公开(公告)号：JP2003101779A

公开(公告)日：2003-04-04

申请号：JP2002194034

申请日：2002-07-03

Applicant: IBM

Inventor： TRELEWICZ JENNIFER QUIRIN ,  DITTRICH DANIELLE K ,  QIAO YUE ,  THOMPSON GERHARD ROBERT ,  WU CHAI WAH

IPC: B41J2/52 ,  G06K15/02 ,  H04N1/405

Abstract: PROBLEM TO BE SOLVED: To provide technique to realize digital half tone which controls a spot function in order to cope with gear noise, printer stress and general printing quality. SOLUTION: A method for forming spots to be used for realizing half tone includes a step for defining a spot function combining two functions which are selected in order to provide a prescribed spot form to be used in a half tone cell, and a step for scaling the spot function by using a scaling function which changes in accordance with values of a first spot function ordinate and a second spot function ordinate. By using asymmetrical modulation of the spot function, contact of adjacent spots is controlled, and a form of the spot accompanied by a gray region is changed.