan assembly according to Ulaim 1 wherein the groove is made in a contact surface o.
the high tension vacuum bushing.
4. Electron gun assembly according to any one of Claims 1 to 3, wherein the anode body has an elevated collar in which is made a set of internally threaded holes, arranged radially with regular spacings, in the-holes are screwed adjusting screws the operating heads of which are situated outside of a microscope column and the shanks of which contact the outer surface of the bushing.
5. Electron gun assembly according to Claim 1 constructed, arranged and adapted to operate substantially as herein described with reference to, and as shown in, the accompanying drawing.
Published 1989 at The Patent Office. State House, 6671 High Holborn, London WC1 R 4TP. Further copies mkv be obtained from The Patent Ofnce.
GB8907103A 1988-04-08 1989-03-29 Electron gun assembly, especially for an electron microscope Withdrawn GB2217104A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CS882400A CS268377B1 (en) 1988-04-08 1988-04-08 Electron gun for electron microscope

Publications (2)

Publication Number Publication Date
GB8907103D0 GB8907103D0 (en) 1989-05-10
GB2217104A true GB2217104A (en) 1989-10-18

Family

ID=5361045

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8907103A Withdrawn GB2217104A (en) 1988-04-08 1989-03-29 Electron gun assembly, especially for an electron microscope

Country Status (5)

Country Link
JP (1) JPH01298631A (en)
CN (1) CN1037615A (en)
CS (1) CS268377B1 (en)
DE (1) DE3911446A1 (en)
GB (1) GB2217104A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB736216A (en) * 1951-01-31 1955-09-07 Sueddeutsche Laboratorien Gmbh Improvements in electronic gun devices, particularly for heating objects
US3636346A (en) * 1968-03-17 1972-01-18 Hitachi Ltd Electron beam generator for electron microscope or the like apparatus
GB1409309A (en) * 1971-12-29 1975-10-08 Aquitaine Petrole Glow-tube suitable for use in x-ray spectrometry
US4020353A (en) * 1974-09-06 1977-04-26 Hitachi, Ltd. Sample analysis apparatus using electron beam irradiation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB736216A (en) * 1951-01-31 1955-09-07 Sueddeutsche Laboratorien Gmbh Improvements in electronic gun devices, particularly for heating objects
US3636346A (en) * 1968-03-17 1972-01-18 Hitachi Ltd Electron beam generator for electron microscope or the like apparatus
GB1409309A (en) * 1971-12-29 1975-10-08 Aquitaine Petrole Glow-tube suitable for use in x-ray spectrometry
US4020353A (en) * 1974-09-06 1977-04-26 Hitachi, Ltd. Sample analysis apparatus using electron beam irradiation

Also Published As

Publication number Publication date
JPH01298631A (en) 1989-12-01
DE3911446A1 (en) 1989-10-19
GB8907103D0 (en) 1989-05-10
CN1037615A (en) 1989-11-29
CS268377B1 (en) 1990-03-14
CS240088A1 (en) 1989-08-14

Similar Documents

Publication Publication Date Title
US6586729B2 (en) Ion mobility spectrometer with non-radioactive ion source
DE59302504D1 (en) Plasma spray gun
US3809899A (en) Electron-beam tube including a thermionic-field emission cathode for a scanning electron microscope
US4017757A (en) Multi-target X-ray tube
US4900982A (en) Electron gun design
GB2217104A (en) Electron gun assembly, especially for an electron microscope
Hogg Conversion of mass spectrometers for fast-atom bombardment using easily constructed components
US3794872A (en) Moving target spring loaded x-ray tube
KR930017078A (en) Mechanically Stable Radiant Gun Assembly
US5623183A (en) Diverging beam electron gun for a toxic remediation device with a dome-shaped focusing electrode
EP0167347A3 (en) Gas laser tube apparatus
US5200578A (en) High voltage feedthrough bushing
US3187220A (en) Hydraulically tuned magnetron
US6683317B1 (en) Electrically insulating vacuum coupling
KR102452041B1 (en) High voltage feedthrough assembly for high vacuum environments of gas cluster ion beam system
US4622453A (en) Electron beam gun mounting on a work chamber
US2420207A (en) Electron gun mounting
US5763889A (en) Electron beam-generating apparatus
US2906903A (en) Low voltage 14 mev. neutron source
JPH0328014B2 (en)
US3469093A (en) Mass spectrometer ion source with dual interlocked valve means for evacuation purposes
KR840001382A (en) Cathode ray tube
US4879490A (en) Gas discharge devices wherein electrons are injected into a high field region
JPH05275035A (en) X-ray tube
JPS57834A (en) Image pick-up tube

Legal Events

Date Code Title Description
WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)