Optical element that functions as a liquid crystal diffraction lattice

An optical element comprising:

• an optically anisotropic layer having a laminated structure in which a first optically anisotropic layer, which is a cured layer of a liquid crystal composition containing a rod-like liquid crystal compound, and a second optically anisotropic layer, which is laminated on the first optically anisotropic layer and is a cured layer of a liquid crystal composition containing a disk-like liquid crystal compound, are laminated on each other,
• wherein the first optically anisotropic layer has a first liquid crystal alignment pattern in which an optical axis of the rod-like liquid crystal compound is parallel to a surface of the first optically anisotropic layer and is oriented along at least one in-plane direction of the first optically anisotropic layer, orientation of the optical axis of the rod-like liquid crystal compound changes continuously and rotationally along the at least one in-plane direction of the first optically anisotropic layer, and the orientation of the optical axis of the rod-like liquid crystal compound rotates by 180° with a period of 0.5 μm to 5 μm, and
• the second optically anisotropic layer has a second liquid crystal alignment pattern in which an optical axis of the disk-like liquid crystal compound is parallel to a surface of the second optically anisotropic layer and is oriented along at least one in-plane direction of the second optically anisotropic layer, orientation of the optical axis of the disk-like liquid crystal compound changes continuously and rotationally along the at least one in-plane direction of the second optically anisotropic layer, and the orientation of the optical axis of the disk-like liquid crystal compound rotates by 180° with a period of 0.5 μm to 5 μm.