Time-Gated Imaging Through Scattering Materials With Nonlinear Raman Techniques

Time-gated imaging offers the potential for imaging objects that are embedded in or viewed through dense scattering materials. We have developed several time-gated imaging techniques based on nonlinear optical Raman interactions. As a class these techniques allow real-time two-dimensional imaging, time resolutions ranging from hundreds of femtoseconds to tens of picoseconds, photon gain up to 108 and an inherent noise level of one photon per mode, allowing for detection of a minimal number of transmitted photons. The authors have used these techniques to study the characteristics of imaging through scatterers such as non-dairy creamer, suspensions of microspheres, and chicken tissue