Adaptive aberration correction in a confocal microscope
Adaptive aberration correction in a confocal microscope
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DOI：
10.1073/pnas.082544799
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发表时间：
2002-04-30
影响因子：
11.1
通讯作者：
Wilson, T
中科院分区：
文献类型：
--
作者：
Booth, MJ;Neil, MAA;Wilson, T
与传统显微镜相比，共焦显微镜的主要优势是能够对厚样品进行光学“切片”；由此获得的薄图像切片可用于重建三维图像，这一能力在生物应用中特别有用。然而，众所周知，系统或样品诱导的像差会严重降低分辨率和光学切片能力。大口径镜头的使用进一步加剧了这一问题。此外，像差可以大大减少到达探测器的光子数量，从而导致对比度较低。因此，相当不幸的是，在实用显微镜中，很少实现无像差的共聚焦成像。自适应光学系统已被广泛用于校正天文学中的像差，它在这方面提供了解决方案，但也提出了新的挑战。共焦显微镜的光学系统和像差源有很大的不同，需要一种新的波前传感方法。该方法基于Zernike像差模式的直接测量，也显示出类似于共焦显微镜的轴向选择性。我们展示了一种自适应共聚焦荧光显微镜，它将这种模式传感器与可变形的膜镜结合在一起，用于像差校正。生物样品的像差校正图像在对比度和轴向分辨率的明显恢复方面有了很大的改善。
The main advantage of confocal microscopes over their conventional counterparts is their ability to optically "section" thick specimens; the thin image slices thus obtained can be used to reconstruct three-dimensional images, a capability which is particularly useful in biological applications. However, it is well known that the resolution and optical sectioning ability can be severely degraded by system or specimen-induced aberrations. The use of high aperture lenses further exacerbates the problem. Moreover, aberrations can considerably reduce the number of photons that reach the detector, leading to lower contrast. It is rather unfortunate, therefore, that in practical microscopy, aberration-free confocal imaging is rarely achieved. Adaptive optics systems, which have been used widely to correct aberrations in astronomy, offer a solution here but also present new challenges. The optical system and the source of aberrations in a confocal microscope are considerably different and require a novel approach to wavefront sensing. This method, based upon direct measurement of Zernike aberration modes, also exhibits an axial selectivity similar to that of a confocal microscope. We demonstrate an adaptive confocal fluorescence microscope incorporating this modal sensor together with a deformable membrane mirror for aberration correction. Aberration corrected images of biological specimens show considerable improvement in contrast and apparent restoration of axial resolution.