GB711672A - Improvements in or relating to electron microscopes - Google Patents
Improvements in or relating to electron microscopesInfo
- Publication number
- GB711672A GB711672A GB14840/52A GB1484052A GB711672A GB 711672 A GB711672 A GB 711672A GB 14840/52 A GB14840/52 A GB 14840/52A GB 1484052 A GB1484052 A GB 1484052A GB 711672 A GB711672 A GB 711672A
- Authority
- GB
- United Kingdom
- Prior art keywords
- pole
- focus
- lens
- june
- spacing
- 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
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
- H01J37/141—Electromagnetic lenses
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Electron Sources, Ion Sources (AREA)
Abstract
711,672. Electron microscopes. PHILIPS ELECTRICAL INDUSTRIES, Ltd. June 12, 1952 [June 15, 1951], No. 14840/52. Drawings to Specification. Class 39(1) An electron microscope embodies a lens wherein the magnetomotive force is such that the lower limit of magnetic saturation is reached in the polepieces, the diameter of the bores in the pole-pieces being not more than one-third of the distance between the pole-faces, and the space between the pole-faces being long enough for a focus to be located therein but as short as is compatible with the insertion of an object between the focus and that pole-face which is first traversed by the electrons. It is explained in the Specification that with this spacing, the use of a narrow bore in the pole shoes results in a more powerful lens for a given number of ampere turns but does not increase the astigmatism; the power supplies require less stringent stabilization, and for a resolving power of 60.U. the operating voltage may vary by ¢ to 1 per cent and the energizing current by -¢ per cent. In a microscope operating at 80 Kv the spacing between the pole shoes may be 1.4 mm. and the bore 0.3 mm.; this gives a focal length of 0.7 mm. and a magnification of 140; the lens requires about 3000 ampere turns and the first focus is 0.3 mm. from the pole-face.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL302722X | 1951-06-15 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB711672A true GB711672A (en) | 1954-07-07 |
Family
ID=19783367
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB14840/52A Expired GB711672A (en) | 1951-06-15 | 1952-06-12 | Improvements in or relating to electron microscopes |
Country Status (6)
Country | Link |
---|---|
US (1) | US2670450A (en) |
BE (1) | BE512056A (en) |
CH (1) | CH302722A (en) |
DE (1) | DE918464C (en) |
FR (1) | FR1071047A (en) |
GB (1) | GB711672A (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL103598C (en) * | 1957-03-13 | |||
DE1614407B1 (en) * | 1967-01-13 | 1972-08-03 | Siemens Ag | ARRANGEMENT FOR GENERATING A BODY RAY IN A BODY DEVICE, IN PARTICULAR ELECTRON MICROSCOPE, ELECTROMAGNETIC FIELD INFLUENCING |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2418349A (en) * | 1945-12-13 | 1947-04-01 | Rca Corp | Method of and means for correcting for distortion in electron lens systems |
US2438971A (en) * | 1946-10-31 | 1948-04-06 | Rca Corp | Compound electron objective lens |
US2472315A (en) * | 1948-03-30 | 1949-06-07 | Rca Corp | Varying the gap spacing of pole pieces for electron optical apparatus |
-
0
- BE BE512056D patent/BE512056A/xx unknown
-
1952
- 1952-05-23 US US289685A patent/US2670450A/en not_active Expired - Lifetime
- 1952-06-11 DE DEN5633A patent/DE918464C/en not_active Expired
- 1952-06-12 GB GB14840/52A patent/GB711672A/en not_active Expired
- 1952-06-13 FR FR1071047D patent/FR1071047A/en not_active Expired
- 1952-06-13 CH CH302722D patent/CH302722A/en unknown
Also Published As
Publication number | Publication date |
---|---|
FR1071047A (en) | 1954-08-24 |
CH302722A (en) | 1954-10-31 |
US2670450A (en) | 1954-02-23 |
BE512056A (en) | |
DE918464C (en) | 1954-09-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2305761A (en) | Electron-optical lens | |
US3237059A (en) | Permanent magnet system for producing a magnetic field for the focused passage of a beam of electrons | |
US2433682A (en) | Electron focusing apparatus | |
US2149101A (en) | Cathode ray tube | |
GB480948A (en) | Improvements in or relating to cathode ray tubes | |
GB644327A (en) | Projection cathode ray tubes | |
US3315125A (en) | High-power ion and electron sources in cascade arrangement | |
GB1594465A (en) | Electron beam apparatus | |
US3238414A (en) | High output duoplasmatron-type ion source | |
GB711672A (en) | Improvements in or relating to electron microscopes | |
GB828224A (en) | High-compression beam generating system for velocity-modulated tubes | |
GB665094A (en) | Improvements relating to the reduction of primary spherical aberration in magnetic electron lenses | |
US2718606A (en) | Combination electromagnet-permanent magnet focusing devices | |
US3150258A (en) | Electromagnetic stigmators for correcting electron-optical deficiencies in the lenses of electron beam instruments | |
US4468563A (en) | Electron lens | |
US2405477A (en) | Ray-generating apparatus | |
US3890533A (en) | Thermal emission type electron gun | |
US2185857A (en) | Electro-optical image device | |
WO2014030429A1 (en) | Charged particle beam device and objective lens | |
Hordon et al. | Limits of low‐energy electron optics | |
US10297413B2 (en) | Method and device for the production of highly charged ions | |
GB860557A (en) | Improvements in or relating to electron beam discharge apparatus | |
US2632115A (en) | Focusing device for electron microscopes | |
US3731094A (en) | Electron beam apparatus with means for generating a rotation-symmetrical magnetic field | |
SU1275585A1 (en) | Sonde-forming system for scanning electron microscope |