US 12,124,144 B2
Optically anisotropic layer
Shinpei Yoshida, Kanagawa (JP); Yuta Takahashi, Kanagawa (JP); Kentaro Yamura, Kanagawa (JP); and Keisuke Kodama, Kanagawa (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Jan. 31, 2023, as Appl. No. 18/162,379.
Application 18/162,379 is a continuation of application No. PCT/JP2021/027756, filed on Jul. 27, 2021.
Claims priority of application No. 2020-132280 (JP), filed on Aug. 4, 2020.
Prior Publication US 2023/0176438 A1, Jun. 8, 2023
Int. Cl. G02F 1/137 (2006.01); G02F 1/1333 (2006.01); G02F 1/13363 (2006.01); G02F 1/1337 (2006.01)
CPC G02F 1/137 (2013.01) [G02F 1/133362 (2013.01); G02F 1/133636 (2013.01); G02F 1/133738 (2021.01); G02F 1/133742 (2021.01)] 2 Claims
OG exemplary drawing
 
1. An optically anisotropic layer formed of a liquid crystal compound, wherein:
the optically anisotropic layer has a first layer and a second layer in direct contact with the first layer along a thickness direction,
an alignment state of the liquid crystal compound in the first layer is different from an alignment state of the liquid crystal compound in the second layer,
the first layer is a layer formed by fixing an alignment state of a liquid crystal compound homogeneously aligned,
the second layer is a layer formed by fixing an alignment state of a liquid crystal compound twist-aligned along a helical axis extending along a thickness direction, and
the optically anisotropic layer satisfies a relationship of Expression (2A) in a case where a region within a square having a largest size that can be drawn on a surface of the optically anisotropic layer is subdivided into 64 square-shaped sub-regions having the same area, a thickness d1 of the first layer and a thickness d2 of the second layer at a center position of the sub-region are obtained, X represented by Expression (1) for each sub-region is calculated, and among the calculated 64 X's, a maximum value is defined as Xmax and a minimum value is defined as Xmin,
X=d1/(d1+d2)  Expression (1)
Xmax/Xmin<1.10  Expression (2A).