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Maddalena, L. (author), Pozzi, Paolo (author), Ceffa, Nicolò G. (author), Hoeven, Bas van der (author), Carroll, E.C.M. (author)Light-sheet microscopy is a powerful method for imaging small translucent samples in vivo, owing to its unique combination of fast imaging speeds, large field of view, and low phototoxicity. This chapter briefly reviews state-of-the-art technology for variations of light-sheet microscopy. We review recent examples of optogenetics in...book chapter 2023
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Tokovinin, A. (author), Thomas, S. (author), Vdovin, G. (author)Membrane micro-machined deformable mirrors (MMDM) feature low cost, low power consumption, small size and absence of hysteresis. Interested in using such a device for the adaptive optics system at the SOAR 4.1-m telescope, we evaluated the performance of a 79-channel 50-mm (pupil size 35mm) MMDM from OKO Technologies. The measured influence...conference paper 2004
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Vdovin, G. (author), Loktev, M. (author), Simonov, A. (author), Kiyko, V. (author), Volkov, S. (author)We designed and built an experimental setup for subjective (manually controlled) correction of up to 12 orthogonal terms (excluding tilts and defocus) of the aberration of the human eye. In our experiments, the subject was looking through an adaptive optical system at the USAF resolution chart. By using the arrow keys of the computer keyboard,...conference paper 2005
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Hinnen, K. (author), Doelman, N. (author), Verhaegen, M. (author)The problem of finding the closed-loop optimal controller is formulated in an H2-optimal control framework. This provides a natural way to account for the fact that in many AO systems the wavefront phase cannot be measured directly. Given a multi-variable disturbance model of both wavefront slopes and wavefront phases,3 this provides a general...conference paper 2005
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Ten Have, E.S. (author), Vdovin, G. (author)Closed-loop adaptive optical correction using a deformable mirror based on the total internal reflection (TIR) from an electrostatically deformed liquid-air interface was performed on a collimated beam of a HeNe-laser that was aberrated by a rotating phase disk. The frequency response of the system was measured and the influence of liquid...conference paper 2011
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Loktev, M. (author), Vdovin, G. (author), Soloviev, O. (author)We describe a compact integrated module implementing a low-cost adaptive optics system. It is targeted as a correction system for small telescopes with primary mirror diameter up to 1 m, operating on a natural guide star with magnitude at least 4 (for a 25 cm telescope). It is supposed to provide stable diffraction-limited imaging of stars,...conference paper 2008
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Hinnen, K. (author), Verhaegen, M. (author), Doelman, N. (author)Most adaptive optics systems (AO) are based on a simple control law that is unable to account for the temporal evolution of the wavefront. In this paper, a recently proposed data-driven H2-optimal control approach is demonstrated on an AO laboratory setup. The proposed control approach does not assume any form of decoupling and can therefore...conference paper 2006
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Doelman, N.J. (author), Hinnen, K.J.G. (author), Stoffelen, F.J.G. (author), Verhaegen, M.H. (author)An Adaptive Optics (AO) system for astronomy is analysed from a control point of view. The focus is put on the temporal error. The AO controller is identified as a feedback regulator system, operating in closed-loop with the aim of rejecting wavefront disturbances. Limitations on the performance of feedback regulator systems are discussed. The...conference paper 2004
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Vdovin, G. (author), De Lima Monteiro, D.W. (author), Akhzar-Mehr, O. (author), Loktev, M. (author), Sakarya, S. (author), Soloviev, O. (author), Sarro, P.M. (author)We present an overview of the results of our recent research in the field of adaptive optical components based on silicon microtechnologies, including membrane deformable mirrors, spatial light modulators, liquid-crystal correctors, wavefront sensors, and both spherical and aspherical micro-optical components. We aim at the realization of...conference paper 2004
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Hinnen, K. (author), Verhaegen, M. (author), Doelman, N. (author)Even though the wavefront distortion introduced by atmospheric turbulence is a dynamic process, its temporal evolution is usually neglected in the adaptive optics (AO) control design. Most AO control systems consider only the spatial correlation in a separate wavefront reconstruction step. By accounting for the temporal evolution of the...conference paper 2005
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Polo, A. (author), Bociort, F. (author), Pereira, S.F. (author), Urbach, H.P. (author)Accurate wavefront aberration measurement are essential for next-generation Extreme Ultraviolet (EUV) Lithography. During the past years several accurate interferometric techniques have been developed, but these techniques have limitation. In this work we discuss a different technique based on the Hartmann Wavefront Sensor that requires no...conference paper
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Agbana, T.E. (author), Soloviev, O. (author), Bezzubik, V. (author), Patlan, V. (author), Verhaegen, M. (author), Vdovin, G.V. (author)We have implemented an extended depth of field optical system by wavefront coding with a micromachined membrane deformable mirror. This approach provides a versatile extension to standard wavefront coding based on fixed phase mask. First experimental results validate the feasibility of the use of adaptive optics for variable depth wavefront...conference paper 2015
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Fraanje, R. (author), Doelman, N. (author)In recent years various researchers have proposed an optimal control approach for the rejection of turbulence-induced wavefront distortions in an AO system. The essential element in the design of an optimal controller is the choice for the turbulence model, which predicts the turbulence to compensate for the inherent delay in the AO control loop...conference paper 2010
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Song, H. (author), Simonov, A.N. (author), Vdovin, G. (author)Addressing of massive arrays of piezoelectric actuators is usually achieved by using separate high-voltage output drivers, one per channel. This approach applied to high-order adaptive optics systems results in complex, expensive and vulnerable to handling abuse driver electronics, hardly scalable to 103-104 actuators. To reduce the number of...conference paper 2005
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Piscaer, P.J. (author), Soloviev, O.A. (author), Verhaegen, M.H.G. (author)This paper discusses various practical problems arising in the design and simulation of predictive control methods for adaptive optics. Although there has been increased attention towards optimal prediction and control methods for AO systems, they are often tested in simplified simulation environments. The use of advanced AO simulators...conference paper 2020
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Soloviev, O.A. (author), Verhaegen, M.H.G. (author), Vdovin, Gleb (author)Shack-Hartmann (SH) sensor, based on sampling of wavefront tilts in subapertures, is a simple, reliable, and widely used in adaptive optics wavefront sensor. A wavefront curvature sensor has the advantage of providing the results suitable for direct control of membrane and bimorph deformable mirrors [1], but requires linear registration of...conference paper 2015
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Gong, H. (author), Pozzi, P. (author), Soloviev, O.A. (author), Verhaegen, M.H.G. (author), Vdovin, Gleb (author)We present a reference-less and time-multiplexing phase retrieval method by making use of the digital micromirror device (DMD). In this method, the DMD functions not only as a flexible binary mask which modulates the optical field, but also as a sampling mask for measuring corresponding phases, which makes the whole setup simple and robust. The...conference paper 2016
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Quintavalla, M. (author), Pozzi, P. (author), Verhaegen, M.H.G. (author), Bijlsma, H.K. (author), Verstraete, H.R.G.W. (author), Bonora, S. (author)Adaptive Optics (AO) has revealed as a very promising technique for high-resolution microscopy, where the presence of optical aberrations can easily compromise the image quality. Typical AO systems however, are almost impossible to implement on commercial microscopes. We propose a simple approach by using a Multi-actuator Adaptive Lens (MAL)...conference paper 2018
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Yoo, H.W. (author), van Royen, M.E. (author), van Cappellen, WA (author), Houtsmuller, AB (author), Verhaegen, M.H.G. (author), Schitter, G (author)The pinhole plays an important role in confocal laser scanning microscopy (CLSM) for adaptive optics (AO) as well as in imaging, where the size of the pinhole denotes a trade-off between out-of-focus rejection and wavefront distortion. This contribution proposes an AO system for a commercial CLSM with an adjustable square pinhole to cope with...conference paper 2016
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Verstraete, H.R.G.W. (author), Almasian, M. (author), Pozzi, P. (author), Bilderbeek, R (author), Kalkman, J. (author), Faber, DJ (author), Verhaegen, M.H.G. (author)In this manuscript, we present a lens setup for large defocus and astigmatism correction. A deformable defocus lens and two rotational cylindrical lenses are used to control the defocus and astigmatism. The setup is calibrated using a simple model that allows the calculation of the lens inputs so that a desired defocus and astigmatism are...conference paper 2016