US3899780A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic bubble store having optical centering apparatus
Assignee: US Philips Corp
•
Filing: 1974-01-30
•
Granted: 1975-08-12
•
Expires: 1994-01-30
Abstract
Abstract A storage system comprising a plate of magnetic material with a two-dimensional regular array of positions. A domain can be written and read in each of said positions by means of electromagnetic radiation. The electromagnetic radiation is generated by a highly coherent light source which can be modulated, for example, a laser. If they are not to be rased, the domains are maintained under the influence of a constant magnetic field which is generated by a permanent magnetic layer. Written domains are fixed to one of said positions in that the plate of magnetic material locally comprises a recess.
Inventors
- 👤 Matti Niilo Tapani Otala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:34
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/38; G11B23/40; G11B7/00; G11B7/08; G11B7/09; G11B7/0901; G11B7/0903; G11C; G11C13/00; G11C13/04; G11C13/06
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
184 words
A storage system comprising a plate of magnetic material, said magnetic material being provided with a regular twodimensional array of first recesses, said first recesses forming in cooperation with said magnetic material magnetically active elements for storing digital information in the form of magnetic bubbles, write means comprising an electromagnetic radiation source for locally heating the magnetically active elements whereby the magnetic bubbles are formed, means for maintaining a magnetic bias field in the vicinity of said magnetically active elements, the magnitude of the field determining the bubbles dimensions, electromagnetic read means for detecting said bubbles, addressing means for directing said read means and the said read write means to scan a selected magnetically active area, said plate being further provided with second recesses elongated in the direction in which said magnetically active areas are scanned, said second recesses forming a regular twodimensional array with said first recesses, and optical centering means for directing electromagnetic radiation to said second recesses and for centering said plate with respect to said read means and said write means in response to said radiation from said second recesses.
Claim 2
Dependent Claim
184 words
A storage system comprising a plate of magnetic material, said magnetic material being provided with a regular twodimensional array of first recesses, said first recesses forming in cooperation with said magnetic material magnetically active elements for storing digital information in the form of magnetic bubbles, write means comprising an electromagnetic radiation source for locally heating the magnetically active elements whereby the magnetic bubbles are formed, means for maintaining a magnetic bias field in the vicinity of said magnetically active elements, the magnitude of the field determining the bubbles dimensions, electromagnetic read means for detecting said bubbles, addressing means for directing said read means and the said read write means to scan a selected magnetically active area, said plate being further provided with second recesses elongated in the direction in which said magnetically active areas are scanned, said second recesses forming a regular twodimensional array with said first recesses, and optical centering means for directing electromagnetic radiation to said second recesses and for centering said plate with respect to said read means and said write means in response to said radiation from said second recesses.
Claim 3
Dependent Claim
41 words
A storage system as claimed in claim 1, wherein said plate comprises a disc, further comprising drive means for rotating said disc at a substantially uniform speed, the first and second recesses being arranged according to at least substantially circular tracks.
Claim 4
Dependent Claim
20 words
A storage system as claimed in claim 1, wherein additional information is contained in a dimension of the second recesses.
Claim 5
Dependent Claim
33 words
A storage system as claimed in claim 1, wherein said means for maintaining a magnetic bias field comprises a layer of permaneNt magnetic material which is provided on the plate of magnetic material.
Claim 6
Dependent Claim
161 words
A storage system comprising a plate of magnetic material, said magnetic material being provided with a regular two-dimensional array of recesses, said recesses forming in cooperation with said magnetic material magnetically active elements for storing digital information in the form of magnetic bubbles, write means comprising an electromagnetic radiation source for locally heating the magnetically active elements whereby the magnetic bubbles are formed, means for maintaining a magnetic bias field in the vicinity of said magnetically active elements, the magnitude of the field determining the bubbles dimensions, electromagnetic read means for detecting said bubbles, addressing means for directing said read means and said write means to scan a selected magnetically active area, said recesses being elongated in the direction in which said magnetically active areas are scanned, and optical scanning means for directing electromagnetic radiation to said recesses and for centering the plate with respect to said read means and said write means in response to said radiation from said recesses.
Claim 7
Dependent Claim
161 words
A storage system comprising a plate of magnetic material, said magnetic material being provided with a regular two-dimensional array of recesses, said recesses forming in cooperation with said magnetic material magnetically active elements for storing digital information in the form of magnetic bubbles, write means comprising an electromagnetic radiation source for locally heating the magnetically active elements whereby the magnetic bubbles are formed, means for maintaining a magnetic bias field in the vicinity of said magnetically active elements, the magnitude of the field determining the bubbles dimensions, electromagnetic read means for detecting said bubbles, addressing means for directing said read means and said write means to scan a selected magnetically active area, said recesses being elongated in the direction in which said magnetically active areas are scanned, and optical scanning means for directing electromagnetic radiation to said recesses and for centering the plate with respect to said read means and said write means in response to said radiation from said recesses.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |