ABSTRACT
Figure 2.4 This is a schematic representation of optical properties of light during the use of contact NPD with a liquid interface. The arrows indicate the path of light through the skin. Most of the light is absorbed and refl ected from the superfi cial layers of the epidermis after undergoing minimal scattering events (thick red line). Some of the light is refl ected off the stratum corneum (thin blue line) but this surface glare is insuffi cient to interfere with the ability to visualize subsurface dermoscopic structures. Some of the light penetrates more deeply and is absorbed and refl ected back after multiple scattering events (thin black line); however, the light from the deeper layer contributes only a small fraction to that detected with NPD, and most of the light reaching the retina is from the more superfi cial, minimally scattered light (thick red line). Abbreviation: NPD, nonpolarized dermoscopy.
