Inventor · disambiguated record
Ronald Quan
Also filed as: QUAN RONALD
121 granted patents·28 pending applications·2,068 citations·filing 1980–2024
99Inventor score
Top patents by PatentIndex Score
149 records- 0197US4740675ADigital bar code slot reader with threshold comparison of the differentiated bar code signalHEWLETT PACKARD CO·Filed 1986·Granted Apr 26, 1988·186 cites·4 claims
- 0295US5194965AMethod and apparatus for disabling anti-copy protection system in video signalsMACROVISION CORP·Filed 1990·Granted Mar 16, 1993·107 cites·17 claims
- 0394US7492896B2Copy protection for video signal using added negative amplitude pulseMACROVISION CORP·Filed 2007·Granted Feb 17, 2009·13 cites·6 claims
- 0493US9549226B2Method and apparatus for reducing and restoring the effectiveness of a commercial skip systemROVI SOLUTIONS CORP·Filed 2015·Granted Jan 17, 2017·7 cites·20 claims
- 0592US4963756AFocused line identifier for a bar code readerHEWLETT PACKARD CO·Filed 1989·Granted Oct 16, 1990·122 cites·33 claims
- 0691US7298962B2Method and apparatus for reducing and restoring the effectiveness of a commercial skip systemMACROVISION CORP·Filed 2003·Granted Nov 20, 2007·31 cites·72 claims
- 0791US6826352B1Dynamic video copy protection systemMACROVISION CORP·Filed 2000·Granted Nov 30, 2004·47 cites·53 claims
- 0891US6501842B2Method and apparatus for modifying a video signal by back porch loweringMACROVISION CORP·Filed 2000·Granted Dec 31, 2002·26 cites·15 claims
- 0990US7706533B2Copy protection for video signal using narrowed horizontal synchronization signalsMACROVISION CORP·Filed 2007·Granted Apr 27, 2010·7 cites·10 claims
- 1090US7050698B1Method and apparatus for synthesizing or modifying a copy protection signal using a lowered signal level portionMACROVISION CORP·Filed 2000·Granted May 23, 2006·38 cites·42 claims
- 1189US10536756B2Method and apparatus for reducing and restoring the effectiveness of a commercial skip systemROVI SOLUTIONS CORP·Filed 2018·Granted Jan 14, 2020·3 cites·20 claims
- 1289US7352863B2Copy protection for video signal using narrowed horizontal synchronization signals and amplitude modulationMACROVISION CORP·Filed 2005·Granted Apr 1, 2008·6 cites·21 claims
- 1389US5583936AVideo copy protection process enhancement to introduce horizontal and vertical picture distortionsMACROVISION CORP·Filed 1993·Granted Dec 10, 1996·67 cites·92 claims
- 1488US7620178B2Copy protection for video signal added pulsesMACROVISION CORP·Filed 2007·Granted Nov 17, 2009·8 cites·7 claims
- 1588US7085380B2Method for modifying a copy protected video signal with a negative amplitude pulseMACROVISION CORP·Filed 2001·Granted Aug 1, 2006·18 cites·14 claims
- 1688US7039294B2Method and apparatus for modifying the effects of color burst modifications to a video signalMACROVISION CORP·Filed 2001·Granted May 2, 2006·27 cites·16 claims
- 1787US8299852B2Method and apparatus for a gain control circuit via a high frequency signalQUAN RONALD·Filed 2011·Granted Oct 30, 2012·11 cites·9 claims
- 1887US5748733AMethod and apparatus to reduce effects of certain copy protection purses within a video signalMACROVISION CORP·Filed 1996·Granted May 5, 1998·51 cites·23 claims
- 1987US5229735AWide frequency deviation voltage controlled crystal oscillator having plural parallel crystalsMACROVISION CORP·Filed 1992·Granted Jul 20, 1993·78 cites·57 claims
- 2085US10063194B1Low voltage tube circuitsQUAN RONALD·Filed 2017·Granted Aug 28, 2018·5 cites·20 claims
- 2185US8704533B2Method and apparatus to measure differential phase and frequency modulation distortions for audio equipmentQUAN RONALD·Filed 2010·Granted Apr 22, 2014·6 cites·15 claims
- 2285US8527268B2Method and apparatus for improving speech recognition and identifying video program material or contentQUAN RONALD·Filed 2010·Granted Sep 3, 2013·12 cites·6 claims
- 2385US5633927AVideo copy protection process enhancement to introduce horizontal and vertical picture distortionsMACROVISION CORP·Filed 1995·Granted May 27, 1997·45 cites·12 claims
- 2485US5157510AMethod and apparatus for disabling anti-copy protection system in video signals using pulse narrowingMACROVISION CORP·Filed 1990·Granted Oct 20, 1992·78 cites·19 claims
- 2585US4458213AConstant quiescent current, class AB amplifier output stageSONY CORP·Filed 1982·Granted Jul 3, 1984·26 cites·3 claims
- 2684US12107559B2Method and apparatus to evaluate audio equipment for dynamic distortions and or differential phase and or frequency modulation effectsQUAN RONALD·Filed 2022·Granted Oct 1, 2024·1 cites·17 claims
- 2784US7550977B2Method and apparatus to measure differential phase and frequency modulation distortions for audio equipmentQUAN RONALD·Filed 2006·Granted Jun 23, 2009·10 cites·20 claims
- 2884US7236683B2Method and apparatus for providing or enhancing copy protection by adding selected negative-going and positive-going pulses in a video signal HBIMACROVISION CORP·Filed 2001·Granted Jun 26, 2007·22 cites·48 claims
- 2984US5953417AMethod and apparatus for digitally removing or defeating effects of copy protection signals from a video signalMACROVISION CORP·Filed 1998·Granted Sep 14, 1999·60 cites·19 claims
- 3084US5784523AMethod and apparatus for defeating effects of color burst modifications to a video signalMACROVISION CORP·Filed 1997·Granted Jul 21, 1998·66 cites·62 claims
- 3183US9820065B2Method and apparatus to evaluate audio equipment for dynamic distortions and or differential phase and or frequency modulation effectsQUAN RONALD·Filed 2017·Granted Nov 14, 2017·4 cites·20 claims
- 3281US8094818B2Method to synthesize video copy protection signalsQUAN RONALD·Filed 2005·Granted Jan 10, 2012·5 cites·4 claims
- 3380US10411009B1Field effect transistor circuitsQUAN RONALD·Filed 2018·Granted Sep 10, 2019·3 cites·7 claims
- 3480US7100209B2Method to provide the generation of an incorrect or unreliable vertical/frame rate signalMACROVISION CORP·Filed 2005·Granted Aug 29, 2006·5 cites·2 claims
- 3579US6836549B1Method and apparatus for synthesizing and reducing the effects of video copy protection signalsMACROVISION CORP·Filed 1999·Granted Dec 28, 2004·56 cites·55 claims
- 3678US7907727B2System and method for allowing copying or distribution of a copy protected signalROVI SOLUTIONS CORP·Filed 2005·Granted Mar 15, 2011·4 cites·47 claims
- 3778US6091822AMethod and apparatus for recording scrambled video audio signals and playing back said video signal, descrambled, within a secure environmentMACROVISION CORP·Filed 1998·Granted Jul 18, 2000·63 cites·47 claims
- 3878US5625691AMethod and apparatus to defeat certain copy protection pulses within a video signalMACROVISION CORP·Filed 1995·Granted Apr 29, 1997·28 cites·4 claims
- 3977US7805056B2Methods and apparatus for providing cycles of normal and non normal phase in a color burst signalROVI SOLUTIONS CORP·Filed 2005·Granted Sep 28, 2010·3 cites·18 claims
- 4077US5504815AMethod and apparatus for scrambling and descramblingMACROVISION CORP·Filed 1995·Granted Apr 2, 1996·36 cites·6 claims
- 4176US8306403B2Content control via guide data and/or metadataQUAN RONALD·Filed 2010·Granted Nov 6, 2012·4 cites·26 claims
- 4276US6516132B1Method and apparatus for improving the effects of color burst modifications to a video signalMACROVISION CORP·Filed 1996·Granted Feb 4, 2003·49 cites·29 claims
- 4376US6327422B1Method and apparatus for modifying the effects of color burst modifications to a video signalMACROVISION CORP·Filed 1998·Granted Dec 4, 2001·35 cites·18 claims
- 4476US6285765B1Method and apparatus for reducing effects of copy protection of composite video signalMACROVISION CORP·Filed 1998·Granted Sep 4, 2001·26 cites·9 claims
- 4576US5159631AAudio scrambling system using in-band carrierMACROVISION CORP·Filed 1990·Granted Oct 27, 1992·51 cites·32 claims
- 4675US10651810B1Field effect transistor circuitsQUAN RONALD·Filed 2019·Granted May 12, 2020·2 cites·7 claims
- 4775US9386385B2Method and apparatus to evaluate audio equipment via filter banks for dynamic distortions and or differential phase and frequency modulation effectsQUAN RONALD·Filed 2014·Granted Jul 5, 2016·3 cites·19 claims
- 4875US4682015ALow powered high ambient light bar code reader circuitHEWLETT PACKARD CO·Filed 1985·Granted Jul 21, 1987·38 cites·8 claims
- 4974US11128262B2Low voltage tube circuitsQUAN RONALD·Filed 2018·Granted Sep 21, 2021·2 cites·21 claims
- 5074US9060182B2Method and apparatus for reducing and restoring the effectiveness of a commercial skip systemQUAN RONALD·Filed 2012·Granted Jun 16, 2015·1 cites·18 claims
Showing the top 50 of 149 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →