DK171366B1 - Track or focussing control circuit for an optical recording and/or reproduction apparatus - Google Patents
Track or focussing control circuit for an optical recording and/or reproduction apparatus Download PDFInfo
- Publication number
- DK171366B1 DK171366B1 DK391488A DK391488A DK171366B1 DK 171366 B1 DK171366 B1 DK 171366B1 DK 391488 A DK391488 A DK 391488A DK 391488 A DK391488 A DK 391488A DK 171366 B1 DK171366 B1 DK 171366B1
- Authority
- DK
- Denmark
- Prior art keywords
- input
- control
- gain
- control circuit
- output
- Prior art date
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Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
- G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
-
- 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
- G11B7/0941—Methods and circuits for servo gain or phase compensation during operation
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
- G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
- G05B13/0205—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric not using a model or a simulator of the controlled system
- G05B13/024—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric not using a model or a simulator of the controlled system in which a parameter or coefficient is automatically adjusted to optimise the performance
- G05B13/025—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric not using a model or a simulator of the controlled system in which a parameter or coefficient is automatically adjusted to optimise the performance using a perturbation signal
-
- 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
- G11B7/0945—Methods for initialising servos, start-up sequences
-
- 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
- G11B7/0908—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 for focusing only
Landscapes
- Engineering & Computer Science (AREA)
- Software Systems (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Evolutionary Computation (AREA)
- Medical Informatics (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Optical Recording Or Reproduction (AREA)
- Control Of Amplification And Gain Control (AREA)
- Transmitters (AREA)
Abstract
Description
i DK 171366 B1in DK 171366 B1
Den foreliggende opfindelse angår en spor- eller fokusreguleringskreds til et optisk optegnings- og/eller gengiveapparat.The present invention relates to a track or focus control circuit for an optical recording and / or reproducing apparatus.
5 Reguleringskredse bliver f.eks. anvendt i CD-pladespillere for at føre den optiske aftastningsanordning på datasporet på CD-pladen og for at fokusere den aftastende lysstråle på pladeoverfladen. Disse servoreguleringskredse, sporreguleringskredsen og fokusreguleringskredsen skal arbejde præcist og være indstillet 10 nøjagtigt, for at en fejlfri lydgengivelse opnås.5 Control circuits will be e.g. used in CD recorders to guide the optical scanning device on the data track of the CD record and to focus the scanning light beam on the record surface. These servo control circuits, the track control circuit and the focus control circuit must work accurately and be set exactly 10 to achieve a flawless sound reproduction.
Indstillingen af forstærkningen ved reguleringskredsene sker i reglen manuelt ved indstilling af et potentiometer. Disse indstil-’'Tingsarbejder er relativt kostbare og kræver meget tid. Da de i 15 reguleringskredsene og den optiske aftastningsanordning indeholdte elektroniske komponenter endvidere ældes i tidens løb, skal forstærkningen hyppigt efterindstilles manuelt ved regulatorerne. Indstillingen manuelt såvel ved produktionen som ved vedligeholdelsen er naturligvis en ulempe, fordi den kræver tid og dermed også 20 koster penge.As a rule, the gain at the control circuits is set manually by setting a potentiometer. These settings - '' Things work is relatively expensive and requires a lot of time. Furthermore, as the electronic components contained in the 15 control circuits and the optical sensing device become older over time, the gain must be frequently reset manually by the controllers. Setting the manual manually during both production and maintenance is of course a disadvantage because it requires time and thus also 20 costs money.
Fra US-A 4.096.425 kendes en fremgangsmåde til automatisk indstilling af reguleringsforstærkningen i en reguleringskreds, hvor en måleimpuls skal indføres i reguleringskredsen. Ud fra en sammenlig-25 ning af den tilførte måleimpuls med det af denne bevirkede impulssvar bliver reguleringsforstærkningen afledet.US-A 4,096,425 discloses a method for automatically adjusting the control gain in a control circuit where a measuring pulse is to be introduced into the control circuit. From a comparison of the applied measurement pulse with the pulse response produced by this, the control gain is derived.
I US-A 3.727.035 er forklaret, hvorfor der f.eks. i en reguleringskreds, i hvis reguleringsproces der deltager en katalysator, fra tid 30 til anden påny skal beregnes parametrene for systemligningen, fordi virkningen af katalysatoren aftager i tidens løb. De til enhver tid aktuelle parametre for systemligningen bliver beregnet ud fra impulssvaret af et testimpulspar med forskellig polaritet, som tilføres reguleringskredsen.US-A 3,727,035 explains why, e.g. in a regulatory circuit, in whose control process a catalyst participates, from time 30 to time the parameters of the system equation must be recalculated because the effect of the catalyst decreases over time. The current equation parameters for the system equation are calculated from the pulse response of a test pulse pair of different polarity applied to the control circuit.
På grund af pladeslaget bliver indstillingen af forstærkningen i spor- og i fokusreguleringskredsen i et optisk optegnings- og/eller gengiveapparat imidlertid vanskeliggjort.However, due to the record stroke, the adjustment of the gain in the track and focus control circuitry in an optical recording and / or reproducing apparatus becomes difficult.
35 DK 171366 B1 235 DK 171366 B1 2
En spor- eller fokusreguleringskreds af den i krav l's indledning angivne art er ejendommelig ved det i samme kravs kendetegnende del angivne, nemlig ved at den anden indgang på komparatoren er forbundet med den ene pol på en referencespændingskilde, hvis anden pol 5 over en modstand er forbundet med den første indgang på det andet summationssted og over en kondensator lagt på referencepotential. Herved forbedres indstillingen af reguleringsforstærkningen af følgende grund. Modstanden og kondensatoren danner et lavpasfilter, som fører lavfrekvente ændringer af reguleringsstørrelsen, der 10 forårsages af pladeslaget, til den anden indgang på komparatoren. Referencestørrelsen på den anden indgang på komparatoren bliver derfor til stadighed indstillet efter de lavfrekvente ændringer af reguleringsstørrelsen, hvorved der opnås en mere nøjagtig indstilling af reguleringsforstærkningen.A track or focus control circuit of the type specified in the preamble of claim 1 is characterized by the characterizing part of the same claim, namely that the second input of the comparator is connected to one pole of a reference voltage source whose second pole 5 is over a resistor. connected to the first input at the second summation site and over a capacitor placed on reference potential. This improves the adjustment of the adjustment gain for the following reason. The resistor and capacitor form a low-pass filter, which transmits low-frequency changes in the control size caused by the plate stroke to the second input of the comparator. Therefore, the reference size of the second input of the comparator is constantly adjusted according to the low frequency changes of the control size, thereby obtaining a more accurate adjustment of the control gain.
1515
Opfindelsen skal herefter forklares nærmere under henvisning til tegningen, hvor fig. 1 viser et udførelseseksempel på reguleringskredsen 20 ifølge opfindelsen, fig. 2 forløbet af reguleringsstørrelsen i afhængighed af en måleimpuls.The invention will now be explained in more detail with reference to the drawing, in which fig. 1 shows an embodiment of the control circuit 20 according to the invention; FIG. 2 shows the magnitude of the control size depending on a measurement pulse.
Opfindelsen skal nu forklares ved hjælp af det i fig. 1 viste 25 udførelseseksempel og det i fig. 2 viste diagram.The invention will now be explained by means of the embodiment of FIG. 1, and the embodiment shown in FIG. 2.
I fig. 1 bliver styrestørrelsen W ført til den første indgang på et summationssted SI, hvis anden indgang er forbundet med udgangen på reguleringsstrækningen RS. Reguleringsstrækningen RS indeholder et 30 indstillingsled, en såkaldt aktuator A, og en som måleføler tjenende fotodetektor PH til optagelse af den aktuelle værdi. Udgangen på summationsstedet SI er forbundet med indgangen på en forforstærker V, hvis udgang umiddelbart er forbundet med den første indgang på et summationssted S2 og over et filter, f.eks. en som højpasfilter 35 tilvejebragt kondensator Cl, med den første indgang på en komparator VL. Den anden indgang på komparatoren VL er sluttet til en referencespændingskilde U. Udgangen på summationsstedet SI er forbundet med indgangen på regulatoren RG, som er udstyret med en reguleringsforstærker, og hvis udgang er forbundet med indgangen på DK 171366 Bl 3 reguleringsstrækningen RS. Udgangen på komparatoren VL, der f.eks. kan være udført som analog-digital omsætter, er forbundet med indgangen på en mikrodatamat MC, hvis første udgang er forbundet med den anden indgang på summationsstedet S2, og hvis anden udgang er 5 forbundet med indgangen til indstilling af reguleringsforstærkningen på regulatoren RG.In FIG. 1, the control size W is passed to the first input of a summation point S1, the second input of which is connected to the output of the control section RS. The control section RS contains a 30 setting link, a so-called actuator A, and a photodetector PH serving as a measuring sensor for recording the current value. The output of the summation point S1 is connected to the input of a preamplifier V, the output of which is directly connected to the first input of a summation point S2 and over a filter, e.g. capacitor C1, provided as a high pass filter 35, with the first input of a comparator VL. The second input of the comparator VL is connected to a reference voltage source U. The output of the summing point S1 is connected to the input of the controller RG, which is equipped with a control amplifier and whose output is connected to the input of DK 171366 B1 of the control line RS. The output of the comparator VL, e.g. may be designed as an analogue-digital converter, connected to the input of a microcomputer MC, the first output of which is connected to the second input of the summation location S2 and the second output of which is connected to the input of adjusting the gain of the controller RG.
Modstanden R og kondensatoren C2 danner et lavpasfilter, der lader lavfrekvente ændringer af reguleringsstørrelsen x, som hovedsagelig 10 forårsages af pladeslag, komme frem til den anden indgang på komparatoren VL. Da referencestørrelsen på den anden indgang på komparatoren VL derved til stadighed følger de lavfrekvente ændringer af reguleringsstørrelsen x, kan reguleringsforstærkningen 'indstilles mere nøjagtigt.The resistor R and capacitor C2 form a low-pass filter that allows low-frequency changes of the control size x, which are mainly caused by plate blows, to reach the second input of the comparator VL. As the reference size of the second input of the comparator VL thereby constantly follows the low frequency changes of the control size x, the control gain 'can be adjusted more precisely.
1515
Ved begyndelsen af det automatiske indstillingsforløb af reguleringsforstærkningen kan reguleringsforstærkningen først indstilles på en middelværdi. Derefter afgiver mikrodatamaten MC en måleimpuls 20 til indgangen på regulatoren RG, indtil komparatoren VL ved hjælp af et signal angiver overfor mikrodatamaten MC, at reguleringsstørrelsen x har antaget den forudgivne ønskede værdi. Det tidsmæssige forløb af reguleringsstørrelsen x på udgangen af forforstærkeren V i afhængighed af måleimpulsen er vist i fig. 2.At the beginning of the automatic adjustment cycle of the control gain, the control gain can first be set to a mean value. Then, the microcomputer MC outputs a measurement pulse 20 to the input of the controller RG until the comparator VL, by means of a signal, indicates to the microcomputer MC that the control size x has assumed the predetermined desired value. The temporal course of the control size x at the output of the preamp V depending on the measurement pulse is shown in FIG. 2nd
2525
Da den forudgivne ønskede værdi for reguleringsstørrelsen x er proportional med réguleringsforstærkningen, består der mellem varigheden af måleimpulsen og reguleringsforstærkningen en proportional sammenhæng. Mikrodatamaten MC konstaterer ud fra varigheden 30 af måleimpulsen, hvor stor reguleringsforstærkningen faktisk er og kan derfor indstille den på den korrekte værdi, såfremt den ikke tilfældigvis allerede var indstillet på den rigtige værdi.Since the predicted desired value for the control magnitude x is proportional to the control gain, there is a proportional relationship between the duration of the measurement pulse and the control gain. The microcomputer MC determines, based on the duration 30 of the measurement pulse, the magnitude of the control gain, and can therefore set it to the correct value, if it did not happen to be already set to the correct value.
Denne fremgangsmåde kan f.eks. gentages flere gange for at tilveje-35 bringe flere værdier for indstillingen af reguleringsforstærkningen, af hvilke der dannes en middelværdi, der anses som endelig værdi.This method can e.g. is repeated several times to provide 35 values for setting the control gain, of which a mean value is considered to be the final value.
Ved dannelsen af middelværdien kan sådanne værdier, som ligger udenfor et forud fastsætteligt område lades ude af betragtning.In the formation of the mean, such values which are outside a predetermined range can be disregarded.
4 DK 171366 B14 DK 171366 B1
Det er særlig fordelagtigt efter måleimpulsen at tilvejebringe en impuls med modsat polaritet, fordi reguleringskredsens indsvingning derved sker væsentligt hurtigere under stærk dæmpning af oversvingene. Denne fremgangsmåde kan gentages flere gange for at kunne 5 danne en middelværdi.It is particularly advantageous after the measurement pulse to provide a pulse of opposite polarity, because the oscillation of the control circuit is thereby considerably faster during strong damping of the oscillations. This procedure can be repeated several times to form an average.
Mikrodatamaten MC kan eksempelvis afgive flere måleimpulser med konstant amplitude og konstant varighed efter hinanden til regulatoren RG og samtidigt foreger reguleringsforstærkningen trinvis fra 10 måleimpuls til måleimpuls, indtil komparatoren VL ved hjælp af et signal angiver overfor mikrodatamaten MC, at reguleringsstørrelsen x har antaget den forudgivne ønskede værdi.For example, the microcomputer MC can output several measuring pulses of constant amplitude and constant duration one after the other to the controller RG, and at the same time, the control gain increments incrementally from 10 measuring pulses to measuring pulses until the comparator VL indicates by means of a signal to the microcomputer MC that the control size x has assumed the predicted desired value.
Også denne fremgangsmåde kan gentages flere gange. Ud fra de ved 15 gentagelserne tilvejebragte værdier for reguleringsforstærkningen dannes en middelværdi, som reguleringsforstærkningen til slut indstilles på. Værdier, der ligger udenfor et forud fastsætteligt område, kan ved dannelsen af middelværdien lades ude af betragtning.This process can also be repeated several times. From the values obtained for the 15 repetitions at the 15 repetitions, a mean value is formed, at which the final gain is adjusted. Values outside a predetermined range can be neglected in the formation of the mean.
20 Det er også muligt til at begynde med at tilføre reguleringskredsen en første måleimpuls, indtil reguleringsstørrelsen x antager en første forud fastsættelig ønsket værdi. Derefter bliver en anden måleimpuls med modsat polaritet ført til reguleringskredsen, indtil reguleringsstørrelsen x antager en anden forud fastsættelig ønsket 25 værdi. Ud fra varigheden af den første og anden måleimpuls afledes kriteriet for indstillingen af reguleringsforstærkningen, idet denne fremgangsmåde ligeledes gentages flere gange for at danne en middelværdi .20 It is also possible to initially apply a first measuring pulse to the control circuit until the control size x assumes a first predetermined desired value. Then another measuring pulse of opposite polarity is fed to the control circuit until the control size x assumes another preset desired value. Based on the duration of the first and second measurement pulses, the criterion for setting the control gain is derived, as this method is also repeated several times to generate a mean.
30 Ved en yderligere udførelsesform for opfindelsen bliver der til reguleringskredsen ført måleimpulser med konstant amplitude og konstant varighed, men modsat polaritet, og samtidig bliver reguleringsforstærkningen ændret trinvis fra måleimpuls til måleimpuls, indtil reguleringsstørrelelsen x antager en forud fastsættelig 35 første ønsket værdi og en forud fastsættelig anden ønsket værdi. Også denne fremgangsmåde kan gentages flere gange for at danne middel værdin.In a further embodiment of the invention, measuring pulses of constant amplitude and constant duration, but opposite of polarity, are fed to the control circuit, and at the same time the control gain is changed stepwise from measuring pulse to measuring pulse until the control size x assumes a predetermined first desired value and a predetermined other desired value. Also, this process can be repeated several times to form the mean value.
Måleimpulserne kan f.eks. hver gang ved indkoblingen af CD- 5 DK 171366 B1 pladespilleren afgives af mikrodatamaten MC for at indstille reguleringsforstærkningen. Også under pauserne mellem to på en CD-plade lagrede musikstykker og endog under musikgengivelsen kan reguleringsforstærkningen indstilles, uden at apparatets gengivelse derved 5 forringes hørbart.The measuring pulses can e.g. each time the CD player is switched on by the microcomputer MC to set the control gain. Also during breaks between two pieces of music stored on a CD, and even during music playback, the adjustable gain can be adjusted, without thereby reducing the reproduction of the apparatus audibly.
Derfor bortfalder ikke kun de besværlige og tidsrøvende manuelle indstillingsarbejder ved produktionen, men også senere nyindstillinger, der skal udføres manuelt, bliver overflødige, fordi 10 ældningen af komponenterne, som er indeholdt i reguleringskredsen, og driften af deres parametre som følge af temperaturvariationer, ikke mere spiller nogen rolle. Desuden er indstillingen mere nøjagtig end ved den indledningsvis nævnte kendte teknik.Therefore, not only the cumbersome and time-consuming manual tuning work in production, but also later new adjustments to be performed manually, become obsolete because the aging of the components contained in the control circuit and the operation of their parameters due to temperature variations no longer cease. does not matter. In addition, the setting is more accurate than the prior art mentioned.
* % ^ 15 20 25 1 35*% ^ 15 20 25 1 35
Claims (3)
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3638831 | 1986-11-13 | ||
| DE19863638831 DE3638831A1 (en) | 1986-11-13 | 1986-11-13 | METHOD AND CIRCUIT FOR THE AUTOMATIC SETTING OF THE CONTROL AMPLIFICATION IN A CONTROL CIRCUIT |
| EP8700697 | 1987-11-12 | ||
| PCT/EP1987/000697 WO1988003671A1 (en) | 1986-11-13 | 1987-11-12 | Process and circuit for automatic setting of the gain in a control circuit |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DK391488A DK391488A (en) | 1988-07-13 |
| DK391488D0 DK391488D0 (en) | 1988-07-13 |
| DK171366B1 true DK171366B1 (en) | 1996-09-23 |
Family
ID=6313898
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK391488A DK171366B1 (en) | 1986-11-13 | 1988-07-13 | Track or focussing control circuit for an optical recording and/or reproduction apparatus |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0290524B1 (en) |
| JP (1) | JP2956765B2 (en) |
| KR (1) | KR950015161B1 (en) |
| AT (1) | ATE71749T1 (en) |
| DE (2) | DE3638831A1 (en) |
| DK (1) | DK171366B1 (en) |
| HK (1) | HK16596A (en) |
| WO (1) | WO1988003671A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5319539A (en) * | 1992-05-27 | 1994-06-07 | The Foxboro Company | Method and apparatus for generating an optimal gain of process control equipment |
| US5367513A (en) * | 1993-11-05 | 1994-11-22 | International Business Machines Corporation | Focus and tracking servo decoupling system |
| DE19757440A1 (en) * | 1997-12-23 | 1999-06-24 | Thomson Brandt Gmbh | Automated setting of the gain in control loops |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3727035A (en) * | 1971-06-03 | 1973-04-10 | Phillips Petroleum Co | Pulse test of digital control system |
| US4096425A (en) * | 1974-09-19 | 1978-06-20 | Ferranti Limited | Servo systems |
| US4466087A (en) * | 1981-01-08 | 1984-08-14 | Xerox Corporation | Optical memory system for a reading/writing, verifying and tracking module |
| JPS6148162A (en) * | 1984-08-14 | 1986-03-08 | Sony Corp | Disc loading device |
| JPS61208102A (en) * | 1985-03-13 | 1986-09-16 | Mitsubishi Electric Corp | Automatic tuning controller |
| JPS61226803A (en) * | 1985-03-30 | 1986-10-08 | Toshiba Corp | Process control device |
-
1986
- 1986-11-13 DE DE19863638831 patent/DE3638831A1/en not_active Withdrawn
-
1987
- 1987-11-12 JP JP62506775A patent/JP2956765B2/en not_active Expired - Lifetime
- 1987-11-12 DE DE8787907425T patent/DE3776140D1/en not_active Expired - Lifetime
- 1987-11-12 WO PCT/EP1987/000697 patent/WO1988003671A1/en active IP Right Grant
- 1987-11-12 AT AT87907425T patent/ATE71749T1/en not_active IP Right Cessation
- 1987-11-12 EP EP87907425A patent/EP0290524B1/en not_active Expired - Lifetime
- 1987-11-12 KR KR1019880700817A patent/KR950015161B1/en not_active IP Right Cessation
-
1988
- 1988-07-13 DK DK391488A patent/DK171366B1/en not_active IP Right Cessation
-
1996
- 1996-01-25 HK HK16596A patent/HK16596A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01501349A (en) | 1989-05-11 |
| JP2956765B2 (en) | 1999-10-04 |
| DE3776140D1 (en) | 1992-02-27 |
| EP0290524B1 (en) | 1992-01-15 |
| HK16596A (en) | 1996-02-02 |
| DK391488A (en) | 1988-07-13 |
| WO1988003671A1 (en) | 1988-05-19 |
| DE3638831A1 (en) | 1988-05-19 |
| KR890700239A (en) | 1989-03-10 |
| DK391488D0 (en) | 1988-07-13 |
| KR950015161B1 (en) | 1995-12-23 |
| EP0290524A1 (en) | 1988-11-17 |
| ATE71749T1 (en) | 1992-02-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| B1 | Patent granted (law 1993) | ||
| PUP | Patent expired |