| 摘要 |
A projection screen consists of an inflatable frame 3 of flexible material, a projection cloth 1 of flexible material which is tightly attached in the frame 3, and a flexible sheet 2 which is also tightly fastened against the frame 3. The cloth 1 and the sheet 2 are fastened at a distance from each other but basically parallel. The frame 3, the projection cloth 1 and the sheet 2 thereby form a closed space. A valve 5 is connected to the frame 3 to enable an inflation and thus a stiffening of the frame 3 so that the frame 3 stretches out the projection cloth 1 and the sheet 2. A valve 4 is connected to said space to enable an evacuation thereof, so that at least the projection cloth 1 can assume a spherical curved shape. The frame 3 can be extended 3a in the normal plane of the projection cloth 1 to form a shield against scattered light around the edge of the projection cloth. As an alternative, the frame 3 can be suitably provided on its outer side with preferably flexible scattered light screens 3b. <IMAGE> |
