Adaptive optics for optical scanning microscopy

Project H.W. Yoo, MSc (Hans), G. Schitter (Georg), M. Verhaegen (Michel)
Keywords:Optics and imaging, Fluorescence optical microscopy, Optimization-based control, Identification and estimation
Sponsored by:STW

Figure 1. Biological confocal microscope, Leica SP5, in adaptive optics lab, TUDelft

This Ph.D. project is a part of the Integrated Smart Microscopy (ISM) project, a multidisciplinary project collaborated with multiple academical and industrial groups. The industrial partner are Flexible Optical BV (also known as OKO technologies), Scientific Volume Imaging BV, and Leica Microsystems BV. The academic partners are Delft University of Technology and Erasmus MC.

The ISM project aims to develop an integrated smart confocal microscope for live cell imaging, which combines adaptive optics in the imaging path with adaptive postprocessing of the resulting 3D image data. Objective of this PhD project is to integrate prediction and control design methodologies in optimizing the overall performance of the new microscope system, in terms of resolution as well as product complexity and costs. In addition to investigating the optimal size, location of the type of sensors and actuators, we also aim to achieve higher overall imaging performance by optimizing the tradeoff between feedback and postprocessing.

During the past few decades, the optical microscopy techniques have achieved significant improvements in terms of spatial resolutions. For the most biological samples, however, even the diffraction limited resolution is hardly obtained due to various aberrations due to misalignment in microscope and sample induced aberrations. In this regards, adaptive optics, which actively compensate for wavefront distortions as has been demonstrated in high-end telescopes, has recently attracted much attention as a promising approach to obtain near diffraction limited performance in the above mentioned applications.

Figure: PSF (x-z slice) of a lens with NA = 1.3 without spherical aberration (left) and when
imaging in a medium with refractive index 1.4 at a depth of 10um(right). Courtesy SVI (Huygens
software). From ISM project proposal.

At DCSC, various methodologies have been investigated to correct aberrations in various optical systems such as telescope and microscopes.[1,2] As an extension, fast and robust adaptive optics systems for commercial confocal microscopy are developed to achieve a real time sharp image over a wide field of view.


[1] K. Hinnen, M. Verhaegen, and N. Doelman, “A Data-Driven 2-Optimal Control Approach for Adaptive Optics”, IEEE Trans on Cont Sys. Tech., Vol. 16, No. 3, 381-395, 2008

[2] H. Song, R. Fraanje, G.Schitter, H. Kroese, G. Vdovin and M. Verhaegen, “Modelbased aberration correction in a closed-loop wavefront sensorless AO system”, Opt.
18, 24070-24084m 2010.

© Copyright Delft Center for Systems and Control, Delft University of Technology, 2017.