Abstract: An imaging system having a source of light movable with respect to a writing element and projectable thereon to generate an image. A focusing system is provided for focusing a light source which generates a first beam of light of a wavelength selected to be actinic with respect to the writing element. At least a portion of the first beam of light is absorbed by the writing element, The apparatus includes a material supply to automatically supply donor sheets and receiver sheets independently to a writing platen or drum, and to selectively load and unload the donor sheets from superposition with the receiver sheet without disturbing the registration of the receiver sheet.