Development of a photographic package printer: a case study

摘要

A specialty area in the commercial photographic industry involves simultaneously producing a plurality of high-quality photographs of varying size and shape from a single photographic negative or digital image. The images are formed on a large piece of photographic paper by a set of lenses having specific magnifications and appropriately located between the negative and paper. Package printers are typically reconfigurable to allow different sets of images to be created; however, such reconfiguration is time consuming. Most often, a package printer is configured and then devoted to a specific format. The case study presented in this paper covers the system requirements, design and fabrication of the various lenses, exposure and color balancing of the lenses, alignment and tolerancing. An interesting aspect of this package printer project was that the client literally built everything in-house including the mechanical housing, film and paper transports, lamp houses, lenses, and coatings. A critical element of the design, fabrication, and assembly of these package printers was tolerancing. Since a large number of these package printers was to be manufactured for their in-house, management needed assurance that the unit could be reasonably manufactured and would be reliable in the several plants around the world. The emphasis of this case study is on the challenge of producibility which required close attention to the capabilities of the various fabrication groups, assemblers, and technicians employed by the client. The project was successful and untold billions of photographs have been made by these package printers.