A roller-shaped stamper has a scale portion with a light transmitting forming portion for forming the light transmitting portion on the resin, and a light shield forming portion for forming the light shielding portion of the resin, wherein the forming portions are alternately arranged with a constant pitch in a direction of rotation of said roller-shaped stamper; a plurality of scale portions are arranged in a direction normal to the direction of rotation of the roller-shaped stamper; and a groove disposed between the plural scale portions and extending in the direction of rotation of the roller-shaped stamper for exhausting air otherwise trapped between the resin and the roller-shaped stamper.