Abstract
This paper reviews the current status and future prospects of optical technologies using near-infrared light for biology and medicine. Light in the near-infrared wavelength range has higher transmittance through biological tissues, and is frequently used for measuring physiological information such as tissue oxygenation, hemodynamics, and concentrations of tissue fluids. However, light in the near-infrared wavelength range is subject not only to the absorption but also to the strong scattering by tissues. Due to this strong scattering of light by tissue light propagates diffusely in tissues. This paper focuses on the technologies of diffuse optical imaging and noninvasive measurement of blood glucose level.
