Optical printer with micromirror device

摘要

An optical printer has a DMD as a spatial light modulator. An optical image corresponding to a picture frame is projected from the DMD onto a photographic paper in a variable size to print the picture frame in a designated print size. When a maximum print size is designated, image data stored in three color image memories is entirely converted into mirror drive data for driving all micromirrors of the DMD in accordance with the image data. When a smaller print size is designated, the image data is thinned to reduce the image data size in correspondence with the smaller print size. Also a smaller area of the DMD is selected as an active area in which micromirrors are driven in accordance with the thinned image data, to print a picture in the smaller print size.