US 11,656,526 B2
Switchable light-collimating layer including bistable electrophoretic fluid
Craig Lin, Fremont, CA (US); Xiaolong Zheng, Fremont, CA (US); Yih-Ming Kang, Fremont, CA (US); and HongMei Zang, Fremont, CA (US)
Assigned to E Ink California, LLC, Fremont, CA (US)
Filed by E INK CALIFORNIA, LLC, Fremont, CA (US)
Filed on Jun. 17, 2022, as Appl. No. 17/843,460.
Application 17/843,460 is a continuation of application No. 16/523,470, filed on Jul. 26, 2019, granted, now 11,397,366.
Claims priority of provisional application 62/717,124, filed on Aug. 10, 2018.
Prior Publication US 2022/0317541 A1, Oct. 6, 2022
Prior Publication US 2022/0317541 A1, Oct. 6, 2022
Int. Cl. G02F 1/167 (2019.01); G02F 1/29 (2006.01)
CPC G02F 1/29 (2013.01) 14 Claims
OG exemplary drawing
 
1. A method of fabrication of a switchable light-collimating film comprising the steps:
providing a first light-transmissive electrode layer;
depositing an embossing composition on the surface of the first light-transmissive electrode layer, creating a layer of embossing composition;
embossing the embossing composition at a temperature higher than the glass transition temperature of the layer of the embossing composition material, using a pre-patterned embossing tool, creating a patterned layer;
releasing the patterned layer from the embossing tool, creating a collimating layer having a plurality of elongate chambers, each elongated chamber having an opening, each elongated chamber having height, length (L), and width (W), the collimating layer having a thickness of at least 20 μm, the plurality of the elongated chambers being arranged in rows and columns when the collimating layer is viewed from above, the longer dimension of the elongated chambers running along rows, first row of elongated chambers including a gap between elongated chambers of first column and second column, second row of elongated chambers including a gap between elongated chambers of first column and second column, third row of elongated chambers including a gap between elongated chambers of first column and second column, the gap between elongated chambers of first column and second column in the first row being offset horizontally from the gap between elongated chambers of first column and second column in the second row, the gap between elongated chambers of first column and second column in the second row being offset horizontally from the gap between elongated chambers of first column and second column in the third row, the gap between elongated chambers of first column and second column in the first row being offset horizontally from the gap between elongated chambers of first column and second column in the third row,
filling each chamber of the plurality of the elongated chambers through their opening with a bistable electrophoretic fluid comprising pigment particles;
sealing the openings of the plurality of filled elongated chambers with a sealing composition, forming a sealing layer spanning the opening of each of the plurality of the elongated chambers;
laminating the sealed elongated chambers to a second light-transmissive electrode layer, wherein the first and second light-transmissive electrode layers are disposed on either side of the collimating layer.