Anderson R R
Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston 02114.
Arch Dermatol. 1991 Jul;127(7):1000-5.
Light reflected from skin has two components: regular reflectance, or "glare" arising from the surface, and light backscattered from within the tissue. The regular reflectance contains the visual cues related to surface texture, whereas the backscattered component contains the cues related to pigmentation, erythema, infiltrates, vessels, and other intracutaneous structures. Unlike the backscattered component, regular reflectance preserves the plane of polarization of polarized incident light. Thus, viewing skin through a linear polarizer, under linearly polarized illumination, separates the two components of tissue reflectance. Thirty patients were examined and photographed in this manner. When the planes of polarization are parallel, images with enhanced surface detail are obtained. When the planes are orthogonal, wrinkles and surface detail disappear, and an enhanced view of vasculature and pigmented lesions is obtained. Simple, clinically useful techniques are presented.
规则反射，即由表面产生的“眩光”，以及从组织内部反向散射的光。规则反射包含与表面纹理相关的视觉线索，而反向散射部分包含与色素沉着、红斑、浸润、血管和其他皮内结构相关的线索。与反向散射部分不同，规则反射保留了偏振入射光的偏振平面。因此，在线性偏振照明下，通过线性偏振器观察皮肤，可以分离组织反射的两个组成部分。以这种方式检查并拍摄了30名患者。当偏振平面平行时，可获得具有增强表面细节的图像。当平面正交时，皱纹和表面细节消失，可获得血管和色素沉着病变的增强视图。本文介绍了简单且临床上有用的技术。
