PURPOSE: To see the position of an original image from the rear face of an original to recognize easily this position visually without making a device large-sized neither complicating the structure, by lighting a bar-shaped exposure light source to irradiate the original from the lower face of an original supporting plate before slit exposure scanning is started.

CONSTITUTION: An exposure lamp 11 is lit not only in the normal exposure operation but also by operation of an original visual recognizing push-button switch 19. When this switch 19 is depressed after a platen cover 4 is opened to place an original 5 on a platen glass 3 with the picture face turned down, the exposure lamp 11 is lit to irradiate an original part 5b indicated by oblique lines, and parts 5a to be copied of the original 5 are seen through. Consequently, an operator shifts the original 5 on the platen glass 3 vertically and horizontally to position it while seeing the picture of characters, patterns, etc. of the original 5, and the picture of the original 5 is copied in a required position of a form.