基于声光可调滤波器的肺癌组织快速显微光谱成像

Rapid Microscopic Spectral Imaging of Lung Cancer Tissue Based on Acousto-Optic Tunable Filter

相比于传统的分光元件,非共线声光可调滤波器(AOTF)具有小巧、稳定性强、调谐灵活快速、信号接收和处理方便等诸多优点,在光谱成像领域具有很高应用价值。将非共线AOTF与倒置光学显微镜有机结合,构建了显微光谱成像系统,在可见光范围内开展了肺癌组织的快速显微光谱成像研究。通过实验获得了加载在AOTF上的超声频率与衍射光波长的调谐关系,与理论计算结果符合较好;获得了在一系列中心光波长下的肺癌组织的显微图像和对应的窄带光谱。实验结果表明,系统在工作波段内均保持较好的光谱分辨性能;对不同光波长肺癌组织图像进行对比,结果未见图像明显漂移,表明图像稳定性高;各中心波长下获得的肺癌组织图像均呈现较好的清晰度;不同波长肺癌组织图像的对比以及亮度、透射率曲线的分析结果显示,在503.45~590.12nm范围内,肺癌组织图像呈现最佳的对比度和清晰度,这主要是源于不同区域的内在组分和结构不同使得肺癌组织对于不同波长光信号的吸收程度不同。

Compared with the traditional beam-splitting elements,the noncollinear acousto-optic tunable filter（AOTF）has many special merits,such as small size,high stability,flexible and easy to tune,convenient for signal reception and processing.It has high application value in spectral imaging field.In this study,the noncollinear AOTF is connected with the converted microscope,and a hyperspectral microscopy imaging system is built.With the system,the rapid microscopic spectral imaging for lung cancer tissue is studied in the visible range.In the experiments,the relationship between the acoustic frequency and the diffracted optical wavelength loaded on AOTF is got,and the theoretical results coincide well with the experimental data.A series of microscopy images and corresponding narrow band spectra of lung cancer tissue are received at central wavelength.The results indicate that the system keeps a well spectral resolution performance in the working waveband.By comparing the lung cancer tissue images under different wavelengths,it is found that obvious image drift is not observed,which indicates that the image has high stability.Lung cancer tissue images of each central wavelength all present good clarity.The comparison of lung cancer tissue image and the analysis results of luminance curve and transmissivity curve show that the best contrast and clarity performance of the images are in the range of 503.45-590.12 nm.It is mainly because the different intrinsic constituents and structures in different areas induce different absorptivities of the signals with different optical wavelengths in lung cancer tissues.