Early Arriving Transmitted Photon Intensity through Tissues

Abstract

The intensity of transmitted ultrashort laser pulses through thick biological tissue within various arriving time windows were studied. It was found that intensity of the early arriving photons decay exponentially with a factor ≈z/l t , which decay much slower than the first arriving ballistic photons (z/l s ), where z, l t , and l s is thickness, transport mean free path, and scattering mean length of the medium, respectively. This results show that by using near infrared ultrashort laser pulses there may be enough early arriving photons to be used to image through a thick tissue.