Patent US3723978A successfully refreshed from Google Patents.
US3723978A
Expired / Lapsed
US
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Beam addressable memory apparatus
Assignee: 3M Co
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Filing: 1971-03-01
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Granted: 1973-03-27
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Expires: 1991-03-01
Abstract
Abstract Beam addressable memory apparatus including an electron gun having a compound electrostatic immersion gun lens, a first set of electrostatic deflection plates, and a compound electrostatic immersion objective lens for writing charged bits of information on a storage media. During the reading mode, the storage media is negatively biased to mirror and spacially modulate the electron beam. The mirrored beam is passed back through the objective lens, a second set of electrostatic deflection plates, and a projector lens onto a detector array for producing simultaneous digital electrical signals corresponding to the bit pattern on the media.
Inventors
- 👤 K Maffitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:08
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/23; H; H01; H01J; H01J31/00; H01J31/08; H01J31/58; H01J31/60
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
153 words
An information retrieval apparatus providing simultaneous read-out of a plurality of information bits, comprising a. a medium having a plurality of information areas wherein each said area includes a distribution of information sites arranged in a predetermined pattern, said medium being capable of having information bits at said sites forming a bit pattern; b. electron means for producing substantially monoenergetic electrons formed into an electron beam having a controlled cross section of sufficient area to be affected by said information sites within an information area; c. deflection means for directing said electron beam toward a first information area; d. means for negatively biasing said medium to mirror and spacially modulate the density of said mirrored beam in an arrangement corresponding to the stored bit pattern on said medium; and e. detector means to convert the density modulations simultaneously of said mirrored beam to electrical signals corresponding to the bit pattern on said medium.
Claim 2
Dependent Claim
153 words
An information retrieval apparatus providing simultaneous read-out of a plurality of information bits, comprising a. a medium having a plurality of information areas wherein each said area includes a distribution of information sites arranged in a predetermined pattern, said medium being capable of having information bits at said sites forming a bit pattern; b. electron means for producing substantially monoenergetic electrons formed into an electron beam having a controlled cross section of sufficient area to be affected by said information sites within an information area; c. deflection means for directing said electron beam toward a first information area; d. means for negatively biasing said medium to mirror and spacially modulate the density of said mirrored beam in an arrangement corresponding to the stored bit pattern on said medium; and e. detector means to convert the density modulations simultaneously of said mirrored beam to electrical signals corresponding to the bit pattern on said medium.
Claim 3
Dependent Claim
40 words
An information retrieval apparatus according to claim 1 wherein said retrieval apparatus includes an address selector connected to said deflection means to selectively direct said electron beam toward a second information area to permit random access of desired information areas.
Claim 4
Dependent Claim
32 words
An information retrieval apparatus according to claim 2 wherein said retrieval apparatus includes feed-back means for detecting errors in beam registration and correcting the position of said electron beam at said medium.
Claim 5
Dependent Claim
23 words
An information retrieval apparatus according to claim 1 wherein said electron means includes an electron gun producing a substantial current of monoenergetic electrons.
Claim 6
Dependent Claim
25 words
An information retrieval apparatus according to claim 1 wherein said electron means includes an objective lens means receiving said electron beam from said deflection means.
Claim 7
Dependent Claim
23 words
An information retrieval apparatus according to claim 5 wherein said objective lens means includes a positively biased apertured plate adjacent to said medium.
Claim 8
Dependent Claim
35 words
An information retrieval apparatus according to claim 5 wherein said objective lens means includes a compound electrostatic immersion lens formed of first, second and third plates spaced from each other and having coaxially aligned apertures.
Claim 9
Dependent Claim
33 words
An information retrieval apparatus according to claim 1 wherein said detector means includes a detector array formed of a plurality of individual detectors having a pattern corresponding to the distribution of information sites.
Claim 10
Dependent Claim
47 words
An information retrieval apparatus according to claim 8 wherein said detector array is physically enlarged relative to the distribution of information sites, and wherein said apparatus includes projector lens means for enlarging the diameter of said mirrored electron beam prior to said beam reaching said detector array.
Claim 11
Dependent Claim
34 words
An information retrieval apparatus according to claim 9 wherein said retrieval apparatus includes magnetic field means in front of said objective lens for causing separation of said mirrored electron beam from said electron beam.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |