US 12,249,262 B2
Methods for measuring electrical properties of electro-optic displays
Karl Raymond Amundson, Cambridge, MA (US); Teck Ping Sim, Acton, MA (US); Michael D. McCreary, Acton, MA (US); and Yi Lu, Needham, MA (US)
Assigned to E Ink Corporation, Billerica, MA (US)
Filed by E INK CORPORATION, Billerica, MA (US)
Filed on Jun. 30, 2023, as Appl. No. 18/345,523.
Application 18/345,523 is a continuation of application No. 18/146,608, filed on Dec. 27, 2022, granted, now 11,854,448.
Claims priority of provisional application 63/301,747, filed on Jan. 21, 2022.
Claims priority of provisional application 63/293,947, filed on Dec. 27, 2021.
Prior Publication US 2023/0343260 A1, Oct. 26, 2023
Int. Cl. G09G 3/00 (2006.01); G01R 27/16 (2006.01); G09G 3/20 (2006.01); G09G 3/34 (2006.01)
CPC G09G 3/006 (2013.01) [G01R 27/16 (2013.01); G09G 3/2007 (2013.01); G09G 3/344 (2013.01); G09G 2310/06 (2013.01); G09G 2320/0257 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for driving an electro-optic display comprising a layer of electro-optic material disposed between a common electrode and a backplane, the backplane including an array of pixel electrodes, wherein each pixel electrode is coupled to a pixel transistor, wherein a display controller circuit applies waveforms to the array of pixel electrodes by applying one or more time-dependent voltages between the common electrode and the array of pixel electrodes via the pixel transistors, the method for driving comprising:
applying first measurement waveforms comprising one or more frames to a first portion of pixel electrodes of the array of pixel electrodes, wherein during each frame of the first measurement waveforms the same time-dependent voltages are applied to each pixel electrode of the first portion of pixel electrodes;
measuring a first current flowing through a current measurement circuit coupled between the common electrode and an output of the display controller circuit that applies time-dependent voltages to the common electrode;
determining a first impedance of the electro-optic material in proximity to the first portion of pixel electrodes based on the first current flowing through the current measurement circuit and the time-dependent voltages applied to each pixel electrode of the first portion of pixel electrodes during the first measurement waveforms;
selecting first driving waveforms to apply to each pixel electrode of the first portion of pixel electrodes based on the first impedance of the electro-optic material in proximity to the first portion of pixel electrodes; and
applying the first driving waveforms to the first portion of pixel electrodes, wherein the first driving waveforms comprise time-dependent voltages sufficient to change an optical state of the electro-optic display in proximity to the first portion of pixel electrodes.