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US 12,717,201 B2Granted
Variable light transmission device comprising electrophoretic medium having light reflective pigment particles
AssigneeE Ink Corporation
InventorsYu Xia, Dirk Hertel, Dan Luo, Stephen J. Telfer
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Abstract
A variable light transmission device is disclosed and a method of manufacture of the same. The variable light transmission device comprises two light transmissive electrodes and a microcell layer having a plurality of microcells, each microcell comprising a protrusion structure and a channel, and including an electrophoretic medium. The opacity of the device is controlled by an applied electric field.
Claims20
A variable light transmission device comprising:
- a first light transmissive electrode layer (202);
- a second light transmissive electrode layer (207);
- and
- a microcell layer (203), the microcell layer (203) being disposed between the first light transmissive electrode layer (202) and the second light transmissive electrode layer (207), the microcell layer (203) comprising a plurality of microcells (204) and a sealing layer (206),
- each microcell of the plurality of microcells (204) including an electrophoretic medium (209), the electrophoretic medium (209) comprising electrically charged pigment particles and a charge control agent, in a non-polar liquid,
- each microcell of the plurality of microcells (204) having a microcell opening (205), the sealing layer (206) spanning the microcell openings (205) of the plurality of microcells (204),
- each microcell of the plurality of microcells (204) comprising a microcell bottom layer (210), a protrusion structure (217), microcell walls (212), and a channel (215),
- the microcell bottom layer (210) having a microcell bottom inside surface (211), the microcell bottom inside surface (211) comprising an exposed microcell bottom inside surface (211a) and an unexposed microcell bottom inside surface (211b),
- each microcell of the plurality of microcells (204) comprising a first light blocking layer (232), the first light blocking layer (232) being in contact with the exposed microcell bottom inside surface (211a) and with the electrophoretic medium (209),
- the protrusion structure (217) having a protrusion base (218), a protrusion surface (221), a protrusion apex (219), and a protrusion height (220), the protrusion apex (219) having shorter distance from the microcell opening (205) than all other points of the protrusion structure (217), the protrusion height (220) being the distance between the protrusion base (218) and the protrusion apex (219), the protrusion surface (221) being the surface of the protrusion structure (217) not including the protrusion apex that is in contact with the electrophoretic medium (209),
- the microcell walls (212) having a microcell inside wall surface (213) and a microcell wall upper surface (214), the microcell inside wall surface (213) being the surface of the microcell walls (212) of a microcell that is in contact with the electrophoretic medium (209), the microcell wall upper surface (214) being the surface of the microcell walls (212) of a microcell that is in contact with the sealing layer (206),
- the channel (215) having a channel height (216), the channel height (216) being 50% of the protrusion height (220),
- the unexposed microcell bottom inside surface (211b) being in contact with the protrusion base (218),
- the channel (215) being a volume between the first light blocking layer (232), the protrusion surface (221), and the microcell inside wall surface (213).
11 more elements
A method of manufacture of a variable light transmission device comprising the steps:
- providing an assembly comprising a third electrode layer, a second light transmissive electrode layer, a layer comprising a plurality of microcells, the layer comprising a plurality of microcells being disposed between the third electrode layer and the second light transmissive electrode layer, each microcell of the plurality of microcells including a light blocking composition comprising (i) light absorbing electrically charged pigment particles, (ii) a polymer, oligomer, or monomer and, (iii) a solvent, each microcell of the plurality of microcells having a microcell opening, the third electrode layer spanning the microcell openings of the plurality of microcells, each microcell of the plurality of microcells comprising a microcell bottom layer, a protrusion structure, microcell walls, and a channel, the microcell bottom layer having a microcell bottom inside surface, the microcell bottom inside surface comprising an exposed microcell bottom inside surface and an unexposed microcell bottom inside surface;
- applying an electric field between the third electrode layer and the second light transmissive electrode layer via a waveform that causes movement of the light absorbing electrically charged pigment particles of the light blocking composition towards the channel and resulting in a state in which state the light absorbing electrically charged pigment particles are located inside the channel;
- curing the light blocking composition to form a light blocking layer on the exposed microcell bottom inside surface;
- removing the third electrode layer;
- filling each microcell of the plurality of microcells with an electrophoretic medium comprising electrically charged pigment particles, a charge control agent, and a non-polar liquid;
- sealing each microcell of the plurality of microcells with a sealing layer;
- and
- attaching a first light transmissive electrode layer onto the sealing layer.
5 more elements
A method of manufacture of a variable light transmission device comprising the steps:
- providing an assembly comprising in order a second light transmissive electrode layer, a second light transmissive electrode layer, a layer comprising a plurality of microcells being disposed on the second light transmissive electrode layer, each microcell of the plurality of microcells having a microcell opening, each microcell of the plurality of microcells comprising a microcell bottom layer, a protrusion structure, microcell walls, and a channel, the microcell bottom layer having a microcell bottom inside surface, the microcell bottom inside surface comprising an exposed microcell bottom inside surface and an unexposed microcell bottom inside surface, the protrusion structure having a protrusion base, a protrusion surface, a protrusion apex, and a protrusion height, the protrusion apex having shorter distance from the microcell opening than all other points of the protrusion structure, the protrusion height being the distance between the protrusion base and the protrusion apex, the protrusion surface being the surface of the protrusion structure not including the protrusion apex and the protrusion base, the microcell walls having a microcell inside wall surface and a microcell wall upper surface, the channel having a channel height, the channel height being 50% of the protrusion height, the unexposed microcell bottom inside surface being in contact with the protrusion base, the channel being a volume between the exposed microcell bottom inside surface, the protrusion surface, and the microcell inside wall surface;
- dispensing a light blocking composition onto the exposed microcell bottom inside surface of each microcell, the light blocking composition comprising (i) light absorbing pigment particles, (ii) a polymer, oligomer, or monomer, and (iii) a solvent;
- curing the light blocking composition to form a light blocking layer on the exposed microcell bottom inside surface;
- filling each microcell of the plurality of microcells with an electrophoretic medium comprising electrically charged pigment particles, a charge control agent, and a non-polar liquid;
- sealing each microcell of the plurality of microcells with a sealing layer;
- and
- attaching a first light transmissive electrode layer onto the sealing layer.
4 more elements
Dependencies are inferred from the claim text.