Abstract

Recently, there is a growing number of researches in transillumination imaging through highly scattering media, as a result of the increased interest in optical computed tomography (CT), especially for biomedical applications. Several techniques have been studied¹ to obtain optical images eliminating multiply scattering light. A coherent detection imaging (CDI) method^2–5 can extract only coherent component from the transmitted light on the basis of an optical heterodyne detection technique. So far, amplitude of the heterodyne signal, in other words, the intensity of transmitted coherent light was used to form optical images of scattering or absorption of the objects. However, CDI inherently has a potential to measure phase difference between a signal wave and a reference one, which has information about a refractive index or an optical length of the object.

© 1996 Optical Society of America