Patent ID: 7969541

Claim:
A method of manufacturing a retardation film comprising the steps of: forming a metal mold in which a stripe-shaped pattern having a plurality of projections and depressions extending in a direction orthogonal to a polarization direction of a laser beam and crossing a scanning direction is drawn by irradiating a linear polarization laser beam to a surface of a base made of a metal material with the use of a femtosecond laser; forming a plurality of grooves extending in a specific direction on a surface of a substrate with the use of the metal mold; coating the surface on which the plurality of grooves are formed of the substrate with a liquid crystal material having polymerizability so that the liquid crystal material is arranged in contact with the surface of the substrate; and polymerizing the liquid crystal material, wherein a pattern formed by the plurality of grooves has a periodic structure, and the periodic structure has a spread of approximately 2 to 10% in pitches of projections and depressions, and a spread of approximately 3 to 8% in angles of projections and depressions.