Measurement of the Time-Resolved Reflection Matrix for Enhancing Light Energy Delivery into a Scattering Medium

• Main Authors: Choi, Youngwoon (Contributor), Hillman, Timothy Robert (Contributor), Choi, Wonjun (Author), Lue, Niyom (Contributor), Choi, Wonshik (Author), Yaqoob, Zahid (Contributor), Dasari, Ramachandra Rao (Contributor), So, Peter T. C. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Biological Engineering (Contributor), Massachusetts Institute of Technology. Department of Chemistry (Contributor), Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor), Massachusetts Institute of Technology. Laser Biomedical Research Center (Contributor), Massachusetts Institute of Technology. Spectroscopy Laboratory (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2014-03-03T16:14:59Z.
• Subjects: Article
• Online Access: Get fulltext

 Multiple scatterings occurring in a turbid medium attenuate the intensity of propagating waves. Here, we propose a method to efficiently deliver light energy to the desired target depth in a scattering medium. We measure the time-resolved reflection matrix of a scattering medium using coherent time-gated detection. From this matrix, we derive and experimentally implement an incident wave pattern that optimizes the detected signal corresponding to a specific arrival time. This leads to enhanced light delivery at the target depth. The proposed method will lay a foundation for efficient phototherapy and deep-tissue in vivo imaging in the near future.