Abstract: A screen is constructed to have a screen case, a support member fastened to one side of the screen case and a reel pivotally mounted inside the screen case and rolling up a screen body. The reel has a flat inside stop face and a plug member is fixedly fastened to one end of the reel. An axle is suspended inside the reel, the axle having a first end fixedly fastened to the screen case and a second end fastened pivotally with the plug member. A spring member is sleeved onto the axle inside the reel, the spring member having a first end terminating in a projecting portion stopped at the flat inside stop face of the reel and a second end fixedly connected to one end of the axle.