Theory and experiments of a new stereoprojection technique that uses a white-light optical image processing system are described. The stereoprojection can be accomplished in two steps: (1) Spatial encoding of stereoscopically-coupled images, and (2) spatial polarization filtering at the Fourier plane in a white-light optical image processor. Comparing with existing stereoprojection methods, the present technique requires only one projector and a single piece of encoded film, therefore it is much simpler and more economical for practical applications. From the point of view of optical filtering at the Fourier plane, the polarization concept is new. If the spatial frequency of the Ronchi grating used in the encoding is high enough, there should be little loss in picture resolution.