Searched for: faculty:"Applied%5C%2BSciences"
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Mout, B.M. (author), Wick, M. (author), Bociort, F. (author), Urbach, H.P. (author)
The Wigner Distribution Function (WDF) forms an alternative representation of the optical field. It can be a valuable tool for understanding and classifying optical systems. Furthermore, it possesses properties that make it suitable for optical simulations: both the intensity and the angular spectrum can be easily obtained from the WDF and the...
conference paper 2015
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Hou, Z. (author), Bociort, F. (author)
A major challenge in lens design is the presence of many local minima in the optimization landscape. However, unlike other global optimization problems, the lens design landscape has an additional structure, that can facilitate the design process: many local minima are closely related to minima of simpler problems. For discussing this property,...
conference paper 2015
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Strauch, M. (author), Livshits, I.L. (author), Bociort, F. (author), Urbach, H.P. (author)
We show that wide-angle spectral imaging can be achieved with compact and cost-effective devices using Fabry-Pérot interferometers. Designs with a full field of view of 90°, in which the Fabry-Pérot interferometer is mounted either in front of an imaging lens system or behind a telecentric lens system, are presented and analysed. We show the...
journal article 2015
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Bociort, F. (author), van Grol, P. (author)
Understanding the structure of the design space in optical system optimization is difficult, because common human intuition fails when it encounters the challenge of high dimensionality, resulting from the many optimization parameters of lens systems. However, a deep mathematical idea, that critical points structure the properties of the space...
conference paper 2012
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Polo, A. (author), Kutchoukov, V. (author), Bociort, F. (author), Pereira, S.F. (author), Urbach, H.P. (author)
We apply a phase retrieval algorithm to the intensity pattern of a Hartmann wavefront sensor to measure with enhanced accuracy the phase structure of a Hartmann hole array. It is shown that the rms wavefront error achieved by phase reconstruction is one order of magnitude smaller than the one obtained from a typical centroid algorithm....
journal article 2012
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Mu, C. (author), Cornelissen, H.J. (author), Bociort, F. (author), Liebig, T. (author)
A new approach is described to couple light from high-power blue LEDs (1x1mm2) into a thin large area light guide using a dielectric interference multilayer as an angular filter. The goal is to achieve large area luminaires such as backlight systems. The method overcomes the drawback of structuring holes or recessions in light guides when using...
conference paper 2011
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Bociort, F. (author)
The presence of many local minima in the merit function landscape is perhaps the most difficult challenge in lens design. We present a simplified mathematical model that illustrates why the number of local minima increases rapidly with each additional lens added to the imaging system. Comparisons with results obtained with lens design software...
conference paper 2010
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Bociort, F. (author), Van Grol, P. (author)
In this paper we describe new properties of the design landscape that could lead in the future to a new way to determine good starting points for subsequent local optimization. While in optimization the focus is usually only on local minima, here we show that points selected in the vicinity of other types of critical points (i.e. points where...
conference paper 2010
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Bociort, F. (author), Van Grol, P. (author)
In this paper we describe new properties of the design landscape that could lead in the future to a new way to determine good starting points for subsequent local optimization. While in optimization the focus is usually only on local minima, here we show that points selected in the vicinity of other types of critical points (i.e. points where...
conference paper 2010
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Van Grol, P. (author), Bociort, F. (author), Van Turnhout, M. (author)
Contrary to the frequent tacit assumption that the local minima of a merit function are points scattered more or less randomly over the design landscape, we have found that, at least for simple imaging systems (doublets with three and triplets with five variables) all design shapes we have observed thus far form a strictly ordered set of points,...
conference paper 2009
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Bociort, F. (author), Van Turnhout, M. (author)
journal article 2009
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Van Turnhout, M. (author), Bociort, F. (author)
In lens design, damped least-squares methods are typically used to find the nearest local minimum to a starting configuration in the merit function landscape. In this paper, we explore the use of such a method for a purpose that goes beyond local optimization. The merit function barrier, which separates an unsatisfactory solution from a...
journal article 2009
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Van Turnhout, M. (author), Bociort, F. (author)
Many optical design programs use various forms of the damped least-squares method for local optimization. In this paper, we show that damped least-squares algorithms, with maximized computational speed, can create sensitivity with respect to changes in initial conditions. In such cases, starting points, which are very close to each other, lead...
journal article 2009
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Bociort, F. (author), Andersen, T.B. (author), Beckmann, L.H.J.F. (author)
We extend the method for the automatic computation of high-order optical aberration coefficients to include (1) a finite object distance and (2) an infinite entrance pupil position (telecentricity in object space). We present coefficients of the power series expansion of the transverse aberration vector with respect to the normalized aperture...
journal article 2008
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Marinescu, O. (author), Bociort, F. (author)
journal article 2008
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Marinescu, O. (author), Bociort, F. (author)
journal article 2008
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Marinescu, O. (author), Bociort, F. (author)
journal article 2008
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Marinescu, O. (author), Bociort, F. (author)
The merit function space of mirror system for extreme ultraviolet (EUV) lithography is studied. Local minima situated in the multidimensional optical merit function space are connected via links that contain saddle points and form a network. We present networks for EUV lithographic objective designs and discuss how these networks change when...
journal article 2007
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Bociort, F. (author), Van Turnhout, M. (author), Marinescu, O. (author)
Saddle-point construction (SPC) is a new method to insert lenses into an existing design. With SPC, by inserting and extracting lenses new system shapes can be obtained very rapidly, and we believe that, if added to the optical designer’s arsenal, this new tool can significantly increase design productivity in certain situations. Despite the...
conference paper 2007
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Van Turnhout, M. (author), Bociort, F. (author)
Local optimization algorithms, when they are optimized only for speed, have in certain situations an unpredictable behavior: starting points very close to each other lead after optimization to different minima. In these cases, the sets of points, which, when chosen as starting points for local optimization, lead to the same minimum (the so...
conference paper 2007
Searched for: faculty:"Applied%5C%2BSciences"
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