Patent ID: 7128966

Claim:
An antireflection film comprising: a transparent substrate, a polymer electrolyte film made of a polymer electrolyte, provided as a multi-layered film that is made of not less than two kinds of polymer electrolytes and the polarity of the adjacent layers are different from each other, that is formed on the surface of the transparent substrate, and at least one layer of a fine particle layer that is allowed to adhere to the polymer electrolyte film by at least an electrostatic interaction and made from at least a single layer of fine particles, wherein a surface of the transparent substrate and the fine particles are allowed to adhere to each other by at least an electrostatic interaction, which is achieved, through the polymer electrolyte film, by using fine particles having a polarity different from the polarity: anion and cation, that the polymer electrolyte film has, while the bulk of the fine particle layer is set to have a refractive index lower than the refractive index of the transparent substrate, and an average particle size of fine particles used in the fine particle layer is not more than 300 nm.