An unusually short close-up imaging system about 8.5 cm (3 3/8 in.) long has been developed for document copiers, oscilloscope cameras, and computer peripheral hard-copy cameras. Arrays of simple lenses are molded in rows and columns on two parallel plastic lens plates. Each lens on the first lens plate forms a demagnified, inverted, intermediate image of a small area of the object in the space between lens plates. Each lens in the second plate erects and magnifies an intermediate image and places the resulting final image in partially overlapped registration with adjacent images, forming an erect uniform composite image of the whole object.
© 1979 Optical Society of America
R. H. Anderson, "Close-up imaging of documents and displays with lens arrays," Appl. Opt. 18, 477-484 (1979)