Patent ID: 6191867
Filing Date: 2001-02-20
Classification: H04N

Abstract:
A method for calibrating a halftone imaging system having a radiation source for exposing an imaging element, the method comprising the steps of:forming a plurality of image regions on an imaging element with the radiation source such that each image region is defined by at least one corresponding halftone cell, wherein the halftone cells of different image regions have an equal target dot area and are exposed by the radiation source at different exposure levels;measuring a corresponding density for each image region; andsetting an optimum exposure level for the halftone imaging system as a function of the measured densities for the image regions, wherein the setting step comprises:measuring a minimum density for a non-imaged area of the element;calculating an actual dot area for each image region as a function of the measured density of each image region and the measured minimum density; andsetting the optimum exposure level based on a difference between the target dot area and the calculated actual dot area of each image region.