US 11,852,950 B2
Light beam direction control element, display device, and method for manufacturing light beam direction control element
Masanori Shirokawa, Kanagawa (JP); and Mamoru Okamoto, Kanagawa (JP)
Assigned to TIANMA JAPAN, LTD., Kanagawa (JP)
Filed by TIANMA JAPAN, LTD., Kanagawa (JP)
Filed on Mar. 17, 2023, as Appl. No. 18/185,761.
Claims priority of application No. 2022-058156 (JP), filed on Mar. 31, 2022; and application No. 2022-191434 (JP), filed on Nov. 30, 2022.
Prior Publication US 2023/0314897 A1, Oct. 5, 2023
Int. Cl. G02F 1/29 (2006.01)
CPC G02F 1/29 (2013.01) 9 Claims
OG exemplary drawing
 
1. A light beam direction control element, comprising:
a first light transmission substrate including a first light transmission electrode on a main surface;
a second light transmission substrate facing the first light transmission substrate and including a second light transmission electrode on a main surface facing the main surface of the first light transmission substrate;
a plurality of light transmission regions arranged in a predetermined direction and interposed between the first light transmission substrate and the second light transmission substrate;
a plurality of light absorption regions located between the light transmission regions;
a light transmission dispersion medium enclosed in the light absorption regions; and
electrophoretic particles absorbing light, dispersed in the light transmission dispersion medium, and having a dispersion state changed by an applied voltage, wherein
each of the light transmission regions includes a first light transmission region extending perpendicularly to the main surface of the first light transmission substrate from the main surface of the first light transmission substrate toward the second light transmission substrate and a second light transmission region extending perpendicularly to the main surface of the first light transmission substrate from an upper surface of the first light transmission region toward the second light transmission substrate,
each of the light absorption regions includes a first light absorption region located between the first light transmission regions and a second light absorption region located between the second light transmission regions,
a height of the first light transmission region from the main surface of the first light transmission substrate is lower than a height of the second light transmission region from the upper surface of the first light transmission region, and
when viewed in a cross section including the predetermined direction and perpendicular to the main surface of the first light transmission substrate, a width of the first light transmission region is wider than a width of the second light transmission region.