We developed a precise ray-tracing simulation method from a pointset of aspheric lens surfaces measured by a 3D profilometer. This technique evaluates optical functionality of actual lenses considering form errors in the fabrication process. An anisotropic scaling sparse low-degree implicit (SLIM) technique is proposed for surface mesh reconstruction from measured points. Nagata patch is adopted for representing lens geometry including surface profile errors. In this study, the accuracy of fabricated lens surfaces generated by anisotropic scaling SLIM was assessed.

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Fixed abrasive lapping using diamond pellets (DP) is an effective method of lapping optical glass, sapphire, etc. Many DP lapping methods use a lapping platen, in which many DP are pasted with a regular layout. Moreover, the DP layout method affects the flatness of the workpiece. We have developed a computational DP lapping simulation including optimization of DP layout method. This paper presents an evaluation of the effectiveness of our development simulation through a series of experiments from the viewpoint of changes in the workpiece surface profile. In addition, the surface roughness of the workpiece was also evaluated. The results indicated that the actual workpiece surface profiles showed the same tendency as the computational results using both the conventional DP layout and optimization of DP layout with progress of lapping time. Furthermore, the surface roughness was not affected by optimization of the DP layout.

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Data mining methods were used to support decisions regarding reasonable cutting conditions. The aim of our research was to extract new knowledge by applying data mining techniques to a tool catalog. We used both hierarchical and non-hierarchical clustering of catalog data and also used applied multiple regression analysis. We focused on the shape element of catalog data and visually grouped end mills from the viewpoint of tool shape, which here meant the ratio of dimensions, using the k-means method. We then decreased the number of variables using hierarchical cluster analysis. We also found an expression for calculating the best cutting conditions, and we compared the calculated values with the catalog values.

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This study investigated adhesion of coatings on grinding surfaces. The grinding wheel grain size was #230 to #1500 and rapping chips were added. PVD coatings used were TiAlN , TiSiN, and CrSiN. A total of 12 chips were used in the cutting tests. Cutting resistance, tool wear, and cut surfaces were checked. The results indicated that the ideal grinding surface roughness was different between areas close to the edge and the rake surface. Areas close to the edge required a small surface to keep sharply. However, the rake surface did not require a small surface to reduce cutting resistance.

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