Duane W. Marhefka

Person

Winona, OH, US

People

Patents Grantslast 30 patents

Information Patent Grant
Writing device including cholesteric liquid crystal and having sect...
- Patent number 11,609,470
- Issue date Mar 21, 2023
- Kent Displays, Inc.
- Todd Ernst
- G02 - OPTICS
Information Patent Grant
Liquid crystal eWriter system with resistive digitizer and having m...
- Patent number 10,649,261
- Issue date May 12, 2020
- Kent Displays Inc.
- Mark Lightfoot
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Selectively erasable eWriter with user adjustment
- Patent number 10,634,939
- Issue date Apr 28, 2020
- Kent Displays Inc.
- Duane Marhefka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Liquid crystal writing device with slow discharge erase
- Patent number 10,558,065
- Issue date Feb 11, 2020
- Kent Displays Inc.
- Duane Marhefka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Writing tablet information recording device
- Patent number 9,134,561
- Issue date Sep 15, 2015
- Kent Displays Incorporated
- Duane W. Marhefka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Electronic skin having uniform gray scale reflectivity
- Patent number 8,502,763
- Issue date Aug 6, 2013
- Manning Ventures, Inc.
- Duane W. Marhefka
- G02 - OPTICS
Information Patent Grant
Video rate ChLCD driving with active matrix backplanes
- Patent number 8,436,847
- Issue date May 7, 2013
- Kent Displays Incorporated
- Duane Marhefka
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Grant
Electronic skin having uniform gray scale reflectivity
- Patent number 8,310,630
- Issue date Nov 13, 2012
- Manning Ventures, Inc.
- Duane W. Marhefka
- G02 - OPTICS
Information Patent Grant
Power management method and device for low-power displays
- Patent number 7,675,239
- Issue date Mar 9, 2010
- Kent Displays Incorporated
- Duane Marhefka
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Grant
Display device with electrical zipper interconnect
- Patent number 7,479,940
- Issue date Jan 20, 2009
- Kent Displays Incorporated
- Duane W. Marhefka
- H05 - ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR

Patents Applicationslast 30 patents

Information Patent Application
LIQUID CRYSTAL WRITING DEVICE WITH SLOW DISCHARGE ERASE
- Publication number 20190317348
- Publication date Oct 17, 2019
- KENT DISPLAYS INC.
- Duane MARHEFKA
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Application
SELECTIVELY ERASABLE EWRITER WITH USER ADJUSTMENT
- Publication number 20190056611
- Publication date Feb 21, 2019
- KENT DISPLAYS INC.
- Duane MARHEFKA
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Application
LIQUID CRYSTAL EWRITER SYSTEM WITH RESISTIVE DIGITIZER AND HAVING M...
- Publication number 20180031886
- Publication date Feb 1, 2018
- KENT DISPLAYS INC.
- Mark LIGHTFOOT
- G02 - OPTICS
Information Patent Application
WRITING TABLET INFORMATION RECORDING DEVICE
- Publication number 20140043547
- Publication date Feb 13, 2014
- Kent Displays Incorporated
- Duane W. Marhefka
- G02 - OPTICS
Information Patent Application
Cholesteric Liquid Crystal Writing Tablet Erased By A Piezoelectric...
- Publication number 20130342432
- Publication date Dec 26, 2013
- Kent Displays Incorporated
- Tod Schneider
- G02 - OPTICS
Information Patent Application
WRITING TABLET INFORMATION RECORDING DEVICE
- Publication number 20130107144
- Publication date May 2, 2013
- Kent Displays Incorporated
- Duane Marhefka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Application
WRITING TABLET INFORMATION RECORDING DEVICE
- Publication number 20120268420
- Publication date Oct 25, 2012
- Duane Marhefka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Application
ELECTRONIC SKIN HAVING UNIFORM GRAY SCALE REFLECTIVITY
- Publication number 20120086735
- Publication date Apr 12, 2012
- Kent Displays Incorporated
- Duane W. MARHEFKA
- G02 - OPTICS
Information Patent Application
VIDEO RATE ChLCD DRIVING WITH ACTIVE MATRIX BACKPLANES
- Publication number 20110128265
- Publication date Jun 2, 2011
- Kent Displays Incorporated
- Duane Marhefka
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Application
Electronic skin having uniform gray scale reflectivity
- Publication number 20090284691
- Publication date Nov 19, 2009
- Duane W. Marhefka
- G02 - OPTICS
Information Patent Application
POWER MANAGEMENT METHOD AND DEVICE FOR LOW-POWER DISPLAYS
- Publication number 20080037306
- Publication date Feb 14, 2008
- Kent Displays Incorporated
- Duane Marhefka
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Application
METHOD AND APPARATUS FOR DRIVING BISTABLE LIQUID CRYSTAL DISPLAY
- Publication number 20070279350
- Publication date Dec 6, 2007
- Kent Displays Incorporated
- Xiao-Yang Huang
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Application
Display device with electrical zipper interconnect
- Publication number 20060103641
- Publication date May 18, 2006
- Kent Displays Incorporated
- Duane W. Marhefka
- G02 - OPTICS

Duane W. Marhefka

Person

Patents Grantslast 30 patents

Writing device including cholesteric liquid crystal and having sect...

Liquid crystal eWriter system with resistive digitizer and having m...

Selectively erasable eWriter with user adjustment

Liquid crystal writing device with slow discharge erase

Writing tablet information recording device

Electronic skin having uniform gray scale reflectivity

Video rate ChLCD driving with active matrix backplanes

Electronic skin having uniform gray scale reflectivity

Power management method and device for low-power displays

Display device with electrical zipper interconnect

Patents Applicationslast 30 patents

LIQUID CRYSTAL WRITING DEVICE WITH SLOW DISCHARGE ERASE

SELECTIVELY ERASABLE EWRITER WITH USER ADJUSTMENT

LIQUID CRYSTAL EWRITER SYSTEM WITH RESISTIVE DIGITIZER AND HAVING M...

WRITING TABLET INFORMATION RECORDING DEVICE

Cholesteric Liquid Crystal Writing Tablet Erased By A Piezoelectric...

WRITING TABLET INFORMATION RECORDING DEVICE

WRITING TABLET INFORMATION RECORDING DEVICE

ELECTRONIC SKIN HAVING UNIFORM GRAY SCALE REFLECTIVITY

VIDEO RATE ChLCD DRIVING WITH ACTIVE MATRIX BACKPLANES

Electronic skin having uniform gray scale reflectivity

POWER MANAGEMENT METHOD AND DEVICE FOR LOW-POWER DISPLAYS

METHOD AND APPARATUS FOR DRIVING BISTABLE LIQUID CRYSTAL DISPLAY

Display device with electrical zipper interconnect