Print quality test target: developed to test postscript printers

摘要

Abstract: Until now, computer publishing system lacked control systems like those used for offset printing. The objectives of the VFG-GLV- PostScript-targets were to develop test targets, which enable any user to evaluate and maintain the quality of any output device (printer or imagesetter). These test targets should be supplier independent. Developing the test targets started early in 1990 at the Institute for Graphic arts in Vienna (Graphische Lehr- und Versuchsanstalt, GLV). The first prototypes were used at CeBIT 1990 for an imagesetter comparison. In 1991 the concept was refined, giving two test targets: the VFG-PTF and the VFG-PQF. After field testing in 1991, they are available around the world since September 1991. The test targets were developed using direct PostScript programming. Main parameters of the output device are interrogated and are used to build test targets suited for a specific device resolution on the fly. Some test targets are device dependent and show output quality for a specific device at a specific resolution. This is the advantage of a test target, created by a program. It allows to deal with specific devices. The test targets are therefore suited to test imagesetters at high resolutions as well as low-res laserprinters. The VFG-PTF test target helps evaluate the quality of a PostScript printer or imagesetter. Its size of 20 $MUL 20 cm allows for a large quantity of test targets. The test target checks resolution, screen angles, density, and the quality of mechanical and optical system. The evaluation of the test targets will be done visually or using a densitometer. The VFG-PQF test target is used for job quality control. It is pasted into a PageMaker, Ventura Publisher, or XPress job and will be sent to the printer with the job. This allows quality control for every page processed.!0