Abstract: This apparatus forms and displays sequentially a plurality of three-dimensional images. Frames from a film strip are stroboscopically selected and projected on a moving screen. The effect may be simply a comparison of two three-dimensional images. Alternatively, an illusion of motion of a three-dimensional image may be created. Safety features prevent access to rotating parts and other features protect the stroboscope from excessive and unnecessary use. A single three-dimensional image may be selected and continuously projected on the screen.

Abstract: This invention utilizes a series of two-dimensional photographs of successive cross-sections of an object. The photographs are arranged on a film strip in the order in which the successive sections appear in the object. The film strip is transparent and is intermittently illuminated as the successive frames of the film strip move across an optical path. A projection screen in the optical path is moved with respect to the optical path so that as each successive photograph is illuminated, that photograph is projected onto the screen at a successive position and so that each photograph as projected on the screen appears more remote from an observer than the preceding one. Thus there is formed on the screen a series of images which appear to an observer having persistence of vision to be a composite three-dimensional imgage. The illuminating means may omit the illumination of certain photographs of the series, so that only selected photographs are reproduced on the screen.