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Agbana, T.E. (author), Yang, H. (author), Soloviev, O.A. (author), Vdovin, Gleb (author), Verhaegen, M.H.G. (author)This paper presents experimental results of a static aberration control algorithm based on the linear relation be- tween mean square of the aberration gradient and the second moment of point spread function for the generation of control signal input for a deformable mirror (DM). Results presented in the work of Yang et al.1 suggested a good...conference paper 2016
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Habets, Michel (author), Scholten, Joni (author), Weiland, Siep (author), Coene, W.M.J.M. (author)The imaging quality of the projection optics of an extreme ultraviolet lithography scanner degrades under the influence of thermally induced deformations of its mirrors. Wavefronts of different reticle points encounter different parts of the deformed mirrors, resulting in a field dependent wavefront error. This paper presents how ideas from...conference paper 2016
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Theulings, E.C.A.S. (author)Deformable mirrors are widely used in adaptive optics to correct wavefront aberrations. Actuators are used to deform the mirror into the shape that is needed for this correction. The most common type of actuation is with out-of-plane actuators that are placed on the backside of the mirror surface. Actuation with in-plane actuators placed on the...master thesis 2015
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Kant, N. (author)In this thesis a model-based filter is developed to improve the estimates of the lens aberrations.master thesis 2015
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Mulder, Y.T.B. (author), Romijn, J. (author), Verhaert, D.S.M. (author)In this project, a USB DAC was designed. This was done according to a proposal from Flexible Optical B.V. which is located in Rijswijk. This device is used to correct for atmospheric interference in optical measurement systems. The existing DAC is ten years old and needs to be updated to requirements of today. The 'next generation' DAC has been...bachelor thesis 2015
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Van Dam, L. (author), Van Dijk, S.A. (author), Van der Kaay, M.S. (author)A High-Speed Digital-to-Analog converter system is proposed that is controlled using USB 3.0. Possibilities to improve the refresh rate and resolution are researched to meet the standards of modern measurement systems. For instance, adaptive optics often uses a DAC in its feedback loop, but the USB DAC systems currently available provide...bachelor thesis 2015
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Yoo, H.W. (author)Confocal laser scanning microscopy (CLSM) is considered as one of the major advancements in microscopy in the last century and is widely accepted as a 3D fluorescence imaging tool for biological studies. For the emerging biological questions CLSM requires fast imaging to detect rapid biological processes and aberration-corrected imaging to...doctoral thesis 2015
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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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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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Vdovin, Gleb (author), Gong, H. (author), Soloviev, O.A. (author), Pozzi, P. (author), Verhaegen, M.H.G. (author)We have experimentally demonstrated a lensless coherent microscope based on direct registration of the complex optical field by sampling the pupil with a sequence of two-point interferometers formed by a digital micromirror device. Complete registration of the complex amplitude in the pupil of the imaging system, without any reference beam,...journal article 2015
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Antonello, J. (author)Microscopy is an essential tool for life sciences. Thanks to the development of confocal and multiphoton microscopy, scientists are able to obtain high-resolution 3D views of biological specimens. Nevertheless, spatial variations in the index of refraction within specimens cause aberrations that degrade the quality of the 3D views. One can...doctoral thesis 2014
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Korkiakoski, V.A. (author), Keller, C.U. (author), Doelman, N. (author), Kenworthy, M. (author), Otten, G. (author), Verhaegen, M.H.G. (author)We present two complementary algorithms suitable for using focal-plane measurements to control a wavefront corrector with an extremely high-spatial resolution. The algorithms use linear approximations to iteratively minimize the aberrations seen by the focal-plane camera. The first algorithm, Fast & Furious (FF), uses a weak-aberration...journal article 2014
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Lopes e Silva, J. (author)We are currently facing an increasing amount of challenges in the area of photonics as more and more applications in need for active “photon control” sprout in different fields of science. Adaptive Optics (AO) is the subject which deals with measuring, reconstructing, and reshaping the phase of a photon wavefront in real-time and can, thus,...master thesis 2014
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Antonello, J. (author), Van Werkhoven, T. (author), Verhaegen, M. (author), Truong, H.H. (author), Keller, C.U. (author), Gerritsen, H.C. (author)Optical aberrations have detrimental effects in multiphoton microscopy. These effects can be curtailed by implementing model-based wavefront sensorless adaptive optics, which only requires the addition of a wavefront shaping device, such as a deformable mirror (DM) to an existing microscope. The aberration correction is achieved by maximizing a...journal article 2014
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Van Werkhoven, T.I.M. (author), Antonello, J. (author), Truong, H.H. (author), Verhaegen, M. (author), Gerritsen, H.C. (author), Keller, C.U. (author)Deep imaging in turbid media such as biological tissue is challenging due to scattering and optical aberrations. Adaptive optics has the potential to compensate the tissue aberrations. We present a wavefront sensing scheme for multi-photon scanning microscopes using the pulsed, near-infrared light reflected back from the sample utilising...journal article 2014
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Ten Have, E.S. (author)This thesis investigates a novel deformable mirror that works on the basis of the electrostatic deformation of a liquid surface. The liquid mirror allows large surface displacements, a large number of actuators, and the modification of its properties, while at the same time the mirror design is simple and may be realized without sophisticated...doctoral thesis 2014
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Polo, A. (author)In the semiconductor industry, optical lithography is presently the most widespread technology used to print a geometrical pattern on a semiconductor wafer. Because of the plans imposed by the International Technology Roadmap for Semiconductors (ITRS) for more powerful and smaller chips, new printing technologies capable of printing smaller...doctoral thesis 2014
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Saathof, R. (author)In highly precise systems the thermal expansion of system-parts is of increasing concern, since it can severely compromise its performance at sub-nanometre level. An example of such a system is an Extreme UltraViolet (EUV)-lithography machine that is used in the semi-conductor industry to project the pattern of the chip onto a silicon wafer. In...doctoral thesis 2013
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Tesch, J. (author), Gibson, S. (author), Verhaegen, M. (author)A new method for adaptive prediction and correction of wavefront errors in adaptive optics (AO) is introduced. The new method is based on receding-horizon control design and an adaptive lattice filter. Experimental results presented illustrate the capability of the new adaptive controller to predict and correct aero-optical wavefronts derived...journal article 2013
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Ten Have, E.S. (author), Vdovin, G. (author)A deformable mirror based on the principle of total internal reflection of light from an electrostatically deformed liquid–air interface was realized and used to perform closed-loop adaptive optical (AO) correction on a collimated laser beam aberrated by a rotating phase disk. Equations describing the resonant and oscillatory behavior of the...journal article 2012