Jozef Stefan Institute, Complex Matter Department, Jamova 39, Ljubljana, Slovenia.
J Biomed Opt. 2009 Nov-Dec;14(6):064024. doi: 10.1117/1.3275465.
We present an experimental comparison of pulsed photothermal (PPT) profiling in collagen-based tissue phantoms utilizing different midinfrared spectral bands. Laser-induced temperature profiles are reconstructed using a custom optimization code within the customary monochromatic approximation. Both experimental results and a detailed numerical simulation of the procedure demonstrate that, despite the associated reduction of signal-to-noise ratio, appropriate spectral filtering reduces the broadening of temperature peaks and thus improves the accuracy of temperature profiling. For our experimental system, best performance is obtained when applying a long-pass filter with cut-on wavelength at 3.4-3.8 microm. Because our collagen gel mimics infrared and thermal properties of human skin, we believe that this conclusion is transferrable to PPT radiometric profiling of human skin in vivo.
我们在利用不同中红外光谱带的基于胶原蛋白的组织模型中进行了脉冲光热（PPT）剖面分析的实验比较。使用常规单色近似中的自定义优化代码来重建激光诱导的温度分布。实验结果和该过程的详细数值模拟都表明，尽管信号噪声比降低，但适当的光谱滤波可以减小温度峰值的展宽，从而提高温度剖面分析的准确性。对于我们的实验系统，当使用截止波长在 3.4-3.8 微米的长通滤波器时，可获得最佳性能。由于我们的胶原蛋白凝胶模拟了人体皮肤的红外和热特性，我们相信这个结论可以推广到人体皮肤的 PPT 辐射剖面分析中。
