Patent US3760383A successfully refreshed from Google Patents.
US3760383A
Expired / Lapsed
US
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Erration storage system with collimated electron beam for minimal spherical ab
Assignee: General Electric Co
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Filing: 1971-07-01
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Granted: 1973-09-18
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Expires: 1991-07-01
Abstract
Abstract A storage system for the mass recording and readout of digital data with ultra high resolution. An electron beam structure is provided for forming a beam of extremely small focused spot diameter, on the order of 0.1 microns, and high current density capability, on the order of 1,000 amperes per sq. cm., which records data by scanning over defined areas of the storage medium surface and micromachining elemental portions of said medium as a function of beam modulation. Readout may be subsequently accomplished by similarly scanning the beam at reduced power density and detecting electrons that have been transmitted by or reflected from the storage medium.
Inventors
- 👤 H Glascock
- 👤 J Wolfe
- 👤 G Ledge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:54
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/02; H01J37/04; H01J37/06; H01J37/073; G; G11; G11C; G11C13/00; G11C13/04; G11C13/048; H01J2237/00; H01J2237/06; H01J2237/063; H01J2237/06308; H01J2237/06316
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
285 words
An electron beam high density storage system providing storage of information on a storage medium and subsequent retrieval of said information, comprising: a. an evacuated chamber, b. a storage medium modifiable upon electron beam impingement, c. cathode means within said chamber including a rigidly supported cathode needle structure, the tip of which provides an extremely small dimensioned emissive surface, d. field means within said chamber for providing a generally radial electric field centered about the cathode needle emissive tip with a sufficiently high electric field gradient in the vicinity of said emissive tip for field emission, ssid cathode means and said field means producing a high density emission current formed into a beam having a divergent configuration, e. a first focus lens for transposing the divergent configuration of said beams into a convergent configuration, f. a second focus lens for transposing the collimated configuration of said beam into a convergent configuration, said two lenses thereby having minimal spherical aborration and, the virtual image of said tip being thereby focused on the surface of said storage medium as an extremely small spot with high current density, said storage medium comprising an array of discrete data blocks, each of limited surface area, g. mechanical drive means for moving said storage medium so as to singly position selected data blocks under the focused beam, h. deflection means for deflecting said beam over the surface area of said selected data blocks, i. modulation means for modulating the beam as it is deflected over the limited surface area of said selected data blocks for writing information upon said storage medium as a function of the modulations, and j. readout means within said chamber for retrieving information that has been written.
Claim 2
Dependent Claim
285 words
An electron beam high density storage system providing storage of information on a storage medium and subsequent retrieval of said information, comprising: a. an evacuated chamber, b. a storage medium modifiable upon electron beam impingement, c. cathode means within said chamber including a rigidly supported cathode needle structure, the tip of which provides an extremely small dimensioned emissive surface, d. field means within said chamber for providing a generally radial electric field centered about the cathode needle emissive tip with a sufficiently high electric field gradient in the vicinity of said emissive tip for field emission, ssid cathode means and said field means producing a high density emission current formed into a beam having a divergent configuration, e. a first focus lens for transposing the divergent configuration of said beams into a convergent configuration, f. a second focus lens for transposing the collimated configuration of said beam into a convergent configuration, said two lenses thereby having minimal spherical aborration and, the virtual image of said tip being thereby focused on the surface of said storage medium as an extremely small spot with high current density, said storage medium comprising an array of discrete data blocks, each of limited surface area, g. mechanical drive means for moving said storage medium so as to singly position selected data blocks under the focused beam, h. deflection means for deflecting said beam over the surface area of said selected data blocks, i. modulation means for modulating the beam as it is deflected over the limited surface area of said selected data blocks for writing information upon said storage medium as a function of the modulations, and j. readout means within said chamber for retrieving information that has been written.
Claim 3
Dependent Claim
42 words
A storage system as in claim 1 wherein said cathode means includes a filamentary heating means for aiding emission, and meAns for continuously supplying a very thin coating to said tip of a material that reduces the work function at said tip.
Claim 4
Dependent Claim
52 words
A storage system as in claim 2 wherein said emissive tip is in a plane at about the focal point of said first lens, and said storage medium surface is in a plane at about the focal point of said second lens so as to reduce effective spherical aberration of said lenses.
Claim 5
Dependent Claim
54 words
A storage system as in claim 3 wherein said field means includes a grid electrode having an aperture through which said cathode needle protrudes, and an anode electrode positioned forward of said cathode emissive tip, having an aperture coaxially related to said cathode needle through which the central portion of said beam is directed.
Claim 6
Dependent Claim
81 words
A storage system as in claim 4 wherein said modulation means shifts the beam so as to be recurrently intercepted by said apertured electrode structure as a function of the modulations, whereby the emission density may be maintained constant as the current density at the storage medium surface is varied and wherein said readout means includes an electron detector which responds to electrons received from said storage medium in response to impingement by said beam when operated at reduced current densities.
Claim 7
Dependent Claim
39 words
A storage system as in claim 5 in which the focused beam spot possesses a diameter on the order of 0.1 microns and less with a current density on the order of 1,000 amperes per sq. cm. and greater.
Claim 8
Dependent Claim
32 words
A storage system as in claim 6 in which said storage medium is composed of a selenium composition, portions of which are selectively vaporized by the focused beam during the writing operation.
Claim 9
Dependent Claim
240 words
An electron beam high density storage system providing storage of information on a storage medium and subsequent retrieval of said information, comprising: a. an evacuated chamber, b. a storage medium modifiable upon electron beam impingement c. cathode means within said chamber including a rigidly supported cathode needle structure, the tip of which provides an extremely small dimensioned emissive surface, d. field means within said chamber for providing a generally radial electric field centered about the cathode needle emissive tip with a sufficiently high electric field gradient in the vicinity of said emissive tip for field emission, said cathode means and said field means producing a high density emission current formed into a beam having a divergent configuration, e. a first focus lens for transposing the divergent configuration of said beam into a collimated configuration, f. a second focus lens for transposing the collimated configuration said two lenses thereby having minimal spherical aborration and, of said beam into a convergent configuration, the virtual image of said tip being thereby focused on the surface of said storage medium as an extremely small spot with high current density, g. deflection means for deflecting said beam over said storage medium surface, h. modulation means for modulating the beam as it is deflected over the storage medium surface for writing information upon said storage, medium as a function of the modulations, and i. readout means within said chamber for retrieving information that has been written.
Claim 10
Dependent Claim
240 words
An electron beam high density storage system providing storage of information on a storage medium and subsequent retrieval of said information, comprising: a. an evacuated chamber, b. a storage medium modifiable upon electron beam impingement c. cathode means within said chamber including a rigidly supported cathode needle structure, the tip of which provides an extremely small dimensioned emissive surface, d. field means within said chamber for providing a generally radial electric field centered about the cathode needle emissive tip with a sufficiently high electric field gradient in the vicinity of said emissive tip for field emission, said cathode means and said field means producing a high density emission current formed into a beam having a divergent configuration, e. a first focus lens for transposing the divergent configuration of said beam into a collimated configuration, f. a second focus lens for transposing the collimated configuration said two lenses thereby having minimal spherical aborration and, of said beam into a convergent configuration, the virtual image of said tip being thereby focused on the surface of said storage medium as an extremely small spot with high current density, g. deflection means for deflecting said beam over said storage medium surface, h. modulation means for modulating the beam as it is deflected over the storage medium surface for writing information upon said storage, medium as a function of the modulations, and i. readout means within said chamber for retrieving information that has been written.
Claim 11
Dependent Claim
42 words
A storage system as in claim 8 wherein said cathode means includes a filamentary heating means for aiding emission, and means for continuously supplying a very thin coating to said tip of a material that reduces the work function at said tip.
Claim 12
Dependent Claim
52 words
A storage system as in claim 9 wherein said emissive tip is in a plane at about the focal point of said first lens, and said storage medium surface is in a plane at about the focal point of said second lens so as to reduce effective spherical aberration of said lenses.
Claim 13
Dependent Claim
54 words
A storage system as in claim 10 in which said field means includes a grid electrode having an aperture through which said cathode needle protrudes and an anode electrode positioned forward of said emissive tip haviNg an aperture coaxially related to said cathode needle, through which the central portion of said beam is directed.
Claim 14
Dependent Claim
26 words
A storage system as in claim 11 wherein said first and second focus lenses each comprise a magnetic coil wound about the circumference of said chamber.
Claim 15
Dependent Claim
66 words
A storage system as in claim 12 wherein said deflection means is positioned between said second focus lens and said storage medium, and wherein said modulating means shifts the beam so as to be recurrently intercepted by said apertured electrode structure as a function of the modulations, whereby the emission density may be maintained constant as the current density at the storage medium surface is varied.
Claim 16
Dependent Claim
37 words
A storage system as in claim 13 wherein said readout means includes an electron detector which responds to electrons received from said storage medium in response to impingement by said beam when operated at reduced current densities.
Claim 17
Dependent Claim
39 words
A storage system as in claim 14 in which the focused beam spot possesses a diameter on the order of 0.1 microns and less with a current density on the order of 1,000 amperes per sq. cm. and greater.
Claim 18
Dependent Claim
33 words
A storage system as in claim 15 in which said storage medium is composed primarily of a selenium composition, portions of which are selectively vaporized by the focused beam during the writing operation.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |