目的 研究超四色打印机中常见的 Lc 与 C， Lm 与 M， Lk 与 K 原色和浅色双浓度墨水映射问题。 方法 采用色度中明度匹配的方法， 通过多项式拟合建立浅色墨与原色墨之间的映射关系， 并根据不同拟合次数和不同打印分辨率进行精度对比。 结果 低分辨率打印（720 dpi）二次拟合后匹配点的最大色差为 14.33， 四次拟合后匹配点的最大色差为 4.59； 高分辨率打印（1440 dpi）二次拟合后匹配点的最大色差为 21.60， 四次拟合后匹配点的最大色差为 8.72。 结论 四次拟合二次拟比二次拟合能够取得更高的精度， 并且低分辨率打印（720 dpi）比高分辨率打印（1440 dpi）的映射精度更高。 研究包含基色和浅色的两级颜色通道的多色分色具有重要意义。

Objective To study the double chroma ink mapping of Lc & C, Lm & M, and Lk & K, which are commonly used in most multi-color inkjet printers. Methods Based on colorimetric matching， polynomial fitting was used to establish a mapping relationship between every pair of double chroma ink, and the fitting accuracy was contrasted between different fitting times and different printing resolution. Results The maximum color difference of matching points was 14.33 suing two times fitting after low-resolution printing (720 dpi), and that of four times fitting was 4.59. The maximum color difference of matching points was 21.60 suing two times fitting after low-resolution printing (720 dpi), and that of four times fitting was 8.72. Conclusion Experimental results showed that the four times fitting could achieve higher accuracy than the conic fitting, and the mapping accuracy of low printing resolution (720 dpi) was higher than that of high resolution (1440 dpi). The study is of great significance for color separation of printer with two levels of color channel.