【摘要】 将菲涅耳波带板扫描全息术用于高散射介质成像技术中。对于编码函数非负给物体的再现像带来的背景噪音 ,提出采用构造复合全息图的方法来消除。在实验中运用该方法得到了信噪比和衬比度较好的物体的再现像。计算并测试了系统的点扩展函数 ,实验结果与理论计算结果相吻合 ,其结果都接近于二维的δ函数。用菲涅耳波带板扫描全息成像系统进行了成像实验 ,得到了嵌埋在浓度为 1%、深度为 1.7cm的脂肪乳剂中的吸收体清晰的再现像 ,吸收体为直径 0 .4mm的金属丝和内径为 6 .0mm的金属环 ,另外 ,也得到了直径为 2 .5mm的黑塑料球的再现像。更多还原

【Abstract】 The Fresnel zone plate scanning holography is applied in the imaging through highly scattering media. The background noise of the reconstructed image is resulted from the nonnegative coded function. A method of constructing composite hologram for reducing the background noise is proposed. The reconstructions with good-quality signal-to-noise ratio (SNR) and contrast ratio are obtained in experiments using this method. The system point spread function (PSF) is designed to be similar to the Dirac delta function. The experimental results and the theoretical calculation of the PSF are in accordance. The experiments on absorbers embedded in the intralipid solution with concentration of 1% and depth of 1.7 cm are implemented. The results demonstrate that the reconstructions of the metal ring with diameter of 6.0 mm and the metal wire with diameter of 0.4 mm are clear. The reconstruction of the black plastic ball with diameter of 2.5 mm is also satisfied.更多还原