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由于光相干层析成像中测量的干涉信号空间频带有限 ,因此会产生散斑。在高散射的生物组织图像中 ,散斑具有双重身份 ,即作为噪声源和作为组织微结构的信号载体。本文的前半部分对于光相干层析成像中散斑的产生原因、统计特性以及分类作了综述。通过采样束的相位和振幅扰动可以定义信号载体散斑和信号降低散斑。本文的后半部分讨论了减少散斑的 4种方法 :偏振合成法、空间合成法、频率合成法和数字信号处理方法 ,并且通过举例对每一种方法的有效性作了简单的分析。最后 ,文章提出了需进一步研究的问题
Speckle speckles are generated due to the limited spatial band of interference signals measured in optical coherence tomography. Speckles have a dual identity in highly scattering biological tissue images, both as a source of noise and as a signal carrier for tissue microstructures. The first half of this paper reviews the causes, statistical characteristics and classification of speckle in optical coherence tomography. Signal carrier speckle and signal reduction speckle can be defined by the phase and amplitude perturbations of the sampled beam. In the second half of this paper, we discuss four methods to reduce speckle: polarization synthesis, space synthesis, frequency synthesis and digital signal processing. The validity of each method is briefly analyzed through examples. Finally, the article raises the questions for further study