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The production of optical free-form surfaces requires a high level of precision and surface quality. The process chain presented combines pre-grinding, fine grinding and ultra-fine grinding using a 5-axis CNC machine in order to achieve high shape accuracy and surface quality. The presented process chain makes it possible to produce free-form surfaces with high geometric precision and optical qualities.

Deep neural networks have become a cornerstone of modern artificial intelligence applications, yet their decision-making processes often remainopaque. In this publication, the integration of explainable AI (XAI) techniquesinto the manufacturing processes of the optical and glass-processing industry isexplored. The work addresses the correlation between sensor-derived process data and the resulting quality of manufactured components using both classical and deep learning models. The need for transparency and interpretabilityis highlighted, especially in industrial contexts where human operators must understand and trust the system’s output to make informed decisions. The pro-posed approach allows for proactive identification of influencing error factors, paving the way for optimized process control and quality assurance.

Filter-based spectral systems are highly competitive due to their compactness, simplicity, and well-defined spectral characteristics. However, their primary drawback remains low detection efficiency. This work explores various strategies to enhance detection efficiency. While an additional row of beamsplitters can significantly improve illumination, alternative folded beam path designs—eliminating the need for beamsplitters—prove to be far more effective. Additionally, a novel approach utilizing a freeform mirror is introduced, enabling differential adjustment of detection efficiency across different spectral regions. For the first time, a comprehensive comparison of these strategies is presented.

In the field of optical manufacturing, fused silica has a high and constantly growing application potential. Its material advantages, such as low thermal expansion and high thermal shock resistance, as well as its high transparency from the ultraviolet to the infrared spectral range, result in a large number of application fields. For example, manufacturing processes in semiconductor technology require high-quality quartz materials throughout the wafer handling process to avoid non-permissible contamination and to withstand the high process temperatures. Another example are monolithic components for fiber preform manufacturing, where internal contours with high aspect ratios (e.g. component length to component diameter) and high surface qualities are required to draw fiber types with special properties. The demands on the complexity and accuracy of these components are constantly increasing, which is accompanied by the need to analyse and optimize modern CNC manufacturing techniques more and more. In the following, investigations on the grinding of internal contours with a high aspect ratio are presented, in which the influence of an ultrasonic assistance as well as different machining strategies are considered.

The presented investigations build on the results already presented at EOSAM 2022 on the in-situ monitoring of grinding processes, in which high correlations between vibrometry, force and topography data of machined fused silica samples could already be proven. With the help of new measurement setups, it was possible to also detect high-frequency vibration components in CNC grinding processes and to check their effects on the resulting surface qualities. The investigations were carried out on a 5-axis CNC machine and monitored with the help of vibrometric and white-light interferometric measurement technology. The aim was to look at the influences of process-side parameters on the process vibrations and the resulting surface qualities.

The presented investigations deal with real-time evaluation and recording of vibrations and forces during a CNC grinding process, as well as the analysis and control of process influences on the surface quality of optical components. The experiments were carried out on a 5-axis CNC machine. Rapid subsequent analysis of the topography resulting from grinding is achieved with the aid of white light interferometry. The aim of the investigations is to reduce the surface deviations (roughness, mid-spatials, waviness) influenced by process factors. It is shown that the vibration data measured during the grinding process correlate to a high degree with the recorded topography data.

The material fused silica, as well as other brittle-hard materials such as glass ceramics, have great potential for use in a wide range of applications due to their special material properties. The technical advantages of these materials require sophisticated processing technologies, including polishing steps, in order to be able to use these interesting materials advantageously. In addition, a current trend in modern optical manufacturing is the use of free-form surfaces and monolithic components that combine several optical and mechanical functions in one part. Novel or improved processes are needed in order to meet future requirements for resource-saving and effective production methods at the same time.

The presented investigations deal with the real-time evaluation and recording of vibrations and forces during a CNC grinding process as well as the analysis and control of process influences on the surface quality of optical components. The experiments were performed on a 5-axis CNC machine and monitored using a laser vibrometer and a dynamometer. The subsequent examination of the component surfaces and topographies is carried out with the aid of two white light interferometry systems (macroscopic and microscopic). The aim of the investigations is to record and analyze correlations between the vibrometry, force and topography measurement data in order to examine their influence on the grinding process and the resulting component quality and to examine whether in-process vibrometry and force measurements can be used to detect and predict component quality during the process. Furthermore, the influence of individual grinding parameters on the grinding forces as well as the resulting component qualities are investigated under consideration of the surface roughness. It is shown that the vibration and force data measured during the grinding process correlate to a high degree with the recorded topography data. In addition, it was possible to determine which parameters have a significant influence on the observed CNC process. The setting parameters feed speed, tool grain size, and infeed depth had the greatest influence on the roughness and also on the forces. For example, the roughness could be reduced by around 47% by using the lowest considered feed speed compared to the highest. Furthermore, the forces were significantly influenced by the ultrasonic and could be reduced by around 53% by switching it on. The results underline the importance of real-time measurement technologies for improving CNC grinding processes, as they provide critical insights into the dynamic behavior of the system and its impact on the surface quality of optical components. This research demonstrates that by understanding the correlation between process forces, vibrations, and resulting surface topographies, it is possible to develop predictive models for in-process quality assurance. Consequently, the findings pave the way for more efficient and reliable grinding processes, reducing rework rates, and production costs. The presented approach can be directly applied in high-precision manufacturing environments, contributing to advancements in the fabrication of high-quality optical systems.

Sodium vanadium phosphate Na3V2(PO4)3 (NVP) is a promising next‐generation cathode material for sodium‐ion batteries (SIB) but the practical application as a cathode active material for SIBs is hindered by its poor electronic conductivity. To overcome this limitation and to improve the electrochemical performance in terms of rate capability and cycling stability, carbon coatings are a viable approach. In this work, we utilized a spray‐drying synthesis process and systematically varied the processing parameters to optimize the electrochemical performance of NVP/carbon composite materials. The spray‐drying process yields spherical, porous granules of NVP particles embedded in a carbon matrix, which is formed by the thermal decomposition of polyacrylic acid or β‐lactose. Hierarchically structured Na3V2(PO4)3/carbon composite materials are synthesized via a spray‐drying process. By systematically varying the processing parameters such as the calcination temperature and atmosphere, carbon content and ball‐milling parameters, the morphology and microstructure of the composite can be adjusted, which finally yields optimized electrochemical performance.

•A comprehensive screening method using LC-QTOF-MS for forensic casework is presented.•The applicability is demonstrated by analyzing 259 authentic serum samples.•950 compounds were detected and correlated with their drug serum concentrations.•Compared to GC–MS, 240% (335 versus 141) more drugs were identified in serum samples. Comprehensive screening procedures for psychoactive agents in body fluids are an essential task in clinical and forensic toxicology. With the continuous emergence and adaption of new psychoactive substances (NPS) keeping a screening method up to date is challenging. To meet these demands, hyphenated high-resolution mass spectrometry has gained interest as extensive and expandable screening approach. Here we present a comprehensive method for systematic toxicological analysis of serum by liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) with data independent acquisition. The potential of this method was demonstrated by analysis of 247 authentic serum- and 12 post-mortem femoral blood samples. Thus 950 compounds, comprising 185 different drugs and metabolites could be identified. For the detected substances, including pharmaceutical substances, illicit drugs as well as NPS, serum concentrations were confirmed ranging from traces to toxic values indicating the capability for forensic toxicological requirements. Positive identification of drugs was achieved by accurate mass measurement (±5ppm for [M+H]+; ±10ppm for [M−H]−), retention time (±0.35min), isotopic pattern match (less than 10 m/z RMS [ppm]), isotope match intensity (less than 20% RMS) and the presence of at least two fragment ions. The LC-QTOF-MS procedure was shown to be superior to serum screening by GC–MS, since 240% (335 versus 141) more drugs were identified in serum samples compared to GC–MS.