Optical element, directional diffusion film, and method of manufacturing optical element

A method of manufacturing an optical element comprising a plurality of through holes in a transparent film matrix, wherein the plurality of through holes are placed in a state where axial directions thereof are approximately in parallel with one another, the axial directions of the through holes are inclined or approximately parallel to a thickness direction of the transparent film matrix, and the through holes are filled with a low-molecular substance, and wherein

• the method comprises processes of:
• providing an optical element-forming material containing a monomer having a photopolymerizable functional group and the low-molecular substance, the difference between the SP values thereof being in a range from 1.5 to 3;
• forming an optical element-forming material layer by coating a first substrate with the optical element-forming material;
• and
• irradiating the optical element-forming material layer with a parallel beam.