US 11,835,835 B2
Electro-optic media and writable display incorporating the same
Michael D. McCreary, Acton, MA (US); Richard J. Paolini, Jr., Framingham, MA (US); Stephen J. Telfer, Arlington, MA (US); and Samantha Morrill, Nashua, NH (US)
Assigned to E Ink Corporation, Billerica, MA (US)
Filed by E Ink Corporation, Billerica, MA (US)
Filed on Oct. 28, 2022, as Appl. No. 17/975,658.
Application 17/975,658 is a continuation of application No. 16/665,151, filed on Oct. 28, 2019, granted, now 11,513,413.
Claims priority of provisional application 62/752,614, filed on Oct. 30, 2018.
Prior Publication US 2023/0048575 A1, Feb. 16, 2023
Int. Cl. G06F 3/00 (2006.01); G02F 1/167 (2019.01); G06F 3/0354 (2013.01); B32B 17/10 (2006.01); G02F 1/00 (2006.01)
CPC G02F 1/167 (2013.01) [B32B 17/10522 (2013.01); G02F 1/0027 (2013.01); G06F 3/03545 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An electro-optic device in combination with a stylus, the stylus comprising a first tip and a second tip, a magnetic material being proximate to the first tip of the stylus, the second tip being non-magnetic and located on the opposite end of the stylus relative to the first tip, the electro-optic device comprising:
a first surface on a viewing side;
a second surface on the opposite side of the first surface;
an electrophoretic medium disposed between a light-transmissive electrically conductive layer and an array of pixel electrodes and comprising a plurality of particles in a fluid, the plurality of particles comprising:
a first type of particles having a first color, a first charge of a first charge polarity;
a second type of particles having a second color, a second charge of a second charge polarity; and
a third type of particles having a third color, a third charge of the second charge polarity;
wherein,
the first, second and third colors are different from one another;
the first charge polarity is opposite to the second charge polarity;
the plurality of particles are configured to migrate within the fluid in a direction responsive to an applied electric field;
the third type of particles are configured to migrate within the fluid in a direction responsive to an applied magnetic field gradient;
the second type of particles have an electric field threshold;
the second type of particles are not responsive to a magnetic field gradient;
such that:
(a) application of a voltage potential difference between the light-transmissive electrically conductive layer and a pixel electrode to generate an electric field stronger than the electric field threshold and having a polarity driving the first type of particles adjacent to the light-transmissive electrically conductive layer, will cause a pixel corresponding to the pixel electrode to display the first color at the first surface;
(b) once the first color is displayed at a first location of the first surface, contacting the first location with the first tip of the stylus once causes the third type of particles to migrate towards the first location; and
(c) once the third type of particles migrate towards the first location caused by the contacting of the magnetic tip of the stylus, contacting again the first location with the first tip of the stylus using a back-and-forth movement of the stylus, causes the second type of particles to migrate towards the first location.