Patent attributes
Light irradiation is performed on a strip region on a photosensitive material by main scanning of an irradiation region group on the photosensitive material where light emitted from a micromirror group of a DMD is directed and light is applied to a plurality of strip regions partially overlapping in a sub scan direction in turn while repeating the main scanning, to write a pattern on the photosensitive material. When a preceding irradiation region group and a following irradiation region group pass over an overlapping area, a part of micromirrors corresponding to the overlapping area, out of the micromirror group, are made inactivated. As a result, a cumulative passage time in which the preceding irradiation region group and the following irradiation region group pass each position of the overlapping area is shorter than a passage time where the preceding irradiation region group passes each position of a non-overlapping area.
