Abstract: A continuous inkjet device emits a stream of fluid from nozzles. Droplet break-off is stimulated by the application of external perturbing stimulus to the stream in a manner that controls the formation of satellite drops. Satellite behavior is controlled by the use of a composite perturbing signal, composed of at least two frequencies that are not harmonically related, but are related by the ratio of small integers. In one embodiment, the use of two perturbing signals with frequencies fL and fH having a ratio of M/N, where M and N are integers, and M is not a multiple of N, and N is not a multiple of M, produces a repeating drop pattern of either M or N drops at the beat frequency of the combined signal, the constituent drops in said repeating pattern have different satellite formation characteristics.

Abstract: Methods and apparatus for determining the optimal adjustment of imaging systems used to prepare lithographic printing surfaces for a printing press are described. A series of test patterns are imaged while varying a particular imaging parameter. This is followed, if necessary, by processing the plate in processing line. The plate is then returned to the digital imaging system where the reflectivity of the imaged test patterns is measured using a radiation source and detector, to determine the optimal setting for the parameter.

Abstract: Methods and apparatus for determining the optimal adjustment of imaging systems used to prepare lithographic printing surfaces for a printing press are described. A series of test patterns are imaged while varying a particular imaging parameter. This is followed, if necessary, by processing the plate in processing line. The plate is then returned to the digital imaging system where the reflectivity of the imaged test patterns is measured using a radiation source and detector, to determine the optimal setting for the parameter.