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 |
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