| 摘要 |
PURPOSE:To suppress unevenness in tint or color and irregularities in density by a method wherein a dot pitch in the direction of feed is determined to be 1/3n (mm/dot) or less independent of a dot pitch in the direction of main scan ning when the number of reflecting surface of a rotating polyhedron is (n). CONSTITUTION:In an image recorder 10, a dot pitch in the direction of feed is determined to be 1/3n (mm/dot) or less independent of a dot pitch in the direction, of main scanning, where (n) is the number of reflecting surfaces of a polygon mirror 16. Therefore, it is preferable that a beam spot on a recording material 40 is shaped to have a diameter in the main-scanning direction larger than a diameter in the feed direction. In this manner, unevenness in tint or color and irregularities in density caused by, e.g., an error of a reflectance of the polygon mirror attributed to a difference of a wave length of an optical beam are not visually conspicuous or recognized, even if occurred. An image with a good gray balance improved in color balance and density balance can be recorded all over the surface. |
