Stereoscopic projecting apparatus

A stereoscopic projecting apparatus which projects a stereoscopic image via a cinefilm on which left-eye pictures and right-eye pictures are alternately formed on consecutive frames, which apparatus comprises:

• a light source for projecting a beam of light toward a predetermined region;
• drive means for driving a cinefilm in such a manner that the cinefilm passes through the predetermined region toward which the light from the light source is projected;
• a prism arranged in the region through which an image transmitted from the cinefilm is passed, the prism having a plurality of planes, through which the image becomes incident or from which the image emerges, and which planes are endlessly connected;
• prism rotating means for rotating the prism about a rotating axis of the prism which includes the center of the plurality of planes and which is parallel to the plurality of planes;
• synchronizing means for synchronizing the movement of the cinefilm and the rotation of the prism, so that each of the planes of the prism becomes parallel to the surface of the cinefilm when each one of the frames of the cinefilm is located at the center of the predetermined region toward which the light is being projected, thereby projecting a moving image;
• detecting means for detecting the rotating position of the prism and producing a detection signal when one of the plurality of planes of the prism is parallel to the surface of the cinefilm, or when two adjacent planes, of the plurality of planes of the prism, are inclined at the same angle with respect to the surface of the cinefilm, in the predetermined region;
• a rotation control device for stopping the rotation of the prism upon reception of the detection signal from the detecting means, thereby two dimensionally or stereoscopically projecting a still image;
• and
• deflecting means for deflecting the images, which deflecting means deflects the left-eye image transmitted from the frame on which the left-eye picture is formed in a first direction, and deflects the right-eye image transmitted from the frame on which the right-eye picture is formed in a second direction, the first and second directions being perpendicular to each other.