Measurement of the time-resolved reflection matrix for enhancing light energy delivery into a scattering medium.
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.
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and Department of Physics, Korea University, Seoul 136-701, Korea.
Youngwoon
Y
Choi
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Timothy R
TR
Hillman
Department of Physics, Korea University, Seoul 136-701, Korea.
Wonjun
W
Choi
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Niyom
N
Lue
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Ramachandra R
RR
Dasari
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and Department of Mechanical and Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Peter T C
PT
So
Department of Physics, Korea University, Seoul 136-701, Korea.
Wonshik
W
Choi
Laser Biomedical Research Center, G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Zahid
Z
Yaqoob
D060733:Electromagnetic Radiation; D008027:Light; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation / Q000379:methods*; D012542:Scattering, Radiation