US3324433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electron lens system excited by at least one permanent magnet
Assignee: Hitachi Ltd
•
Filing: 1964-12-28
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Granted: 1967-06-06
•
Expires: 1984-12-28
Abstract
No abstract record available.
Inventors
- 👤 Kimura Hirokazu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:26
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/02; H01J37/04; H01J37/10; H01J37/14; H01J37/143
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
139 words
AN ELECTRON LENS SYSTEM EXCITED BY PERMANENT MAGNET MEANS COMPRISING AT LEAST ONE PERMANENT MAGNET HAVING A BORE THROUGH ITS CENTER FOR PASSAGE OF AN ELECTRON BEAM AND BEING AXIALLY MAGNETIZED; AN UPPER AND A LOWER POLE PIECE ABOVE AND BELOW SAID MAGNET, RESPECTIVELY, OF MAGNETIC MATERIAL WITH HIGH PERMEABILITY, BOTH ALIGNED COAXIALLY AND RADIALLY WITH SAID MAGNET, PROVIDED WITH FLANGES AND HAVING A CENTER BORE CONTINUING THE BORE OF SAID MAGNET; AT LEAST ONE AIR SPACE BETWEEN SAID MAGNET AND SAID POLE PIECES, WHEREBY ACTIVE MAGNETIC FIELDS ARE PRODUCED SUBSTANTIALLY IN THE AREA OF SAID BORES, SAID SPACE AND SAID POLE PIECES; AND AN OUTER CYLINDER MAGNETICALLY CONNECTED TO SAID FLANGES, COMPLETELY ENCLOSING SAID MAGNET AND DISPOSED SYMMETRICALLY WITH RESPECT TO SAID PASSAGE OF THE ELECTRON BEAM, PRODUCING A SHIELDING EFFECT WHILE SIMULTANEOUSLY FORMING A CLOSED MAGNETIC PATH.
Claim 2
Dependent Claim
139 words
AN ELECTRON LENS SYSTEM EXCITED BY PERMANENT MAGNET MEANS COMPRISING AT LEAST ONE PERMANENT MAGNET HAVING A BORE THROUGH ITS CENTER FOR PASSAGE OF AN ELECTRON BEAM AND BEING AXIALLY MAGNETIZED; AN UPPER AND A LOWER POLE PIECE ABOVE AND BELOW SAID MAGNET, RESPECTIVELY, OF MAGNETIC MATERIAL WITH HIGH PERMEABILITY, BOTH ALIGNED COAXIALLY AND RADIALLY WITH SAID MAGNET, PROVIDED WITH FLANGES AND HAVING A CENTER BORE CONTINUING THE BORE OF SAID MAGNET; AT LEAST ONE AIR SPACE BETWEEN SAID MAGNET AND SAID POLE PIECES, WHEREBY ACTIVE MAGNETIC FIELDS ARE PRODUCED SUBSTANTIALLY IN THE AREA OF SAID BORES, SAID SPACE AND SAID POLE PIECES; AND AN OUTER CYLINDER MAGNETICALLY CONNECTED TO SAID FLANGES, COMPLETELY ENCLOSING SAID MAGNET AND DISPOSED SYMMETRICALLY WITH RESPECT TO SAID PASSAGE OF THE ELECTRON BEAM, PRODUCING A SHIELDING EFFECT WHILE SIMULTANEOUSLY FORMING A CLOSED MAGNETIC PATH.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-06-05 | 1970-12-05 | 1971-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-06-05 | 1974-12-05 | 1975-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-06-05 | 1978-12-05 | 1979-06-06 | $7700.00 | Window Closed / Lapsed |