Ultrafast transit-time measurement of leaves

Ultrashort laser pulses and interferometric sampling have been used to measure the temporal profile of light transmitted through a 170 mu m thick Hibiscus rosa-sinensis leaf. The mean transit times for the transmitted light with polarization parallel and perpendicular to the incident polarization are 879 and 1010 fs, respectively. Scattered light, caused by internal reflections and refractions, produces transit-time (or pathlength) enhancement factors of 1.18 and 1.35 for parallel and perpendicular polarization, respectively. The light scattering for both polarizations does not exhibit diffusive behavior and the pathlength enhancement factor is discussed in the context of other published measurements. (C) 1998 Elsevier Science S.A. All rights reserved.