Optical element and a method for forming the same

Abstract

An optical element includes a light-transmittable substrate and a light-transmittable dry-light-curing-film layered on the substrate and having an undulant pattern on a surface thereof, characterized by the dry-light-curing-film has a specific range viscosity at room temperature in the unhardened state, a specific range thickness in the unhardened state, the specific range creep and creep recovery characteristics. A method of making an optical element includes steps of: providing a molding die having an undulant pattern on a surface thereof; providing a dry-light-curing-film has a specific range viscosity at room temperature in the unhardened state, a specific range thickness in the unhardened state, the specific range creep and creep recovery characteristics; pressing the film onto the surface of the molding die by a roller under heated and reduced pressure conditions to form undulant pattern on the film; affixing a light-transmittable substrate to the film while pressing the substrate by a roller under an increased pressure condition to form a laminate; irradiating an UV radiation into the film to harden the film; and separating the molding die from the film to form an optical element.