Method for forming multiple images on a photographic film

A method and apparatus for generating a negative or positive image from a single photographic medium. A source of radiant energy is projected onto a sheet of dielectric material heating the material to a polarizing temperature. A pair of electrical conductors are moved in a first direction along the surface of the heated dielectric material polarizing the material in the first direction. A photographic mask is then positioned over the polarized material and the radiant energy and the electrical field is again applied through the mask in a second direction to polarize certain portions of the material in the second direction. Projecting polarized light through the dielectric material and rotating the material during the projection produces a negative or positive image on the screen.