Imaging Of Scattered Light Using The Chaotic Laser Based On Single Source And Multiple Detector

With the continuous development of laser technology,the use of laser scattering technology for health detection of human tissue has become a research hotspot.The chaotic correlation optical detection technology is to collect the chaotic signal passing through the biological tissue phantom,and use the correlation peak value to realize the optical information measurement of the biological tissue phantom,and the imaging of foreign object in the biological tissue phantom.Therefore,in this paper,chaotic optical signal which amplified by fiber laser is used as the experimental light source,using Intralipid solution as a biological tissue phantom,a tube filled with water to simulate the foreign object in the tissue as an absorber.By measuring the attenuation coefficient of the biological tissue phantom and the foreign object,we can realize the detection and imaging of the size and position.The main content of the paper can be divided into the following parts:(1)The thesis introduces different types of medical detection methods,summarizes and analyzes the current development process and detection of biomedical optical detection methods.(2)The thesis analyzes the scattering characteristics of laser light through biological tissues in detail,and analyzes the loss caused by the laser propagating in the tissues which can realize the measurement of optical parameters of biological tissues and thereby realize the detection of biological tissues.(3)According to the analysis of the transmission characteristics between the beam and the biological tissue,the chaotic correlation optical detection theoretical model is established.The attenuation coefficient can calibrate the loss caused by the beam propagating in different positions,through the conversion of crosscorrelation and intensity,we can obtain the relationship between the crosscorrelation value and the attenuation coefficient and the path.Finally,the relationship between the cross-correlation value and the size and position of the corresponding foreign object can be obtained,the theory is simulated by the established theoretical model,and the chaotic cross-correlation peak meeting the attenuation law can achieve the simulation of two-dimensional imaging.(4)The Intralipid solution with a certain concentration is used as a liquid biophantom,and the tube with water is used as an absorber.The detection light signal is obtained by a transmission method,so the phantom and absorber can be analyzed.In order to better analyze the optical characteristics of the liquid biophantom and the foreign object,we use the cross-correlation peak at a certain delay to measure its corresponding attenuation coefficient through different media.The derived theoretical formula is used to calculate the size and location of the corresponding foreign object.And the CT imaging principle is used to realize a two-dimensional cross-section imaging of the placed absorber.The contrast of different attenuation levels on the imaging map can be used to detect the placement of foreign object.The results show that the chaotic cross-correlation detection method can be used to analyze the optical characteristics of the biophantom and foreign object,obtain the size and location of foreign object and realize the two-dimensional imaging,the experimental results correspond to the theoretical analysis.