第36卷，第11期 2016年11月
光谱学与光谱分析 Spectroscopy and Spectral Analysis
Vol.36,No.11+pp3805-3810
November,2016
Research on Assessment Methods of Spectral Reflectance
Data Quality for Computer Color Matching HE Cheng-dong',WAN Xiao-xial*,HUANG Xin-guol-2.3,
CHEN Hua-pei', OU Li-guo',ZHAO De-fang
1. Department of Printing and Packaging, Wuhan University, Wuhan430079, China
2. School of Packaging and Material Engineering, Hunan University of Technology, Zhuzhou 412007, China
3. Time Publishing and Media Co. , Ltd. , Hefei 230071, China 4. Changde Jinpeng Printing Co. , Ltd. , Changde 415000, China
Abstract Spectral reflectance data quality is important for computer color matching. There are two existing methods for evaluating the qualityspectral reflectance method and K/S method, which are too complex to apply. In this paper, 45°/o° and d/8° geometric conditions are used in the measurement of spectral reflectance of the offset ink samples printed on coated paper and silver-foiled paper while improvement on the geometric condition is made on the basis of the spectral reflectance method. Moreover, a new evaluation method—light-ness and chromaticity comparative method is put forward, and comparison is made among the three methods. The results show that both 45°/o° and d/8° are feasible in the measurement of spectral reflectance of coated pa-per; however the former one cannot meet the requirement of spectral reflectance measurement of silver-foiled paper. In addition, as to d/8° Specular Component Included (SCD , when the silver-foiled paper is taken as the substrate, the reflectance of transparent white ink samples are smaller than that of other primary inks; and ab normal intersections appear in the curves of cyan and magenta ink respectively at the concentration of 6o % , re-sulting in a poor spectra quality at high ink concentration; In the figure of lightness and chromaticity curves, there is significant divergence of the cyan and magenta ink curves from the referenced coated paper. In conclu-sion+ the spectral reflectance of the transparent ink should be greater than or at least equal to other primary inks, and the maximum concentration of cyan and magenta should be limited; when the coated paper with good diffusion performance is taken as the reference, the comparative analysis is more intuitive than the two existing methods.
Keywords Geometries
Computer color matching; Basic color samples; Spectral reflectance data; Quality evaluation:
中图分类号：0433
Introduction
文献标识码：A
D0I: 10. 3964/j. issn. 10000593(2016)11-3805-06
the prerequisite for computer color matching. Spot color is widely used in packaging printing industry so that the accura-cy of spot color is of vital importance for the quality of print-
The spectral reflectance data of primary ink samples is Received: 2015-11-12; accepted: 2016-03-10
ing products with spot colors. Usually at least three primary
Foundation item: National Basic Research Program of China (2012CB725302) ,National Natural Science Foundation of China (61275172) ,Na
tional Natural Science Foundation of China ( 61575147) , Postdoctoral Research Foundation of Anhui province, China(2015B060)
Biography: HE Cheng-dong, (1990—) graduate student of Wuhan University
万方数据ondingauthor
e-mail : wan@ whu. edu. cn
e-mail:heironhand@163.com