【摘要】 针对在成像物体没有超出散射介质记忆效应范围的情况下,提出一种结合数字离轴全息术减少散射介质成像中散斑自相关噪声的方法。当成像目标经过散射介质时,使用自相关技术结合相位恢复算法能够从散斑中重建成像目标。但在实际成像的过程中,为了有效抑制环境噪声和热噪声等对重建效果的影响,设计利用离轴全息中的相移法消除噪声项中静态噪声项的干扰,再利用散斑自相关与相位恢复算法重建去噪后效果更好的成像目标。采用结构相似度对重建效果进行定量评估,仿真结果表明对于给出的成像目标,去噪前后的结构相似度从0.879 6提高到0.987 5,验证了该方法的有效性。说明所提出的方法能够改善散斑自相关法重建效果。更多还原

【Abstract】 Aiming at the condition that the imaging object does not exceed the memory effect range of the scattering medium, a method combining digital off-axis holography to reduce the speckle autocorrelation noise in the imaging of the scattering medium was proposed. When the imaging target passed through the scattering medium, the autocorrelation technique combined with the phase recovery algorithm could reconstruct the imaging target from the speckle. However, in the actual imaging process, in order to effectively suppress the influence of environmental noise and thermal noise on the reconstruction effect, the design used the phase shift method in off-axis holography to eliminate the interference of the static noise item in the noise item, and then used the speckle autocorrelation and the phase recovery algorithm reconstructed the imaging target with better effect after denoising. The structural similarity was used to quantitatively evaluate the reconstruction effect.The simulation results show that for the given imaging target, the structural similarity before and after denoising increases from 0.879 6 to 0.987 5, which verifies the effectiveness of the method. It shows that the proposed method can improve the reconstruction effect of speckle autocorrelation method.更多还原