Dynamic correction of aberrations in microscopic imaging systems using an artificial point source
Dynamic correction of aberrations in microscopic imaging systems using an artificial point source
复制标题
使用人工点源动态校正显微成像系统中的像差
DOI：
10.1117/12.544115
复制
发表时间：
2004
影响因子：
1.5
通讯作者：
W. Osten
中科院分区：
文献类型：
--
作者：
M. Reicherter;W. Górski;T. Haist;W. Osten
在生物显微操作中，像差不仅由光学系统引入，而且由浸没液体引入。然而，光学系统像差是恒定的，并且相对容易测量和校正它们，而浸没引起的像差在时间和空间上是可变的。本文提出了一种利用球形微粒子作为人工点光源进行像差控制的方法。通过光学镊子将颗粒定位在生物样品的位置处。实验中使用了全息光镊。它们基于计算机生成的全息图，写入空间光调制器，在物平面上为微粒创建光陷阱。光阱可以移动，而不需要任何机械移动部件，只需改变全息图。粒子强烈地聚焦光，因此在对象空间中创建了人工点源。照明光被过滤，使得波前检测系统仅分析对应于球面波的信号。波前畸变的信息被用来动态校正，这可以通过使用空间光调制器来实现。该方法适用于生物光子成像系统，其中样品平面中的折射率变化是显着的。与全息镊子的集成是有利的，因为它提供了定位和成像颗粒的灵活性。
In biological micromanipulation image aberrations are introduced not only by the optical system, but also by the immersion liquid. Whereas optical system aberrations are constant and it is relatively easy to measure and correct for them, the immersion caused aberrations are variable in time and space. In this paper a method using a spherical microparticle as an artificial point source for aberration control is presented. The particle is positioned by optical tweezers at the location of the biological sample. In the experiment holographic tweezers are used. They are based on computer generated holograms, written into spatial light modulators, which create light traps for the microparticle in the object plane. The light traps can be moved without any mechanically moving parts, just by changing the hologram. The particle strongly focuses the light, therefore an artificial point source in the object space is created. The illumination light is filtered, so that only the signal corresponding to a spherical wave is analyzed by the wavefront detection system. The information about the wavefront distortion is used to dynamically correct for it. This can be done by using spatial light modulators. The method is suitable for biophotonic imaging systems, where refractive index variations in the sample plane are significant. The integration with holographic tweezers is advantageous since it offers flexibility in positioning and imaging the particles.