DK166054B - Automatic correction system for the servo-circuit in a device with optical scanning of a rotating information support - Google Patents
Automatic correction system for the servo-circuit in a device with optical scanning of a rotating information support Download PDFInfo
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- DK166054B DK166054B DK614286A DK614286A DK166054B DK 166054 B DK166054 B DK 166054B DK 614286 A DK614286 A DK 614286A DK 614286 A DK614286 A DK 614286A DK 166054 B DK166054 B DK 166054B
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- DK
- Denmark
- Prior art keywords
- counter
- signal
- correction
- servo
- correction system
- Prior art date
Links
- 230000003287 optical effect Effects 0.000 title claims description 4
- 239000000969 carrier Substances 0.000 claims description 2
- 230000000694 effects Effects 0.000 description 5
- 230000035939 shock Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 238000013479 data entry Methods 0.000 description 2
- 230000004913 activation Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B21/00—Head arrangements not specific to the method of recording or reproducing
- G11B21/02—Driving or moving of heads
- G11B21/10—Track finding or aligning by moving the head ; Provisions for maintaining alignment of the head relative to the track during transducing operation, i.e. track following
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0948—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for detection and avoidance or compensation of imperfections on the carrier, e.g. dust, scratches, dropouts
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B21/00—Head arrangements not specific to the method of recording or reproducing
- G11B21/02—Driving or moving of heads
- G11B21/10—Track finding or aligning by moving the head ; Provisions for maintaining alignment of the head relative to the track during transducing operation, i.e. track following
- G11B21/106—Track finding or aligning by moving the head ; Provisions for maintaining alignment of the head relative to the track during transducing operation, i.e. track following on disks
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0946—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for operation during external perturbations not related to the carrier or servo beam, e.g. vibration
Landscapes
- Optical Recording Or Reproduction (AREA)
- Moving Of The Head To Find And Align With The Track (AREA)
- Facsimile Scanning Arrangements (AREA)
Description
iin
DK 166054 BDK 166054 B
Den foreliggende opfindelse angår et automatisk korrektionssystem i henhold til krav l's indledning.The present invention relates to an automatic correction system according to the preamble of claim 1.
Aftastningen af roterende informationsbærere med optiske aftastere 5 kan forstyrres på forskellig måde. CD-afspiliere reagerer eksempelvis på ydre stød på lignende måde som på ridser eller lignende fejl på pladen, der skal aftastes. Der indtræder enten sportab, eller i det mindste vil aftastningssystemet ved støjstedet springe et spor fremad eller bagud. Ved sammenbrud af det tilstedeværende 10 servosystem detekteres denne tilstand ved den kendte teknik, og en tilsvarende nyaktivering indledes. I løbet af denne tid bliver audiodataene stum-styret (Mute) for at undgå ubehagelig forstyrrende støj.The scanning of rotary information carriers with optical sensors 5 can be disrupted in various ways. CD players, for example, react to external shocks in a similar way as to scratches or similar errors on the disc to be scanned. Either sport loss occurs, or at least the sensing system at the noise site will skip a track forward or backward. Upon breakdown of the present servo system, this state is detected by the prior art and a corresponding new activation is initiated. During this time, the audio data is muted (Mute) to avoid unpleasant interfering noise.
15 Efter stabiliseringen af reguleringskredsene bliver stumstyringen igen ophævet. Ulempen ved denne teknik er, at ved sammenbruddet af servosystemet og også i det andet nævnte støjtilfælde går det momentane eller sidste gyldige aftastningspunkt tabt, og efter udløbet af støjfasen eller afslutningen af støj indvirkningen fort-20 sættes ved et eller andet tilfældigt aftastningspunkt. Dette bevirker, at ikke kun afbrydelser på grund af stumomskiftningen er hørbare, men at regulære informationsforskydninger betinget af det tilfældige påsætningspunkt gør sig meget generende bemærket.15 After the stabilization of the control circuits, the mute control is again removed. The disadvantage of this technique is that in the breakdown of the servo system and also in the second mentioned noise case, the instant or last valid scan point is lost and after the noise phase or the end of the noise the effect continues at some random scan point. This means that not only interruptions due to the mute switching are audible, but that regular information offsets contingent on the random point of attachment become very troublesome.
25 I patentansøgning GB 2060217A er det på side 10, første afsnit vist, hvorledes et sporfejlkorrektionssystem arbejder ved to bestemte fejltyper, nemlig når man "bliver hængende" ("locked groove or track") og ved "fremadspring" ("skipped forward"). Til begge tilfælde foreslås styrealgoritmer. Ud fra denne kendte teknik er det 30 også allerede kendt ved sammenkoblingstypen af servosystemets kredsløbsdele alt efter valg af størrelsen af forud fastsættelsen såvel som størrelsen af en tællerstand at foretage en efter fejltypen og virkningen på aftasteren tilpasset korrektion. Det første tilfælde indtræder navnlig ved aftastningen af CD-plader, som har 35 pladefejl, såsom ridser eller "black dots". Det andet tilfælde optræder navnlig ved stød udefra mod apparatet.25 In patent application GB 2060217A, on page 10, first paragraph, it is shown how a track error correction system works for two specific types of errors, namely when "locked groove or track" and "skipped forward" . For both cases, control algorithms are proposed. From this prior art, it is also already known in the interconnection type of the circuit parts of the servo system, depending on the size of the preset as well as the size of a counter stand, to make a correction according to the type of error and the effect on the sensor. The first case occurs especially when scanning CDs which have 35 disc errors, such as scratches or "black dots". The second case occurs in particular with external impact against the apparatus.
Formålet med den foreliggende opfindelse er for det første støjtilfælde, som kan føre til, at man "bliver hængende", at forbedre detThe object of the present invention is, firstly, to make a noise case which can lead to "getting stuck", to improve it.
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2 kendte korrektionssystem, således at der ikke indtræder noget tab af det sidste gyldige aftastningspunkt i tilfælde af en forstyrrelse, så at det med sikkerhed forhindres, at man "bliver hængende", og at gøre systemet så hurtigt reagerende, at der ved pladetypiske for-5 styrrelsestil fælde af de nævnte arter i vid udstrækning ikke kan konstateres noget akustisk, idet aftastningssystemet styres hen over forstyrrelsesstedet. Herfor skal servosystemet tilføres et positioneringssignal alt efter arten og størrelsen af fejlen.2, so that no loss of the last valid scan point occurs in the event of a disturbance, so that it is certainly prevented from "hanging", and to make the system so responsive that in plate type 5 acoustic cases of the said species are largely undetectable acoustically, since the sensing system is controlled over the disturbance site. For this, the servo system must be supplied with a positioning signal according to the nature and size of the fault.
10 Ifølge opfindelsen opnås dette ved at udføre korrekti onssysternet som angivet i krav l's kendetegnende del.According to the invention this is achieved by performing the correction system as set forth in the characterizing part of claim 1.
Yderligere enkeltheder og udformninger fremgår af underkravene og den efterfølgende beskrivelse af udførelseseksempler.Further details and designs are set forth in the subclaims and the following description of embodiments.
15 I henhold til opfindelsen fastholdes det sidste gyldige aftastningspunkt før begyndelsen af støjfasen, som detekteres af servospecifikke indikatorsignaler. Derpå dannes et til forstyrrelsen svarende korrektionssignal, som foretager en automatisk korrektion 20 på det sidste gyldige aftastningspunkt. Informationshuller bliver således undgået på fordelagtig måde. Når korrektionssystemet arbejder tilstrækkeligt hurtigt, er mute-faser praktisk taget næppe hørbare og følgelig ikke forstyrrende.According to the invention, the last valid scan point is maintained before the beginning of the noise phase, which is detected by servo-specific indicator signals. Then, a correction signal corresponding to the disturbance is generated which makes an automatic correction 20 at the last valid scanning point. Thus, information gaps are avoided in an advantageous way. When the correction system works fast enough, the mute phases are practically hardly audible and consequently not disturbing.
25 To udførelseseksempler skal herefter forklares nærmere under henvisning til tegningen, hvor fig. 1 et blokdiagram over et korrektionssystem ifølge kendt teknik, som er egnet til fejl på grund af ydre indvirkning, 30 og fig. 2 et blokdiagram over et korrektionssystem, som specielt er egnet til korrektion af fejl på grund af ridser eller lignende.Two embodiments will then be explained in more detail with reference to the drawing, in which fig. 1 is a block diagram of a prior art correction system suitable for external action errors; FIG. 2 is a block diagram of a correction system which is particularly suitable for the correction of errors due to scratches or the like.
35 Et udførelseseksempel på et automatisk korrektionssystem er vist i fig. 1. Hovedbestanddelene er blokke 6 (sammenligning + korrektion) og 7 (lager for aktuel subkode). I blok 7 bliver ved normal drift, dvs. aftastning til gengivelse uden forstyrrelse, til stadighed lagret den aktuelle adresseinformation over en blok 4 (datakontrol)35 An embodiment of an automatic correction system is shown in FIG. 1. The main components are blocks 6 (comparison + correction) and 7 (stock for current subcode). In block 7, during normal operation, i.e. scan for reproduction without interference, constantly storing the current address information over a block 4 (data control)
DK 166054 BDK 166054 B
3 og en portkobling 9. Så snart der optræder en forstyrrelse i servosystemet 3, aktiverer dette blokken 6 ved hjælp af identifikationssignalet "fokus-not-ok/Track-not-ok" over en lager-enhed 5.3 and a gate coupling 9. As soon as a disturbance occurs in the servo system 3, this activates the block 6 by means of the identification signal "focus-not-ok / Track-not-ok" over a storage unit 5.
Denne foranlediger over en ledning OK en øjeblikkelig spærring af 5 porten 9, så at yderligere dataindskrivning i lageret 7 ikke foreløbig er mulig. Endvidere bliver enheden 5 gjort inaktiv. Derved bliver signalet "fokus-not-ok/Track-not-ok” fastholdt i blok 5. Når servosystemet 3 efter en forstyrrelse igen har stabiliseret sig, og der følgelig igen overføres nye adressedata fra blok 4, sker sam-10 menligningen mellem gamle og nye data i blok 6, og der frembringes et korrektionssignal derved, som positionerer aftastningssystemet (pick-up-systemet) 1 på det sidste gyldige aftastningspunkt før forstyrrelsesstedet. Når denne værdi er opnået, afgiver sammenligningstrinnet 6 et "ok"-signal, som tilbagestiller lager-enheden 5 og 15 foranlediger en ny dataindskrivning over porten 9 i lageret 7. Dette sammenlignings- og korrektionssystem er specielt egnet til at afhjælpe forstyrrelser på grund af ydre indvirkninger, såsom chok eller stød, på den optiske aftastning.This causes, over a wire, an immediate blockage of port 9, so that further data entry in the storage 7 is not provisionally possible. Furthermore, the unit 5 is rendered inactive. Thereby, the signal "focus-not-ok / Track-not-ok" is retained in block 5. When the servo system 3 has stabilized again after a disturbance and consequently new address data from block 4 is transmitted again, the comparison between old ones and new data in block 6, thereby generating a correction signal which positions the scanning system (pick-up system) 1 at the last valid scanning point before the disturbance point. When this value is obtained, comparing step 6 emits an "ok" signal which resetting the storage unit 5 and 15 causes a new data entry over the port 9 in the storage 7. This comparison and correction system is particularly suitable for alleviating interference due to external effects, such as shock or shock, on the optical scan.
20 Fig. 2 viser et blokdiagram over et forbedret korrektionssystem, der ligesom systemet i fig. 1 bygger på et kendt servosystem og samarbejder med dette. Uden forstyrrelser bliver de aktuelle data, som er proportionale med aftastningspunktet, i den normale aftastningstilstand afgivet fra blokken data-check 4 og til stadig-25 hed lagt i et lager i blok 7a (D^y). En tæller 5a er derved i grundtilstanden og frikobler en port 9, så at data også til stadighed lagres i referencelageret 7b. Så længe der ikke optræder nogen forstyrrelse, er de aktuelle data samtidigt til stede i lagrene 7a og 7b, og andre kredsløbsdele er inaktive. Ved forstyrrelse af 30 aftastningen, når aftasteren (pick-up'en) 1 altså eksempelvis på grund af en ridse på sporet springer tilbage, afgiver servosystemet 3 et "not-ok"-signal, som aktiverer komparatoren 6a. Da lagrene 7a og 7b nu har ens data, afgiver komparatoren 6a et "ok"-signal til tælleren 5a, som tæller de på det samme sted mistede 35 aftastningspunkter.FIG. 2 shows a block diagram of an improved correction system which, like the system of FIG. 1 is based on a known servo system and cooperates with this. Without interruption, the current data proportional to the scan point is, in the normal scan state, delivered from the block of data-check 4 and permanently stored in a block in block 7a (D ^ y). A counter 5a is thereby in the basic state and disconnects a port 9 so that data is also continuously stored in the reference memory 7b. As long as there is no disturbance, the current data is simultaneously present in the bearings 7a and 7b and other circuit parts are inactive. In case of disturbance of the sensing, when the scanner (pick-up) 1, for example, due to a scratch on the track, returns, the servo system 3 emits a "not-ok" signal which activates the comparator 6a. Since the bearings 7a and 7b now have similar data, the comparator 6a outputs an "ok" signal to the counter 5a, which counts the lost 35 scan points at the same location.
Med andre ord bliver tælleren 5a forhøjet med 1, når der ved frigivelse af komparatoren 6a ved hjælp af NOT OK signalet fra servodelen 3 fås, at adressesammenligningen fra lagrene 7a og 7b er ens, og fraIn other words, the counter 5a is increased by 1 when upon releasing the comparator 6a by means of the NOT OK signal from the servo part 3, the address comparison from the bearings 7a and 7b is obtained, and from
DK 166054BDK 166054B
4 komparatoren 6a føres OK-signalet til tælleren 5a.4 the comparator 6a passes the OK signal to the counter 5a.
OK-signalet fra komparatoren 6a bliver kun frembragt, når sammenligningen af adressedataene D^j og D^p bliver opfyldt over NOT OK 5 signalet fra servodelen 3 altså D^y = D^p i det øjeblik, hvor NOT OK signalet frembringes af servodelen 3.The OK signal from comparator 6a is generated only when the comparison of the address data D ^ j and D ^ p is met over the NOT OK 5 signal from the servo part 3, thus D ^ y = D ^ p at the moment when the NOT OK signal is generated by the servo part 3 .
Et NOT OK signal bliver frembragt af servodelen 3, når aftastningen afbrydes af et forstyrrelsessted på pladen, der skal aftastes. Da 10 aftastningen straks begynder igen på et andet sted (eller punkt på pladen), afgiver også servodelen 3 straks igen et OK signal og spærrer komparatoren 6a.A NOT OK signal is generated by the servo part 3 when the scan is interrupted by a disturbance point on the plate to be scanned. As the scanning immediately begins again at another location (or point on the plate), the servo part 3 also immediately returns an OK signal and blocks the comparator 6a.
Tælleren 5a lader sig indstille på en overløbsværdi (n = forud 15 fastsætteligt antal på tælleren 5a), dvs. når overløb finder sted fås, at signalet "over" på tælleren 5a aktiverer korrektionssystemet 6b over "enable". Svarende til signalet D^y + Δ D gives servodelen 3 en korrektion D^, dvs. aftastningen bliver foretaget forsat fremad med Δ D i forhold til forstyrrelsesstedet.The counter 5a can be set to an overflow value (n = predetermined number on the counter 5a), ie. when overflow occurs, the signal "over" on the counter 5a activates the correction system 6b over "enable". Corresponding to the signal D ^ y + Δ D, the servo part 3 is given a correction D the scan is carried forward with Δ D relative to the point of interference.
20 I tilfælde af overløb η = n bliver tælleren 5a sat på nul, og dermed Λ bliver porten 9 også igen frigivet for yderligere lagringer af adresserne.In the case of overflow η = n, the counter 5a is set to zero and thus Λ the gate 9 is also released again for further storage of the addresses.
25 Sportab kan ske såvel på grund af pladefejl (ridser, tilsmudsning), som på grund af stød (imod apparatet). I det første tilfælde ville der ved et "tilbagespring" af aftasteren optræde en "gentage effekt", når der ikke træffes yderligere foranstaltninger. I det andet tilfælde optræder denne "gentageeffekt" ikke. Det er derfor i det 30 første tilfælde ønskeligt at foretage korrektionen af positioneringen, således at der bliver styret forbi forstyrrelsesstedet på pladen. Den lokale forud fastsættelige størrelse Δ D er derfor nødvendig, hvilket imidlertid ikke er påkrævet i det andet tilfælde.25 Sportab can occur both due to plate failure (scratches, soiling) and due to shock (against the appliance). In the first case, a "recoil" of the scanner would result in a "repeat effect" when no further action is taken. In the second case, this "repeat effect" does not occur. Therefore, in the first case, it is desirable to make the correction of the positioning so as to guide past the perturbation point on the plate. Therefore, the local predetermined size Δ D is necessary, which is not required in the second case.
35 Hvis korrekti onssystemet arbejder tilstrækkeligt hurtigt, og hvis forud fastsætningen Δ D ikke er valgt for stor, er forstyrrelsen næppe hørbar. For η > 1 lader sportab, som opstår ved et "fremad-spring", altså i aftastningsretning, af aftasteren, sig ikke detektere. En forstyrrende afbrydelse forbliver da hørbar. I dette35 If the correction system works fast enough and if the predetermined Δ D is not chosen too large, the disturbance is hardly audible. For η> 1, sports loss caused by a "forward jump", ie in the sensing direction, of the scanner does not detect. A disturbing interruption then remains audible. In this
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5 tilfælde sker nemlig følgende: Tælleren 5a bliver til at begynde med sat på "1". I denne tilstand fastholdes kredsløbet, indtil der forekommer en yderligere forstyrrelse. Der sker afgivelse af et "not-ok"-signal fra servosystemet 3. Da dataene i lagrene 7a og 7b 5 nu ikke stemmer overens med hinanden, bliver tælleren 5a sat på nul over "not-ok"-signalet fra komparatoren 6a. Derved bliver porten 9 gennemkoblet, dvs. frigivet, og i referencelageret 7b bliver de sidste data før forstyrrelsen indlagt. Kredsløbet befinder sig igen i udgangsstillingen (første modus).Five cases occur as follows: The counter 5a is initially set to "1". In this state, the circuit is maintained until further interference occurs. A "not-ok" signal is output from the servo system 3. Since the data in bearings 7a and 7b 5 now do not match, the counter 5a is set to zero over the "not-ok" signal from comparator 6a. Thereby the gate 9 is routed, ie. released, and in the reference memory 7b, the last data before the disturbance is entered. The circuit is again in the initial position (first mode).
10 15 20 25 30 35.10 15 20 25 30 35.
Claims (5)
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3514034 | 1985-04-18 | ||
| DE19853514034 DE3514034A1 (en) | 1985-04-18 | 1985-04-18 | AUTOMATIC CORRECTION SYSTEM FOR THE SERVO CIRCUIT OF A DEVICE WITH OPTICAL SCANNING OF A ROTATING INFORMATION CARRIER |
| PCT/EP1986/000224 WO1986006201A1 (en) | 1985-04-18 | 1986-04-17 | Automatic correction system for the servo-circuit of a device with optical scanning of a rotating information support |
| EP8600224 | 1986-04-17 |
Publications (4)
| Publication Number | Publication Date |
|---|---|
| DK614286A DK614286A (en) | 1986-12-18 |
| DK614286D0 DK614286D0 (en) | 1986-12-18 |
| DK166054B true DK166054B (en) | 1993-03-01 |
| DK166054C DK166054C (en) | 1993-07-12 |
Family
ID=6268492
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK614286A DK166054C (en) | 1985-04-18 | 1986-12-18 | AUTOMATIC CORRECTION SYSTEM FOR SERVICE CIRCUIT IN A DEVICE WITH OPTICAL DETECTION OF A ROTATING INFORMATION CARRIER |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0220251B1 (en) |
| JP (1) | JPH0792989B2 (en) |
| KR (1) | KR940002962B1 (en) |
| DE (2) | DE3514034A1 (en) |
| DK (1) | DK166054C (en) |
| HK (1) | HK148494A (en) |
| SG (1) | SG8892G (en) |
| WO (1) | WO1986006201A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02230515A (en) * | 1989-03-03 | 1990-09-12 | Sony Corp | Optical recording and reproducing device |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55113172A (en) * | 1979-02-19 | 1980-09-01 | Matsushita Electric Ind Co Ltd | Detection system for abnormal reproduction state |
| US4307418A (en) * | 1979-10-12 | 1981-12-22 | Rca Corporation | Video disc player system for correlating stylus position with information previously detected from disc |
| US4313134A (en) * | 1979-10-12 | 1982-01-26 | Rca Corporation | Track error correction system as for video disc player |
| JPS57104386A (en) * | 1980-12-19 | 1982-06-29 | Trio Kenwood Corp | Video disc playback device |
| US4488278A (en) * | 1982-08-17 | 1984-12-11 | Rca Corporation | Coding system for digital audio disc record |
| JPS5936385A (en) * | 1982-08-20 | 1984-02-28 | Matsushita Electric Ind Co Ltd | Reading circuit of track address |
| JPS59117762A (en) * | 1982-12-24 | 1984-07-07 | Nippon Columbia Co Ltd | Disc reproducing device |
| JPS59167879A (en) * | 1983-03-15 | 1984-09-21 | Toshiba Corp | Detector of track jump in disc record reproducing system |
| JPS59201274A (en) * | 1983-04-27 | 1984-11-14 | Sony Corp | Disk reproducing device |
| JPS607658A (en) * | 1983-06-24 | 1985-01-16 | Victor Co Of Japan Ltd | Method for correcting address of disc-like information recording medium |
| JPS6043270A (en) * | 1983-08-19 | 1985-03-07 | Sony Corp | Disk player |
| NL8303565A (en) * | 1983-10-17 | 1985-05-17 | Philips Nv | Apparatus for displaying information from a plate-shaped optically readable record carrier. |
-
1985
- 1985-04-18 DE DE19853514034 patent/DE3514034A1/en not_active Withdrawn
-
1986
- 1986-04-17 EP EP86902819A patent/EP0220251B1/en not_active Expired - Lifetime
- 1986-04-17 JP JP61502607A patent/JPH0792989B2/en not_active Expired - Lifetime
- 1986-04-17 DE DE8686902819T patent/DE3674534D1/en not_active Expired - Lifetime
- 1986-04-17 WO PCT/EP1986/000224 patent/WO1986006201A1/en active IP Right Grant
- 1986-12-18 DK DK614286A patent/DK166054C/en not_active IP Right Cessation
- 1986-12-18 KR KR8670904A patent/KR940002962B1/en not_active IP Right Cessation
-
1992
- 1992-01-31 SG SG88/92A patent/SG8892G/en unknown
-
1994
- 1994-12-30 HK HK148494A patent/HK148494A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| HK148494A (en) | 1995-01-06 |
| DK614286A (en) | 1986-12-18 |
| JPH0792989B2 (en) | 1995-10-09 |
| DE3514034A1 (en) | 1986-10-23 |
| DK166054C (en) | 1993-07-12 |
| DK614286D0 (en) | 1986-12-18 |
| KR880700407A (en) | 1988-03-15 |
| SG8892G (en) | 1992-03-20 |
| KR940002962B1 (en) | 1994-04-09 |
| WO1986006201A1 (en) | 1986-10-23 |
| DE3674534D1 (en) | 1990-10-31 |
| JPS62502002A (en) | 1987-08-06 |
| EP0220251A1 (en) | 1987-05-06 |
| EP0220251B1 (en) | 1990-09-26 |
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