GB744647A - Improvements in or relating to magnetic electron lenses and pole pieces for use therein - Google Patents
Improvements in or relating to magnetic electron lenses and pole pieces for use thereinInfo
- Publication number
- GB744647A GB744647A GB24508/53A GB2450853A GB744647A GB 744647 A GB744647 A GB 744647A GB 24508/53 A GB24508/53 A GB 24508/53A GB 2450853 A GB2450853 A GB 2450853A GB 744647 A GB744647 A GB 744647A
- Authority
- GB
- United Kingdom
- Prior art keywords
- pole
- copper
- electron lenses
- bore
- pieces
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Electron Beam Exposure (AREA)
Abstract
744,647. Electron lenses. PHILIPS ELECTRICAL INDUSTRIES, Ltd. Sept. 4, 1953 [Sept. 9, 1952], No. 24508/53. Class 39 (1). In magnetic electron lenses for electron microscopes, of the kind in which the beam passes through bores 3, 4, Fig. 1, in two polepieces 1, 2 opposing each other to form a gap, the material in.the region adjacent the bore and the gap is arranged to have a greater incremental permeance in the axial direction than in any direction perpendicular to the axis; this gives a field curve with steeper flanks and thus a greater lens strength for the same magnetomotive force. The result may be achieved by cutting a slot 8; or by mounting separate cylinder 14, Fig. 3, within a widened bore by means of copper or aluminium 16; or by winding copper and iron strips in a double layer helically within a widened bore, Fig. 4 (not shown); or by making the whole pole-piece, or the helical strip of Fig. 4 (without the copper spacer), of magnetically anisotropic material. Both pole-pieces may be so treated, or only the one on the object side. The pole-pieces may be energized by coils or by permanent magnets.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL314137X | 1952-09-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB744647A true GB744647A (en) | 1956-02-08 |
Family
ID=19783746
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB24508/53A Expired GB744647A (en) | 1952-09-09 | 1953-09-04 | Improvements in or relating to magnetic electron lenses and pole pieces for use therein |
Country Status (7)
| Country | Link |
|---|---|
| US (2) | US2910589A (en) |
| BE (1) | BE522628A (en) |
| CH (1) | CH314137A (en) |
| DE (1) | DE927524C (en) |
| FR (1) | FR1106673A (en) |
| GB (1) | GB744647A (en) |
| NL (1) | NL85195C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3019876A (en) * | 1960-01-06 | 1962-02-06 | Rabinow Engineering Co Inc | Fast response magnetic friction clutch |
| US3396299A (en) * | 1964-06-15 | 1968-08-06 | Jeol Ltd | Magnetic flux leakage guide for magnetic electron lenses |
| US4469948A (en) * | 1982-01-26 | 1984-09-04 | The Perkin-Elmer Corp. | Composite concentric-gap magnetic lens |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1132016A (en) * | 1912-01-24 | 1915-03-16 | John g burns | Means for forming zones of varying and variable strengths in magnetic fields. |
| US1121859A (en) * | 1912-11-08 | 1914-12-22 | Electric Weighing Company | Composite magnetizable material. |
| US2053162A (en) * | 1936-02-18 | 1936-09-01 | Gen Electric | Core for dynamo-electric machines |
| US2370627A (en) * | 1940-10-16 | 1945-03-06 | Rca Corp | Magnetic lens |
| US2418432A (en) * | 1944-05-01 | 1947-04-01 | Rca Corp | Magnetic electron lens system |
| US2719240A (en) * | 1946-03-14 | 1955-09-27 | Laurence R Walker | Cathode structure |
-
0
- NL NL85195D patent/NL85195C/xx active
- BE BE522628D patent/BE522628A/xx unknown
- US US927524D patent/UST927524I4/en active Pending
-
1953
- 1953-09-04 GB GB24508/53A patent/GB744647A/en not_active Expired
- 1953-09-06 DE DEN7703A patent/DE927524C/en not_active Expired
- 1953-09-07 CH CH314137D patent/CH314137A/en unknown
- 1953-09-07 FR FR1106673D patent/FR1106673A/en not_active Expired
- 1953-09-08 US US378990A patent/US2910589A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| FR1106673A (en) | 1955-12-21 |
| UST927524I4 (en) | |
| NL85195C (en) | |
| US2910589A (en) | 1959-10-27 |
| DE927524C (en) | 1955-05-12 |
| BE522628A (en) | |
| CH314137A (en) | 1956-05-31 |
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