ABSTRACT
The skin is a highly dynamic, essentially protective organ with specialized functions. Specific mechanisms for photoprotection, coloration, and photobiological responses have evolved, all of which are influenced heavily by the optical properties of skin. This chapter presents useful, approximate model of skin optics, elucidates different mechanisms of skin photoprotective response for different parts of the optical spectrum. It also presents data on skin optical properties, and discusses ways of altering skin optics that are useful in phototherapy. The chapter explores the basis for laser therapy that relies on heterogeneous optical absorption. The optics of skin is highly dynamic, vary widely with pigmentation and other factors, and constitute part of the skin's functions of photoprotection and appearance. Despite the complexity with which light absorption and scattering interplay to create skin optics, a useful and approximately accurate model can be described. Noninvasive optical diagnostic techniques are still in an early stage of development.
