PURPOSE: To form an image with excellent registration on the surface of a photoreceptor by using plural optical image bars in a single path multiple image color copying device.

CONSTITUTION: This copying device 10 is provided with a xerography procesing area 12 and an image write-in area 14, and the area 14 is provided with a pair of high-intensity laser radiation sources shown as lasers 33 and 33'. As the lasers 33 and 33' are strobed, pulses 62 and 62' are successively impressed crossing modulators 36 and 36'. Light beams reflected from the modulators 36 and 36' are transmitted to an exposure point on the respective photoreceptor drums 20 and 20' as optically modulated linear beams. A line image is formed in a short time and perfectly registered on the drums. Thus, the copying device provided with the image write-in area for forming the line image on the surface of the photoreceptor medium arranged in the xerography processing area is obtained.