为了分析在不同激发波长下不同组织/目标光声信号的时域与频域特点和差异,根据光声信号产生的基本原理,采用光声信号时域和频域分析方法,设计了石墨仿体和离体组织等不同样品的多光谱光声实验。结果表明,样品的光声信号在时域与频域所展示的性能有很大的不同,不同样品的光声信号的声谱是不同的,且在不同激发波长下的声谱的峰值所对应的频率均相同,因而可以用于组织特性的描述、组分识别等用途。此研究有助于利用光声成像实现组织识别,并为进一步利用频谱分析方法研究多光谱光声成像奠定了基础。
In order to analysis the characteristics and differences of photoacoustic imaging signal under different wavelengths in time domain and frequency domain, multi-wavelength photoacoustic imaging experiment with different targets including graphite phantom, pork and pig blood phantom was designed. The results show that the performance of different targets was quite different in time domain and frequency domain. The acoustic spectrum of photoacoustic signals for different targets was unique. Frequencies corresponded to the peaks of acoustic spectrum were same. The performance can be utilized for tissue characterization description and component identification. The research is helpful for organizational recognization by using photoacoustic imaging. And it will be the fundamental research for further frequency-domain analysis and study of multispectral photoacoustic imaging.