In an exposure apparatus, a photomask 3 is provided with a plurality of mask pattern columns 15 formed by arranging a plurality of mask patterns 13 at a predetermined pitch in a direction substantially orthogonal to a conveying direction A of an object to be exposed and a plurality of microlenses 14 formed on a side of the object to be exposed corresponding to the mask patterns 13 to project reduced mask patterns 13 on the object to be exposed The photomask 3 is obtained by forming subsequent mask pattern columns 15b to 15d and the microlenses 14 corresponding to them so as to be shifted by a predetermined dimension in an arranging direction of a plurality of mask patterns 13 from a mask pattern column 15a located downstream in the conveying direction A of the object to be exposed.