组建了具有980 nm和1300 nm两个波长光源的光学相干层析(OCT)成像系统。利用此系统,分别在两个波长、不同光源功率下,对新鲜猪肉组织进行OCT成像。比较了同一波长、不同功率和不同波长、同一功率下的OCT图像,并比较了同一波长、不同功率和不同波长、同一功率下OCT信号强度随深度变化的曲线。对曲线进行线性拟合,分析了两个波长下生物组织散射系数的变化规律。发现提高光源功率会使探测深度有限提高,而探测深度会随波长增大而增加,并分析了波长变化对OCT系统各参数的影响和进行对比的图像产生差异的原因。

An optical coherence tomography (OCT) system with two low coherence sources emitting at 980 nm and 1300 nm is set up. Using this system,we acquire the OCT images of fresh pork at two wavelengths and different source powers respectively. We compare the images obtained at one wavelength with different source power and at two wavelengths with same source power. The corresponding curves of OCT signals versus detection depth are also discussed. The scattering coefficient change of the tissue with the light emitting at two different wavelengths is analyzed by fitting the curve. Results show that the increase of the source power can finitely improve the probe depth and the increase of the source wavelength can improve the probe depth remarkably. The influence of wavelength on parameters of OCT system and the reason for differences between images are also discussed.