| Zugriffsnummer | 54541 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Comparison of two fit algorithms to find the maximum of a simulated confocal intensity curve |
| Autor(in); Institution |
Wyss, Silvana; 5.1, Oberflächenmesstechnik, PTB-Braunschweig
Wurm, Martin; 4.2, Bild- und Wellenoptik, PTB-Braunschweig
Fu, Liwei; Institut für Technische Optik, Universität Stuttgart, Germany
Reichelt, Stephan; Institut für Technische Optik, Universität Stuttgart, Germany
|
| Quelle/Jahr | Modeling Aspects in Optical Metrology X:(2025), 1 - 7 |
| Artikelnummer | 135680Y |
| Schriftenreihe | Proceedings of SPIE: 13568 |
| ISSN | 0277-786X |
| DOI | |
| Verlag | Bellingham, Wash.: SPIE |
| Konferenzangaben | SPIE optical metrology 2025, Munich, 23-26, Juni, 2025, Germany |
| Freie Schlagworte | Confocal mircrosocpe ; Polynomial fit ; Gaussian fit ; Fourier optics ; BEM |
| Zusammenfassung | A model of a confocal microscope was created. The model applies the Boundary Element Method (BEM) to solve Maxwells equations numerically for the interaction of the light with the object under test, and a Fourier optics based implementation for the imaging process of the microscope, i.e. the propagation of the reflected or diffracted light to the image detector. The BEM is implemented in the software SpeckleSim provided by the ITO of the University of Stuttgart. The model is used to simulate a z-scan for each x-position of a line structure. To determine the height of the surface from the simulated intensities of the z-scan, the maximum of this intensity curve must be determined. The maximum can be found using different fit algorithms. Since the simulation is computing time intensive, the simulation contains less intensity values, than the measurement with a confocal microscope. Due to the different number of available intensity values, the optimum fit algorithms may differ. The Gaussian function and the third degree polynomial are analyzed as fit algorithms for the intensity curves resulting from the simulation. The two fit algorithms are evaluated using an information criterion. In addition, the effects of the fit algorithms on the height determination of a rectangular line structure are analyzed. The first results of this comparison of the two fit algorithms applied to the simulated z-scan intensity curve are presented. |
