Composition And Research Of Acoustic Resolution Photoacoustic Microscopy Imaging System

Biomedical imaging is an important means of medical diagnosis and treatment,photoacoustic imaging techniques have the unique advantages of analysis biological chemical information,it make a great contribution for accurate medical diagnosis and treatment.Photoacoustic imaging is the combination of high contrast from pure optical imaging and the characteristics of deep from ultrasonic imaging,so it widely researched and applied used in the field of biomedical imaging.The excitation source of ultrasonic signal is short pulse laser in the photoacoustic imaging,ultrasonic transducer receives the ultrasonic signal of laser inspired,the acquisition of ultrasonic signal is converted to electrical signals,finally,reconstruction images by the algorithm.This provide technical support for detect the biological tissue morphological structure,the physiological characteristics,the biochemical information and so on;Photoacoustic microscopy imaging is divided into optical and acoustic resolution,the former have high imaging resolution,but imaging depth be defined in 1 mm or so,the latter imaging resolution is lower than the former,but imaging depth is much larger than the former,it can reach the centimeter level.As a new type of nondestructive biomedical imaging,Photoacoustic imaging will make a great contribution to human health career.For the acoustical resolution photoacoustic medical microscopic imaging system,imaging depth,signal-to-noise ratio and imaging resolution is decision factors for imaging quality.This article mainly has carried on the following several aspects of research work.Firstly,built a set of acoustic resolution photoacoustic medical microscopic imaging system and simulation by optical software;secondly,design a kind of new type of condenser which can improve the imaging effect;puts forward the different way of lighting for the imaging effect;finally,design the imitation of body and animal to validate above suspect by the experiment.By the experimental tests,demonstrated the feasibility of the system.Known imaging depth and imaging resolution are contradictory and restraining each other.Imaging lateralresolution will increase with the increase of ultrasonic probe center frequency,but the imaging depth would reduce.Convex bottom condenser focus the light spot on smaller,its imaging signal-to-noise ratio is superior to the traditional flat condenser design.The method of bright field illumination is superior to the method of laser dark field illumination,bright field lighting helps to improve the SNR of the system and the imaging depth.