Patent ID: 8693100

Claim:
A method of manufacturing a light diffusion film, wherein the method comprises: forming a laminate of an original light diffusion film and a photosensitive resin, wherein the photosensitive resin comprises at least two types of materials that are different in refractive index from each other; and irradiating the laminate with a collimated laser beam from a side of the original light diffusion film, wherein a reflection hologram formation-preventing layer is located on a side of the laminate opposite from the side of irradiation of the laminate with a collimated laser beam wherein in the process of irradiating the laminate the reflection hologram formation-preventing layer prevents formation of a reflection hologram on the photosensitive resin due to a reflected light from the irradiation, wherein the reflection hologram formation-preventing layer is a layer with surface unevenness, and wherein the surface unevenness has Sm (mm) in a range from 0.001 to 1 and Ra (μm) in the range from 0.01 to 10.