INFLUENCE OF LASER POWER OUTPUT ON THE QUALITY OF COLOUR IMAGING

This paper investigates commercial 4-beam laser diode array with 830 nm laser wavelength output which is used for creating DAD virtual image on OPC photoconductors, i.e. the future printing elements. It is possible to generate different sizes of screen elements on photoconductor, and consequently in printing process, with the controlled variation of output laser power (from 1 µ W to 12 µ W). The results have been processed colorimetrically and with the defining of color difference CIE LAB Δ E with characteristic solid tones and 50% screened area. Results obtained are interesting because of the fact that changes in prints are not fully proportional to laser power, differences also exist between different separations (especially in yellow colour), which is caused by the chemical composition of toner.