PURPOSE: To easily spread a screen when it needs to be used and to easily fold it when it need not to be used by attaching a flexible screen which can be folded to a rib part which radially unfolds.

CONSTITUTION: In the case of spreading the screen, a movable cylindrical body 24 is moved along a supporter 10 to the tip side of the supporter 10. The movable cylindrical body 24 gets over an pawl 26 and stops at a position where it abuts on a stopper 25. Since the pawl 26 is restored by a spring which is installed in the supporter 10 at such a time, the cylindrical body 24 is prevented from returning to a home position. When the cylindrical body 24 is moved upward, the rib part 20 is pushed up by an auxiliary rib part 23 whose center side is supported by the cylindrical body 24 and is turned centering around a turn supporting part 19, so that a screen main body 22 attached to the turn supporting part 19 is spread. By turning the lower end part 11 of the supporter 10 centering around a fulcrum pin 13 in a state where a screw 14 for fixing is loosened, the angle of the lower end part 11 against the supporter 10 can be set at an optional value. The bottom end side of the lower end part 11 is supported through a knob 16, which is used also as a supporting leg.