Method and apparatus for inverting the polarity of an input image formed on a surface of an image recording device

Abstract

Method and apparatus for inverting the polarity of an input image formed on a surface of an image recording device which deforms when illuminated in the presence of an electrostatic field applied thereacross. The image recording device, comprising a layered structure consisting of a conductive transparent substrate, a photoconductive layer, a deformable elastomer layer and a deformable, reflective layer is raster scanned by information containing light through the photoconductor layer with voltage applied between the conductive electrodes, the elastomer and deformable electrode being deformed in accordance with the input information. The image projected from the surface of the deformable electrode is positive, light characters on a dark background. In order to project a negative image (dark characters on a light background), the device is initially flooded with light through the photoconductor layer with voltage applied between the conductive electrodes. The voltage is then removed for a predetermined time period. With the voltage removed, the photoconductor layer is raster scanned by an information containing light spot, the light spot writing characters in selected areas by erasing the background thereat while the remaining background area is preserved. The voltage is then reapplied, a negative image of high contrast being projected from the surface of the deformable electrode.

Dependencies are inferred from the claim text.