| dc.description.abstract | This paper is inspired by research on the determination of the age of bruises. Over time, the concentration of substances inside bruises changes, making quantitative substance concentration an important part of predicting bruise age. The purpose of this study is to develop
a photoacoustic system, by selecting and possessing the absorption characteristics of the target, provides depth information and can quantify the concentration of the target substance.
To simulate human skin tissue, the experiment created gelatin-based phantoms embedded with capillaries tube and injected with red dye Ponceau 4R to simulate blood vessels and blood, respectively. A 532 nm laser was used as the excitation light source to excite the Ponceau 4R. By adjusting the substance inside the phantom and its thickness, the study measured the trend of photoacoustic signal intensity with changes in the volume percentage concentration of the dye under different conditions, discussing the limitations and issues of the constructed photoacoustic system in the experiment.
Furthermore, by repeatedly measuring the signal intensity variation of specific concentration ranges of the dye and performing linear fitting, a concentration quantification
model was established. Subsequently, the signal intensity of known random concentrations was measured using photoacoustics, and the results were plugged into the model to obtain concentration predictions. These predictions were compared with actual concentration values and discussed to establish the foundation for the quantitative function of this framework. Finally, goals for future development of the system were formulated based on the problems encountered during the research process. | en_US |