US4587643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Disc playback apparatus
Assignee: Sony Corp
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Filing: 1984-08-27
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Granted: 1986-05-06
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Expires: 2004-08-27
Abstract
Abstract Apparatus permits the use of a known optical compact audio disc for providing a larger memory capacity so that data other than audio data can be reproduced therefrom while maintaining consistency with respect to signal format and signal processing, such as error correcting methods and recording data formats and the like, by providing write clock signals and read-out clock signals for reading into and out two memories the main digital data signal by using a subdigital data signal that is recorded on the disc along with the main digital data and which is reproduced from the disc at the same time as the main data in order to provide addressing of the main digital data on a more accurate level and with finer resolution, and a control system searches a playback location of the main digital data based upon the subdigital data as read out from the buffer memory, in which subdigital data has been written by the write clock signal.
Inventors
- 👤 Marinus J. B. M. Monen
- 👤 Shunsuke Furukawa
- 👤 Tsuneo Furuya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:57
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/10527; G11B20/18; G11B20/1806; G11B20/1809; G11B27/00; G11B27/10; G11B27/102; G11B27/105; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B27/3063; G11B7/00; G11B7/004; G11B7/005; G11B7/007; G11B7/013; G11B2020/10537; G11B2020/10592; G11B2220/00; G11B2220/20; G11B2220/25; G11B2220/2537; G11B2220/2545; G11B27/02; G11B27/031; G11B27/034; Y; Y10; Y10S; Y10S358/00; Y10S358/907
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
186 words
Apparatus for use in a system for reproducing a digital information signal including main digital data and subdigital data from an optical digital disc, the main digital data and subdigital data having been recorded together in a common track, comprising: means connected to receive an information signal reproduced from said disc for generating a write clock signal synchronized therewith; means for generating a readout clock signal having a fixed period; first memory means connected to receive said main digital data reproduced from said disc and being connected for writing therein said main digital data in response to said write clock signal, said first memory means being connected for reading out main digital data written therein in response to said readout clock signal; second memory means connected to write therein said subdigital data reproduced from said disc in response to said write clock signal and arranged for reading out said subdigital data written therein in response to said readout clock signal; and control means for searching a playback location of the main digital data in response to said subdigital data read out from said second memory mean.
Claim 2
Dependent Claim
186 words
Apparatus for use in a system for reproducing a digital information signal including main digital data and subdigital data from an optical digital disc, the main digital data and subdigital data having been recorded together in a common track, comprising: means connected to receive an information signal reproduced from said disc for generating a write clock signal synchronized therewith; means for generating a readout clock signal having a fixed period; first memory means connected to receive said main digital data reproduced from said disc and being connected for writing therein said main digital data in response to said write clock signal, said first memory means being connected for reading out main digital data written therein in response to said readout clock signal; second memory means connected to write therein said subdigital data reproduced from said disc in response to said write clock signal and arranged for reading out said subdigital data written therein in response to said readout clock signal; and control means for searching a playback location of the main digital data in response to said subdigital data read out from said second memory mean.
Claim 3
Dependent Claim
27 words
Apparatus according to claim 1, in which said first memory means includes decoder means for decoding an error correction code contained in said main digital data signal.
Claim 4
Dependent Claim
16 words
Apparatus according to claim 1, in which said first memory means comprises a random access memory.
Claim 5
Dependent Claim
15 words
Apparatus according to claim 1, in which said second memory means comprises a buffer memory.
Claim 6
Dependent Claim
31 words
Apparatus according to claim 1, further comprising means for coding said subdigital data with a timing signal having values continuously changing in accordance with locations in the track on the disc.
Claim 7
Dependent Claim
39 words
Apparatus according to claim 1, further comprising demodulating means connected to receive said reproduced main digital data for demodulating a block pattern having a first number of bits to a block pattern having a second, lesser number of bits.
Claim 8
Dependent Claim
28 words
Apparatus according to claim 6, further comprising clock extraction circuit means receiving said reproduced main digital data and extracting a clock signal therefrom fed to said demodulating means.
Claim 9
Dependent Claim
30 words
Apparatus according to claim 7, further comprising a FRAME synchronization detection circuit receiving said reproduced main digital data signal and producing a FRAME sync signal fed to said demodulating means.
Claim 10
Dependent Claim
38 words
Apparatus according to claim 1, in which said control means comprises a random access memory controller operably connected to an error correction circuit for correcting time base errors and data errors in said reproduced main digital data signal.
Claim 11
Dependent Claim
24 words
Apparatus according to claim 1, further comprising a microcomputer operably connected to said control means for providing addresses corresponding to said respective playback locations.
Claim 12
Dependent Claim
20 words
Apparatus according to claim 10, in which said addresses are separated a predetermined data distance from said respective playback locations.
Claim 13
Dependent Claim
18 words
Apparatus according to claim 11, further comprising an interface unit arranged between said microcomputer and said control means.
Claim 14
Dependent Claim
208 words
Apparatus for use in reproducing digital information including main digital data and subdigital data, from an optical digital disc, in which the main digital data and the subdigital data are recorded in a common track on the disc, comprising: means connected to receive digital information reproduced from said disc for generating a write clock signal synchronized with the reproduction rate of the digital information; an oscillator for generating a readout clock signal having a fixed period; means for separating the main digital data and the subdigital data from the reproduced information signal; a random access memory connected to receive said main digital data reproduced from said disc and being connected for writing therein said main digital data in response to said write clock signal, said random access memory being connected for reading out main digital data written therein in response to said readout clock signal; a buffer memory connected to write therein said subdigital data reproduced from said disc in response to said write clock signal and arranged for reading out said subdigital data written therein in response to said readout clock signal; and control means for searching a playback location of the main digital data in response to said subdigital data read out from said buffer memory.
Claim 15
Dependent Claim
208 words
Apparatus for use in reproducing digital information including main digital data and subdigital data, from an optical digital disc, in which the main digital data and the subdigital data are recorded in a common track on the disc, comprising: means connected to receive digital information reproduced from said disc for generating a write clock signal synchronized with the reproduction rate of the digital information; an oscillator for generating a readout clock signal having a fixed period; means for separating the main digital data and the subdigital data from the reproduced information signal; a random access memory connected to receive said main digital data reproduced from said disc and being connected for writing therein said main digital data in response to said write clock signal, said random access memory being connected for reading out main digital data written therein in response to said readout clock signal; a buffer memory connected to write therein said subdigital data reproduced from said disc in response to said write clock signal and arranged for reading out said subdigital data written therein in response to said readout clock signal; and control means for searching a playback location of the main digital data in response to said subdigital data read out from said buffer memory.
Claim 16
Dependent Claim
21 words
Apparatus according to claim 13, further comprising decoder means for decoding an error correction code contained in said main digital data.
Claim 17
Dependent Claim
32 words
Apparatus according to claim 13, further comprising means for coding said subdigital data with a timing signal having values continuously changing in accordance with playback locations in the track on the disc.
Claim 18
Dependent Claim
23 words
Apparatus according to claim 13, in which said means for separating said main digital data and said subdigital data comprises an EFM demodulator.
Claim 19
Dependent Claim
31 words
Apparatus according to claim 16, in which said EFM demodulator transforms a block pattern having a first number of bits to a block pattern having a second lesser number of bits.
Claim 20
Dependent Claim
28 words
Apparatus according to claim 17, further comprising clock extraction circuit means receiving said reproduced main digital data and extracting a clock signal therefrom fed to said EFM demodulator.
Claim 21
Dependent Claim
30 words
Apparatus according to claim 18, further comprising a FRAME synchronization detection circuit receiving said reproduced main digital data signal and producing a FRAME sync signal fed to said EFM demodulator.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-05 | 1989-11-04 | 1990-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-05 | 1993-11-04 | 1994-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-05 | 1997-11-04 | 1998-05-06 | $7700.00 | Window Closed / Lapsed |