Projection screen

DETAILED DESCRIPTION In view of prior art, it is a general object of the present inventio to provide a projection screen which ahs even reflected light distribution, higher light efficiency, lower energy cost, higher resolution and contrast, and lower operating cost.
It is another object of the present invention to provide a projection screen which could be portable and is of a shape which can be set thereby matching the distribution of the audience and the size and shape of the theater.
In keeping with the principles of the present invention, the objects are accomplished by a unique projection screen including an elongated film having a front surface, a back surface and a periphery, a means for defining at least one curve of the periphery of the elongated film in a plane normal to the periphery of the elongated film, a means for creating a pressure differential betwen the front surface and the back surface of the film, a means for sensing the position of the elongated film and a means for controlling the means for creating the pressure differential in response to the means for sensing the position such that the position is a predeermined position whereby the shape of the elognated film is set by the means for defining a curve of the periphery of the film and by the predetermined position.