GB1290240A - - Google Patents

Info

Publication number
GB1290240A
GB1290240A GB1290240DA GB1290240A GB 1290240 A GB1290240 A GB 1290240A GB 1290240D A GB1290240D A GB 1290240DA GB 1290240 A GB1290240 A GB 1290240A
Authority
GB
United Kingdom
Prior art keywords
magnetic
unit
polepieces
compensator
flux
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
Application number
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 filed Critical
Publication of GB1290240A publication Critical patent/GB1290240A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
    • H01J37/10—Lenses
    • H01J37/14—Lenses magnetic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
    • H01J37/10—Lenses
    • H01J37/14—Lenses magnetic
    • H01J37/141—Electromagnetic lenses

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Electron Sources, Ion Sources (AREA)
  • Electron Beam Exposure (AREA)

Abstract

1290240 Electron beam electromagnetic focusing apparatus HITACHI Ltd 10 June 1970 [13 June 1969] 28237/70 Heading H1D A magnetic electron lens suitable for an electron microscope comprising polepieces 4 and 5 within an exciting coil 1<SP>1</SP> enclosed within a peripheral iron cover 1 and upper and lower magnetic path units 2 and 3 respectively has an adjustable magnetic piece 8, e.g. ferromagnetic in contact with the lower magnetic path unit 3 to centre the beam by compensating for effects of magnetic flux leakage. The polepieces are separated by a non-magnetic spacer 5<SP>1</SP> and the annular compensating piece 8 provides a path parallel to the magnetic path unit 3 for the magnetic flux B. Various alternative embodiments are given. In Fig. 3 (not shown) air gap (9) in unit 3 ensures most flux passes through compensator (10); in Fig. 4 (not shown), compensator (11) has a structure extending below as well as above unit 3 to prevent outward flow of flux in the air gap; and in Fig. 5 (not shown) the coil bobbin has an inner wall of non-magnetic material A 3 adjacent the polepieces and upper and lower portions of ferromagnetic material A 1 , A 2 , where the lower portion is adjustable by screws 7. Fig. 6 (not shown) discloses a further construction wherein a portion only of the lower surface of compensator (12) contacts unit 3.
GB1290240D 1969-06-13 1970-06-10 Expired GB1290240A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5507769 1969-06-13

Publications (1)

Publication Number Publication Date
GB1290240A true GB1290240A (en) 1972-09-20

Family

ID=12988624

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1290240D Expired GB1290240A (en) 1969-06-13 1970-06-10

Country Status (3)

Country Link
US (1) US3643191A (en)
GB (1) GB1290240A (en)
NL (1) NL147280B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4178094A (en) * 1978-09-01 1979-12-11 Xerox Corporation Belt support and steering module
FR2491258A1 (en) * 1980-09-29 1982-04-02 Le N Proizv Opto-electronic system for electron microscope - has lenses formed around single magnetic core with annular grooves
US4698611A (en) * 1986-12-03 1987-10-06 General Electric Company Passive shimming assembly for MR magnet

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB680300A (en) * 1950-02-23 1952-10-01 Vickers Electrical Co Ltd Improvements relating to magnetic electron lenses
US2637000A (en) * 1951-02-15 1953-04-28 Magnetic electron -lens

Also Published As

Publication number Publication date
NL147280B (en) 1975-09-15
NL7008534A (en) 1970-12-15
US3643191A (en) 1972-02-15

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PLNP Patent lapsed through nonpayment of renewal fees