US 12,361,902 B2
Driving voltages for advanced color electrophoretic displays and displays with improved driving voltages
Stephen J. Telfer, Arlington, MA (US); Kosta Ladavac, Cambridge, MA (US); and Christopher L. Hoogeboom, Burlington, MA (US)
Assigned to E Ink Corporation, Billerica, MA (US)
Filed by E INK CORPORATION, Billerica, MA (US)
Filed on Feb. 28, 2024, as Appl. No. 18/589,543.
Application 18/100,848 is a division of application No. 17/474,375, filed on Sep. 14, 2021, granted, now 11,776,496, issued on Oct. 3, 2023.
Application 18/589,543 is a continuation of application No. 18/100,848, filed on Jan. 24, 2023, granted, now 11,948,523.
Claims priority of provisional application 63/078,829, filed on Sep. 15, 2020.
Prior Publication US 2024/0203373 A1, Jun. 20, 2024
Int. Cl. G09G 3/34 (2006.01); G02F 1/167 (2019.01)
CPC G09G 3/344 (2013.01) [G02F 1/167 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A color electrophoretic display comprising:
a controller;
a light-transmissive electrode at a viewing surface;
a backplane including an array of thin film transistors coupled to pixel electrodes, each thin film transistor comprising a layer of a metal oxide semiconductor; and
a four-particle color electrophoretic medium disposed between the light-transmissive electrode and the backplane, the four-particle color electrophoretic medium comprising:
(a) a fluid;
(b) a plurality of first and a plurality of second particles dispersed in the fluid, the first and second particles bearing charges of opposite polarity, the first particle being a light-scattering particle and the second particle having one of the subtractive primary colors; and
(c) a plurality of third and a plurality of fourth particles dispersed in the fluid, the third and fourth particles bearing charges of opposite polarity, the third and fourth particles each having a subtractive primary color different from each other and from the second particles,
wherein the controller is configured to provide driving voltages at five or more different voltage levels including voltages greater than 25 Volts and less than −25 Volts to the pixel electrodes while holding the light-transmissive electrode at constant voltage to enable color optical state switching of pixels of the four-particle color electrophoretic medium among a plurality of primary colors.