chapter  9
Functional Imaging with Diusing Light
ByArjun G. Yodh, David A. Boas
Pages 46

Many materials are visually opaque because photons traveling within them are predominantly scattered rather than absorbed. Some common examples of these highly scattering media include white paint, foam, mayonnaise, and human tissue. Indeed, anyone who has held a ashlight up to his or her hand will notice some of this light is transmitted, albeit aer experiencing many scattering events. Light travels through these materials in a process similar to heat diusion.