Johnston W M, Hesse N S, Davis B K, Seghi R R
Section of Restorative and Prosthetic Dentistry, College of Dentistry, Ohio State University, Columbus 43210-1241, USA.
J Dent Res. 1996 Feb;75(2):752-60. doi: 10.1177/00220345960750020401.
Edge-losses occur during reflectance measurements of pigmented maxillofacial elastomer when light is scattered within a sample beyond that part of the surface exposed to the observation system of the optical device. A custom sample-holder is presented which redirects light that would not be measured during conventional reflectance measurement back into the sample. The amount of edge-loss occurring within thin layers of maxillofacial elastomer with tan pigment on black-and-white backings was found to depend on sample thickness, the backing, the beam size used during conventional reflectance measurement, and the optical term bS = (2KS + K2)1/2. Data analysis revealed a significant interaction among these four factors. Additionally, the edge-loss occurring during the tristimulus reflectance measurement of thick samples of maxillofacial elastomer with various concentrations of tan and black pigment was found to be linearly related to bS up to a limiting value, with no additional edge-loss occurring for bS values above this limiting value. Edge-loss is an important consideration during the matching of the optical characteristics of pigmented maxillofacial material to those of human skin.
在对有色颌面弹性体进行反射率测量时，当光在样品内部散射到超出光学设备观察系统所暴露的表面部分时，就会出现边缘损失。本文介绍了一种自定义样品架，它能将传统反射率测量过程中无法测量的光重新引导回样品中。研究发现，在黑白背景上带有棕褐色颜料的颌面弹性体薄层中出现的边缘损失量，取决于样品厚度、背景、传统反射率测量中使用的光束大小以及光学项bS = (2KS + K2)1/2。数据分析显示这四个因素之间存在显著的相互作用。此外，在对含有不同浓度棕褐色和黑色颜料的厚颌面弹性体样品进行三刺激值反射率测量时，发现边缘损失与bS呈线性关系，直至达到一个极限值，对于高于该极限值的bS值，不会出现额外的边缘损失。在将有色颌面材料的光学特性与人体皮肤的光学特性进行匹配时，边缘损失是一个重要的考虑因素。
