Measurement Of Optical Properties Of Bio-Tissue Based On Scanning Photoacoustic Technique And Its Application For Glucose Sensing

Photoacoustic technique(PAT) which combines the optical with ultrasonic technique has a potential to map the high optical-contrast and ultrasonic spatial resolution image in biological tissue. We can get the images which have unique advantages with variety of scales, different mode for requirement of biomedicine therapy by PAT. Photoacoustic signal excited by the pulse laser include many information about biological tissue. We can obtain the biological tissue's optical parameters by analyzing the photoacoustic signal from amplitude to shape. So it could offer some tissue information and reference doses for laser surgery in clinical. In the thesis, We present a new approach which a focused ultrasound transducer scans along the axial direction to measurement of tissues' parameters. And, the preliminary study of the method for the glucose concentration is investigated.The main works of this thesis are as follows:In exordium, The developments of photacoustic technique was reviewed, including history, main tasks and scope. And the foreign and internal study groups were introduced.In chapter one, we get the solution of the PA signal propagation wave equation by Fourier transform. Meanwhile, we discussed the solution and simulated the profile of photoacoustic pressure at different time by program. And the classical systems for photoacoustic signal detection are also described in this chapter.In chapter two, we describe the present photoacoustic systems which were introduced to measuring the optical parameters of biological tissues and its mechanism based the diffuse theory. some necessary discussion was presented.In chapter three, a novel side scanning photoacoustic technique was employed to measuring the optical parameters of biological tissue. The result obtained by the technique was compared to the result simulated by MonteCarlo program. It shows striking similarity. The results demonstrate the capability of the PA technique for use in measuring the optical parameters of biological tissueIn chapter four, the effect of glucose concentration as a factor reducing optical reduced scattering coefficient was investigated by the side scanning photoacoustic technique. The experimental preliminary results are consistent with the conclusion drew by other groups fairly good. It demonstrated that the novel method is capable of detection incr?? sing glucose concentration by the optical parameter measurement.