Self-calibrated frequency domain diffuse optical spectroscopy with a phased source array
Abstract
In this paper, we show that interfering multiple photon density waves created by intensity-modulated sources in frequency domain diffuse optical spectroscopy (fd-DOS) can be used to recover the optical properties of homogenous and heterogeneous tissues. While fd-DOS can recover the optical properties of homogenous tissue using a single source-detector pair, heterogeneous or layered tissues such as breast, brain, and skin require additional source-detector pairs with multiple separations. Through modelling, we show that the varying illumination patterns created by the interference of two intensity modulated sources can be used to recover the optical properties of two-layer tissue using only a single detector and two phased sources. Two-dimensional fd-DOS models of the conventional multi-distance and proposed multi-phase approaches were compared for homogenous and two-layered tissues. In a homogenous tissue with absorption and reduced scattering coefficients representative of human breast, the simulation results showed that both multi-distance and multi-phase approaches are capable of recovering the absorption and reduced scattering coefficients of the tissue. However, the multi-phase approach has less precision than the conventional multidistance approach. In the two-layer model, the multi-phase approach was capable of recovering the optical properties of both layers, while the multi-distance approach could not.
Yide Zhang
Postdoctoral Fellow
My research is interdisciplinary and focused on developing new types of optical imaging techniques that could advance the work of other researchers and medical personnel in a wide variety of fields. Currently, I am developing next-generation photoacoustic and ultrafast imaging techniques that can observe biological and physical phenomena that are too fast to be imaged with existing methods. The observation of the ultrafast phenomena could provide a better understanding of the fundamentals of life and physical sciences. I am also developing novel quantum imaging approaches that can investigate biological organisms with an imaging performance that cannot be achieved using classical optical imaging. In my free time, I enjoy cooking, hiking, cycling, and traveling.