PURPOSE: To reduce the installation area by providing the screen which consists of many fine planes mutually bent in a staircase shape and is curved, and a 1st and 2nd projecting device.

CONSTITUTION: The screen 3 is installed at the position where the 1st projecting device 1 can project an image without straddling the projecting device 2 and the device 2 can project an image without straddling the device 1. Further, (n) is a certain natural number and the screen 3 has unevenness consisting of 2n steps; and the 2n surfaces of the screen 3 are denoted as surfaces A1, B1, A2, B2...An, Bn and the angle that the surfaces Ai and Bi contain is 90°, where (i) is an optional natural number between 1 and (n). Further, angles (a) and (b) at which the projecting devices 1 and 2 are viewed from an optional position are 90° and constant, Therefore. the images from the devices 1 and 2 never overlap on the same plane and have no mutual interference.