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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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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
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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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Bociort, F. (author), Van Turnhout, M. (author), Marinescu, O.E. (author)Optimization of a projection system is performed to obtain a starting configuration that is at a local minimum of the merit function or simply a previously known minimum system is used as the starting configuration. A zero-thickness meniscus lens is inserted at a surface in the local minimum starting configuration with N surfaces to construct a...patent 2007
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Bociort, F. (author), Van Turnhout, M. (author)In present-day optical system design, it is tacitly assumed that local minima are points in the merit function landscapewithout relationships between them. We will show however that there is a certain degree of order in the design landscapeand that this order is best observed when we change the dimensionality of the optimization problem and when...conference paper 2006
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Marinescu, O. (author), Bociort, F. (author)Optical designers often insert or split lenses in existing designs. Here, we present, with examples from Deep and Extreme UV lithography, an alternative method that consists of constructing saddle points and obtaining new local minima from them. The method is remarkable simple and can therefore be easily integrated with the traditional design...conference paper 2006
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Bociort, F. (author), Van Turnhout, M. (author)Poster presentation Optics Research Group TU Delft in cooperation with STW The presence of multiple local minima in the merit function landscape is one of the main difficulties in optical system design, especially for systems with many variables. By considering saddle points, we find a certain degree of order in the design landscape that...journal article 2006
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Marinescu, O. (author), Bociort, F. (author)Optical designers often insert or split lenses in existing designs. Here, we present, with examples from Deep and Extreme UV lithography, an alternative method that consists of constructing saddle points and obtaining new local minima from them. The method is remarkable simple and can therefore be easily integrated with the traditional design...conference paper 2006
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Marinescu, O. (author), Bociort, F. (author)The multidimensional merit function space of complex optical systems contains a large number of local minima that are connected via links that contain saddle points. In this work, we illustrate a method to construct such saddle points with examples of deep UV objectives and extreme UV mirror systems for lithography. The central idea of our...conference paper 2005
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Bociort, F. (author), Van Turnhout, M. (author)Finding multiple local minima in the merit function landscape of optical system optimization is a difficult task, especially for complex designs that have a large number of variables. We discuss here a method that enables a rapid generation of new local minima for optical systems of arbitrary complexity. We have recently shown that saddle points...conference paper 2005
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Marinescu, O. (author), Bociort, F. (author)The merit function space of mirror systems for EUV lithography is studied. Local minima situated in a multidimensional merit function space are connected via links that contain saddle points and form a network. In this work we present the first networks for EUV lithographic objectives and discuss how these networks change when control parameters...conference paper 2005
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Serebriakov, A. (author), Bociort, F. (author), Braat, J. (author)In the year 2001 it was reported that the birefringence induced by spatial dispersion (BISD), sometimes also called intrinsic birefringence, had been measured and calculated for fluorides CaF2 and BaF2 in the deep UV range. It was also shown that the magnitude of the BISD in these cubic crystals is sufficiently large to cause serious problems...conference paper 2005
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Marinescu, O.E. (author), Bociort, F. (author), Braat, J.J.M. (author)Poster presentation Optics Research Group TU Delft in cooperation with ASM Lithograpy and TNOjournal article 2005
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Braat, J.J.M. (author), Marinescu, O.E. (author), Bociort, F. (author)Poster presentation Optics Research Group TU Delft in cooperation with ASM Lithograpy and TNOjournal article 2005
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Bociort, F. (author), Marinescu, O.E. (author)Poster presentation Optics Research Group TU Delft in cooperation with ASM Lithograpy and TNOjournal article 2005
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Marinescu, O. (author), Bociort, F. (author), Braat, J. (author)When Extreme Ultraviolet mirror systems having several high-order aspheric surfaces are optimized, the configurations often enter into highly unstable regions of the parameter space. Small changes of system parameters lead then to large changes in ray paths, and therefore optimization algorithms crash because certain sssumptions upon which they...conference paper 2004