The invention relates to a device for exposing light-sensitive materials, with an electronic picture memory (2) for storing a master image, with an exposure unit which comprises a light source (22), an electronically activatable light modulator (21) for representing a part picture (24) of the master image (2), and imaging optics (23) for the projection of the part picture (24) onto the light sensitive material (10), with a drive device consisting of motors (9) and of a motor control (12), for moving the exposure unit (8) parallel to the surface of the light-sensitive material (10), with a scroll means (7) for scrolling a picture strip (25, 26) of the master image through the light modulator (21), and with a control device (1) for synchronizing the drive device (9, 12) with the scroll means (7). For reducing the processing time for the exposure of the complete printing plate (10), according to the invention, it is envisaged for a rapid intermediate memory (16) for storing a strip-like region to be provided, from which the picture data for the part picture (24) to be exposed, in each case, may be transmitted onto the light modulator (21) synchronously with the movement of the exposure unit (8).