An optical tomography PSF almost insensitive to aberrations: the benefit of a spatial incoherent illumination (Conference Presentation)
An optical tomography PSF almost insensitive to aberrations: the benefit of a spatial incoherent illumination (Conference Presentation)
复制标题
光学断层扫描 PSF 对像差几乎不敏感：空间不相干照明的好处（会议演示）
DOI：
10.1117/12.2210950
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
A. Boccara
中科院分区：
文献类型：
--
作者：
P. Xiao;M. Fink;A. Boccara
拓宽了像差成像系统PSF；这种扩大是造成图像模糊的原因。为了纠正像差对眼科检查或生物样品的OCT图像的影响，已经进行了大量的努力。我们已经量化了几何像差对全景OCT图像的影响，发现除了信号电平降低外，大多数情况下没有分辨率损失。这显然就是为什么我们使用这些信号作为度量来校正波前畸变的原因。此外，我们发现这种模糊的缺失，这是由于我们记录了衍射限制参考信号和扭曲样本信号的点积，这是特定于使用非相干照明的，并且没有显示使用空间相干源的OCT方法。更准确地说，信号的损失大致与施特雷尔比的平方根成正比：例如，施特雷尔比为1/9，被认为是低质量的图像，在保持图像清晰度的情况下，在全场OCT中仅为1/3。使用这两个美国空军分辨率目标和透射SLM，我们已经证明了这种独特的特征的清晰度保护。生物样本也证实了这一点。因此，我们认为我们可以将眼科检查中的像差校正限制在主要像差（例如焦点和散光）上，从而提高校正速度。
An aberrated imaging system PSF is broadened; this broadening is responsible of the blurring of the images. A lot of effort has been carried out to correct the effects of aberrations on OCT images for eye examination or biological samples. We have worked on quantifying the effect of geometrical aberrations on Full-Field OCT images and found that there is mostly no loss of resolution but a decrease of the signal level. This is obviously why we use these signals as metric to correct the wavefront distortion. Moreover we found that this absence of blurring, which is due to the fact that we record the dot product of a diffraction limited reference signal and the distorted sample signal, is specific to the use of an incoherent illumination and did not show up with OCT approaches that use spatially coherent sources. More precisely the loss in signal is roughly proportional to the square root of the Strehl ratio: for example, a Strehl ratio of 1/9, which is considered to give a low quality image, would only be 1/3 in Full-Field OCT while keeping the sharpness of the image. Using both an USAF resolution target and a transmissive SLM we have demonstrated this unique feature of sharpness conservation. It was also confirmed by using biological samples. We think that we can thus restrict the aberration corrections in eye examination to the main aberrations (e.g. focus and astigmatism) that will increase the speed of the correction.