| 摘要 |
PURPOSE:To perform image conversion of an original picture including continuous gradations of varying densities by using a dot analyzing screen which is made usable in abutment on the original picture. CONSTITUTION:A dot analyzing screen 42 which is coated with only the black dots 42b as analyzing elements on a transparent sheet 42a and is arranged flatly is interposed betwen an electrostatic copier 15 and an original picture 14 in abutment thereon, and the picture 14 is transferred. As compared to a white screen or a crystal screen, superior dot analyzing power is obtained particularly in the highlighted parts. In the case of performing good image conversion from the highlighted parts to medium contrast parts of the picture 14, combination use of a black screen 42 and a white screen or a crystal screen suffices but in order to prevent moires, it is possible to use the composite screen provided with analyzing elements provided with both black dots and white dots. |
