研究了印刷时不同网点色版叠合形成玫瑰斑的形态控制问题,探讨了形成玫瑰斑的条件及周期性变化的规律,获得了通过对色版进行水平位置的调整来精确控制所形成玫瑰斑形态的方法。研究表明,加网线数相同且加网角度差为30毅是网点重叠形成玫瑰斑的必要条件;将色版沿其加网角度方向平移半个网点周期,可实现空心和中心点玫瑰斑的相互转换;所获得的玫瑰斑形态转换方法中,色版的调整方向由沿加网角度方向转换为沿水平或垂直的变化,可实现对玫瑰斑形态的精确控制。

Rosette form control in superimposition of different dot color was studied. Rosette formation conditions and cyclical changes rules were discussed. A method to precisely control rosette form by adjusting horizontal position of color plate was obtained. The result showed that the necessary condition for dot overlap to form rosettes is the same screening lines and screen angular difference of 30 degrees; hollow and center rosettes conversion can be realized by moving color plate along the direction of screen angle half dot cycle; precise control of rosettes can be realized by adjusting color plate direction along the screen angle direction converted to horizontal or vertical direction.