Anti-peep film and manufacturing method thereof, and display module

An anti-peep film, comprising a top substrate, a bottom substrate, a plurality of transmission areas and a plurality of anti-peep areas 20, wherein the plurality of transmission areas and the plurality of anti-peep areas 20 are alternately arranged between the top substrate and the bottom substrate in a direction parallel to the top substrate and the bottom substrate;

• wherein each one of at least one anti-peep area of the plurality of anti-peep areas comprises
• a plurality of prisms arranged in a direction perpendicular to the top and bottom substrates and
• anti-peep layer arranged between the plurality of prisms and transmission areas adjacent to the at least one anti-peep areas, and
• light incident on the transmission areas adjacent to the at least one anti-peep area from a first side of the anti-peep layer in the direction perpendicular to the top and bottom substrates transmits to inside of at least one prism of the plurality of prisms, is totally reflected at interfaced between the anti-peep layer and the at least one prism, then exists the at least one prism and transmits back to the first side;
• wherein the at least one prism of the plurality of prisms is a quadrangular prism or a pentagonal prism;
• wherein a refractive index of at least one transmission areas adjacent to the one anti-peep area is smaller than a refractive index of the at least one prism;
• wherein
• the at least one prism comprises an incident surface, a first total reflection surface, a second total reflection surface, and an emission surface;
• the interfaces between the anti-peep layer on both sides comprises the first total reflection surface and second total reflection surface, the light transmits to the inside of the at least one prism through the incident surface and exists the at least one prism through the emission surface;
• an angle between the light and a direction parallel to the top substrate and the bottom substrate satisfies a preset angle range,
• wherein along the direction perpendicular to the top and bottom substrate and away from the first side, angles between respective pairs of first and second total reflection surfaces of the plurality of prisms decrease, and angles between respective pairs of incident and emission surfaces of the plurality of prisms increase.