基于光散射概率函数的半色调反射率模型  

Halftone Printing Reflectance Model Based on Light Scattering Probability Function

作　　者：刘萧豪 王琪[1] 

机构地区：[1]南京林业大学江苏省制浆造纸科学与技术重点实验室,南京210037

出　　处：《包装工程》2014年第1期108-113,共6页Packaging Engineering

摘　　要：目的以调幅和调频网点为研究对象,针对2种网点分别建立半色调反射率模型,并将网点结构的差异引入模型。方法基于Murray-Davies模型理论推导半色调反射率模型,并以不同光散射概率函数体现不同网点结构。采用数学显微采集系统对半色调印品进行了数字化采集,将数字图像灰度值转化为对应的反射率值,通过分析反射率直方图极值特征得到半色调印品空白反射率和着墨部分反射率,再经数据拟合确定理论推导模型中的参数。结果基于总反射率和光谱反射率的验证实验,结果表明调幅和调频网点模型拟合优度判定系数R2分别为0.9821和0.9520。结论所建立模型能够体现网点结构的差异,精度高,适用性强。Objective To establish reflectance models for AM and FM dots which take the difference of dot structure into account. Methods Based on light scattering probability function which describes the optical properties mathematically and the Murray-Davies model, reflectance models suit for different dots were inferred. Halftone printings＂ gray values digitized by microscopic acquisition system were transformed into reflectance values. Through the reflectance histogram, the reflectance of not printed paper and printed ink was obtained. By means of fitting measurement reflectance and model predicted reflectance, parameters of the model were determined. Results The evaluation based on total reflectance and spectral reflectance indicates that the R2 of AM dots model and FM dots model is 0.9821 and 0. 9520. Conclusion The models for AM and FM dots are accurate and applicable.

关 键 词：光散射概率函数 调幅网点 调频网点 反射率模型 

分 类 号：TS801[轻工技术与工程]