| 摘要 |
PURPOSE:To enhance gradation of a copied image in electrophotographic copying, by using a 50-300 mesh white screen overlaid on an original image face in an electrophotographic exposure. CONSTITUTION:An original containing both a portrait photoraph and letters is used and a white screen made of nylon is overlaid on the image face of the original. Electrophotographic copying using 9 kinds of screen of 50, 75, 100, 125, 200, 250, 300, 350 meshs and no screen is tested and the results are compared. The no screen test results in forming areas attached too densely with toner and too poorly, and disabling a portrait to be expressed by defficiency of gradation. Use of 70-250 mesh white screen enhances gradation of a copied image. |
