Abstract: A positive image is formed by imagewise passing a current through a substantially uniform layer of physically developable catalyst having a coverage of 1 .times. 10.sup.-6 to 1 .times. 10.sup.-10 g/cm.sup.2. The catalytic ability of the catalyst layer is destroyed by subjecting the image areas to greater than 1 .times. 10.sup.-8 coulombs/cm.sup.2. Physical development of the thus exposed catalyst layer produces the positive image. A photoconductive element which is useful in this process is also disclosed. This photographic element comprises:(1) a non-catalytic conductive support;(2) a substantially uniform first layer coated on the conductive support comprising a physically developable catalyst having a coverage of 1 .times. 10.sup.-6 to 1 .times. 10.sup.-10 g/cm.sup.

Abstract: A method for making a color imaging device that comprises means for sensing radiation comprising a planar array of charge-handling semiconductive photosensors, at least some of the photosensors having a radiation sensing area with at least one dimension less than about 100 micrometers, and superimposed thereon, filter means for controlling access of radiation to the sensing means. The filter means comprises a transparent, polymeric dye receiving layer for receiving heat-transferable dyes and further comprises a plurality of radiation intercepting means defining a planar array of filter elements lying in the receiving layer in micro-registration with the sensing areas of the photosensors. The filter area of each intercepting means contains at least one heat-transferable dye transferred to the dye receiving layer by heating and diffusion. The heat-transferable dye absorbs radiation in at least one portion of the spectrum and transmits radiation in at least one other portion of the spectrum.