New Multi-level Error Diffusion Method for Improving the Rendition of High-light Area

Abstract

We developed a new half-tone rendition method for electrophotography. This method is based on conventional multi-level error diffusion method. It switches threshold levels adaptively according to the signal of preceding pixels, so that it suppresses to output isolated narrow signal, which causes unstable rendition.
We calculated potential histgram of latent image, by computer simulation, and confirmed that frequency of lower potential is reduced, as we desired. By experiments by actual printing, we confirmed that this method realized linear gradation characteristics, higher rendition and lower noise level at high-light area, comparing with conventional methods.