Inventor · disambiguated record
Alan A. Fennema
Also filed as: FENNEMA ALAN · FENNEMA ALAN A · FENNEMA ALAN AUGUST
35 granted patents·1 pending application·772 citations·filing 1984–2022
98Inventor score
Top patents by PatentIndex Score
36 records- 0193US6785075B2Self-writing servo and clock fields on a recording mediumSEAGATE TECHNOLOGY LLC·Filed 2001·Granted Aug 31, 2004·41 cites·17 claims
- 0293US5136569AOptical disk recorder for diverse media types and having a predetermined initialization or start-up procedureIBM·Filed 1990·Granted Aug 4, 1992·70 cites·13 claims
- 0392US5038333APositioning systems including reliable track crossing detection for high speed relative motionsIBM·Filed 1989·Granted Aug 6, 1991·59 cites·15 claims
- 0491US5499231AOptical disk drive with multiple data layer disk and system for focusing the optical beamIBM·Filed 1994·Granted Mar 12, 1996·56 cites·23 claims
- 0591US5060210AControlling head seeking speed in disk storage units by limiting displacement of head with respect to its supporting headarmIBM·Filed 1990·Granted Oct 22, 1991·57 cites·10 claims
- 0690US6771443B2Circumferential positioning of servo sectors for servo track writingSEAGATE TECHNOLOGY LLC·Filed 2001·Granted Aug 3, 2004·30 cites·25 claims
- 0787US12231832B2Method for pre-calculating and applying optimized phase patterns to LCoS switch panel of WSS moduleII VI DELAWARE INC·Filed 2022·Granted Feb 18, 2025·2 cites·25 claims
- 0887US4839876ATrack seeking using a track following loopIBM·Filed 1987·Granted Jun 13, 1989·35 cites·11 claims
- 0985US10505656B2Optical wavelength selective switches with guard bandsNOKIA SOLUTIONS & NETWORKS OY·Filed 2018·Granted Dec 10, 2019·2 cites·16 claims
- 1084US5138594AReducing amplitude variations of optical disk readback signals and increasing reliability of track-crossing countsIBM·Filed 1990·Granted Aug 11, 1992·42 cites·9 claims
- 1183US6898038B1Method and apparatus for disc drive data security using fields in servo wedgesSEAGATE TECHNOLOGY LLC·Filed 2001·Granted May 24, 2005·15 cites·25 claims
- 1283US5426625AMasking of tracking error signal abnormalities due to media defectsIBM·Filed 1994·Granted Jun 20, 1995·36 cites·7 claims
- 1382US6912235B2Apparatus and method for phase control of tunable external cavity lasersIOLON INC·Filed 2002·Granted Jun 28, 2005·19 cites·37 claims
- 1482US5220546AOperating optical disk drives including calibrating a tracking error signalIBM·Filed 1990·Granted Jun 15, 1993·35 cites·6 claims
- 1581US5134602ACalibrating optical disk recorders to some parameters during disk spin up while deferring calibration of other parametersIBM·Filed 1990·Granted Jul 28, 1992·32 cites·21 claims
- 1678US5164932AAcquiring a best focus using a focus signal offsetIBM·Filed 1990·Granted Nov 17, 1992·32 cites·8 claims
- 1777US5090002APositioning systems employing velocity and position control loops with position control loop having an extended rangeIBM·Filed 1989·Granted Feb 18, 1992·22 cites·59 claims
- 1874US6345021B1System and method of efficient servo sector encodingSEAGATE TECHNOLOGY·Filed 1998·Granted Feb 5, 2002·24 cites·38 claims
- 1974US4519553AMultiple spindle winding apparatusIBM·Filed 1984·Granted May 28, 1985·20 cites·10 claims
- 2073US6898221B2Apparatus for frequency tuning and locking and method for operating sameIOLON INC·Filed 2002·Granted May 24, 2005·16 cites·44 claims
- 2169US5425013ARelative position sensing calibration for optical storage deviceIBM·Filed 1993·Granted Jun 13, 1995·18 cites·4 claims
- 2269US4998233AAcquiring focus in optical systems using a focus error signal and a laser drive signalIBM·Filed 1988·Granted Mar 5, 1991·19 cites·20 claims
- 2368US5046060AServo error controlsIBM·Filed 1990·Granted Sep 3, 1991·18 cites·9 claims
- 2466US5768228AMethod and sytem for cancelling optical servo crosstalk in optical disk drivesIBM·Filed 1996·Granted Jun 16, 1998·18 cites·10 claims
- 2565US5142516AAnti-skating control of a positioning servo systemIBM·Filed 1990·Granted Aug 25, 1992·16 cites·15 claims
- 2657US7518816B2Method and apparatus for disc drive data security using fields in servo wedgesSEAGATE TECHNOLOGY LLC·Filed 2004·Granted Apr 14, 2009·2 cites·21 claims
- 2748US8032004B2Multimedia presentation formatVMEDIA RES INC·Filed 2007·Granted Oct 4, 2011·0 cites·1 claims
- 2848US5936919ASystem for compensating for hard sector noise degradation of tracking error signals in an optical data storage systemIBM·Filed 1997·Granted Aug 10, 1999·6 cites·16 claims
- 2947US5097361AControlling position of a rotatable transducer in devices employing such transducersIBM·Filed 1990·Granted Mar 17, 1992·7 cites·22 claims
- 3045US5974019AOptical system for two-dimensional positioning of light beamsSEAGATE TECHNOLOGY·Filed 1998·Granted Oct 26, 1999·6 cites·18 claims
- 3145US5257251ASingle loop servo-positioning systems having means for changing the dynamic range of a position-error signal with speed of the relatively movable membersIBM·Filed 1991·Granted Oct 26, 1993·9 cites·11 claims
- 3239US2004213306A1Apparatus and method for phase control of tunable external cavity lasersFiled 2004·Application pending·0 cites
- 3338US5233585AAcquiring focus in an optical disk system using a time and shape modified focus error signalIBM·Filed 1991·Granted Aug 3, 1993·4 cites·12 claims
- 3436US5128913AAcquiring focus in an optical system using a soft focus acquiring systemIBM·Filed 1990·Granted Jul 7, 1992·3 cites·12 claims
- 3532US6052345ASystem for compensating for hard sector noise degradation of tracking error signals in an optical data storage systemIBM·Filed 1999·Granted Apr 18, 2000·0 cites·18 claims
- 3626US5289319AApparatus and method for detecting physical orientation of a position system and for calibrating an optimum control for the system that is usable in optical disk recordersIBM·Filed 1992·Granted Feb 22, 1994·1 cites·15 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →