Diffuse Photon Density Waves In The Internal Transmission Characteristics Of Biological Tissue Simulation And Experimental Study

In this article the property of DPDW transmitting through Bio-Tissue produced by illuminating of continuous waves was studied in simulations and experiments. The effect to the transmittance of DPDW when an abnormal object was contained in tissue was also discussed.On the basics of DPDW's theory, a program that could show the process when a photon walk through the tissue and the parameters of source and tissue could be inputted on the interface and the result can be given with gray pictures and TXT documents was programmed. The result was simple and could be analyzed easily.By making full use of the program to simulate the spread of photons when changing the parameters of tissue, some new phenomena was found and explained. The situation of multiplayer and abnormal objects contained in monolayer tissue was also discussed. As a result, the position and size of abnormal objects could be detected by Monte Carlo simulate.The rarely milk solution (the concentration of quality is about 1E-5) was studied qualitatively with 650nm LD. The visibility of abnormal objects hidden in the solution and the variety of speckle in the surface of transmission were investigated too. From the result, with the acceleration of concentration of scattering particle, the abnormal objects embedding in the solution could be see clearly, but the speckle in the surface of transmission was diminished, and the solution became brightly.In this article, the best wavelength used to diagnose those changes in tissues was analyzed. The 808nm laser emission system and the photoelectric detector working under reversed voltage were designed. The distributing of intensity of transmitted light with and without abnormal objects was tested in monolayer and double-layers of pork tissue with the thickness were 0.3cm and 0.6cm. From the distribution of intensity of transmitted light that was inversed from the data of experiments, the biggish abnormal object ( F2.5mm) can be see obviously. But the lesser abnormal object (F0.5mm) cannot be founded. One the one hand the reason was the position and size of abnormal object; on the other hand was the lower resolving power of detector. In the last part of this paper, the Monte Carlo simulation was processed with the same parameters. The experiment and simulation were fit well.It can be conclude that the Monte Carlo simulation is an effective method to simulate the transmittance of photons walk in tissues. And the fact that the embedded abnormal object can be detected form the experiments and the simulations with DPDW. The research result will provide theoretical and experimental reference to Tissue Optics, Biomedical Photonics, Medical Diagnose and corresponding fields.