Lab色度系统评价阳光辐射对我国人体肤色影响的实验研究

[目的 ]　研究Lab色度系统L、a、b、c、h、△E各指标在我国人群阳光肤色反应评价中的应用。　 [方法 ]　选择 10名年轻女性 ,连续 17天每天进行 6小时室外活动 ,观察暴露前及暴露后第 1、3、4、9、14、17天其额、颊、颈、手、背部肤色的变化 ,同时记录暴露期间的紫外线辐射强度 ;肤色的检测采用光谱光度计。　 [结果 ]　暴露期间到达地面紫外线强度以 42 0nm为最大 ,其次是 365nm ,2 97nm更低。各波段紫外线强度以每日中午时分最强。随照射剂量增大 ,反映肤色的指标 (L、b、c、△E)的变化相对较明显 ,尤以△E变化最大。而a、h变化不大。△E的变异系数最大。颊部、颈部肤色在暴露前后有显著变化 ,而额、手、背部变化不明显。　 [结论 ]　Lab色度系统△E评价肤色变化较为全面、灵敏 ;观察自然阳光辐射下人体肤色变化的最佳部位是颊部

Experimental study of the assessment on the effect of sun light radiation to Chinese''''s skin color by Lab color system

To study the use of L,a,b,c,h,△E of Lab-system in the assessment of chinese's skin color. The course of skin color changes on forehead,cheek,neck,hand and back induced by broad band UVA and UVB radiation were evaluated in 10 Chinese young women by means of a tri-stimulus colorimeter for 17 successive days. The radiation of ultraviolet-420nm on the ground among the course of exposure was the strongest.The second was the ultraviolet-365nm.The weaker was ultrarviolet-297nm.With the increase of exposure, the changes of L,b,c,△E were greater than that of a,h and the change of △E was the greatest. The CV of △E was the greatest. The changes of skin color on cheek and neck were significant, but the changes of skin color on forehead,hand and back were not significant. [Conclusion] Among Lab color system △E is a more appropriate index to describe a variety of human skin color under sunshine than others, and cheek is the most appropriate site to observe skin color changes induced by sunshine.