Switchable light-collimating layer with reflector
AssigneeE Ink California, LLC
InventorsXiaolong ZHENG, Pubudu Thilanka GALWADUGE, Craig LIN, Yih-Ming KANG, HongMei ZANG, Hui DU
Life of this patent
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Abstract
A light-collimating film including elongated chambers of bistable electrophoretic fluids. The light-collimating films are suitable to control the amount and/or direction of light incident to a transmissive substrate. Such films may be integrated into devices, such as LCD displays, to provide a zone of privacy for a user viewing the LCD display. Because the light-collimating film is switchable, it allows a user to alter the collimation of the emitted light on demand. Because the films are bistable, they do not require additional power after they have been switched to a display state.
Claims23
A switchable light-collimating film comprising:
- a first light-transmissive electrode layer;
- a collimating layer having a thickness of at least 20 μm, and comprising a plurality of elongated chambers with a portion of collimating layer between elongated chambers, each elongated chamber having an opening;
- a bistable electrophoretic fluid comprising pigment particles disposed in each elongated chamber;
- a sealing layer that seals the bistable electrophoretic fluid within at least one of the plurality of elongated chambers by spanning the opening of the elongated chamber;
- a second light-transmissive electrode layer, wherein the first and second light transmissive layers are disposed on either side of the collimating layer;
- and
- a light-reflective surface aligned with the opening of each elongated chamber, wherein the light-reflective surface does not substantially overlap with the portion of the collimating layer between elongated chambers.
A display comprising:
- a light source;
- a switchable light-collimating film comprising:
- a first light-transmissive electrode layer,
- a collimating layer having a thickness of at least 20 μm, and comprising a plurality of elongated chambers with a portion of collimating layer between elongated chambers, each elongated chamber having an opening,
- a bistable electrophoretic fluid comprising pigment particles disposed in each elongated chamber,
- a sealing layer that seals the bistable electrophoretic fluid within an elongated chamber by spanning the opening,
- a second light-transmissive electrode layer, wherein the first and second light, transmissive layers are disposed on either side of the collimating layer, and
- a light-reflective surface aligned with the opening of each elongated chamber, wherein the light-reflective surface does not substantially overlap with the portion of the collimating layer between elongated chambers;
- an active matrix of thin film transistors;
- a liquid crystal layer;
- and
- a color filter array.
Dependencies are inferred from the claim text.