Viewing-angle diffusion film, manufacturing method thereof, and display device

A manufacturing method of a viewing-angle diffusion film, comprising following steps:

• providing an optical material and a plurality of optical parts;
• mixing the optical material with the plurality of optical parts, such that the plurality of the optical parts are located in the optical material, wherein a refractive index of each of the plurality of optical parts is greater than a refractive index of the optical material, and the plurality of optical parts have long axes and short axes intersecting each other;
• stretching the optical material along a preset direction to form an optical material layer, and arranging the plurality of optical parts in an array in the optical material layer, wherein an angle between each of the long axes of each of the plurality of optical parts and the light emitting surface of the optical material layer is greater than or equal to 0 degree and less than or equal to 45 degrees.