How image processing know-how can deliver value-added for industry and biomedicine
The experts at SQB certainly know a thing or two about industrial image processing, having developed a new image processing system that opens up new options for using images in mechanical engineering and machine construction, as well as biological and medical applications.
For their research and development project – MINIMIZE (an acronym in German for “miniaturized, , multispectral, real-time image processing system”) – the Steinbeis experts in Ilmenau have developed a number of new concepts for systems capable of capturing spatially and multispectrally resolved image data at video frequencies. This data includes selected spectral bands for use in industrial and biomedical applications. For their project, it was also important to consider and include broadband illumination, adapted optics, a spatially and multispectrally resolving sensor module, electronic components, modeling features, and algorithms.
Looking at image scenes through technical eyes
Capturing, processing, and evaluating images with both spatial resolution and multispectral properties is the logical, methodical, and technical next step for “technical eyes”. These days, almost all cameras have three spectrally selective filters for capturing spatially resolved color images. Within the foreseeable future, numerous spectrally selective filters will be applied for spatially resolved spectral imaging. Development work carried out under the MINIMIZE project has allowed the team headed by Steinbeis entrepreneur Steffen Lübbecke to gain key scientific insights into applications and facilitate a breakthrough in how the technology is put to use. “It’s important that German industry and certain small and medium-sized enterprises and research institutions are given further support as flagships of photonic metrology and quality assurance,” says Steffen Lübbecke.
A holistic view of the underlying concept
To illuminate an area selected for imaging, a special broadband LED illumination unit was developed using near-infrared fluorophores. This unit helps compensate for the missing emission wavelengths of commercially available standard LED illumination. Due to its low energy requirements, the illumination unit can be embedded directly into the system designed to capture spatially and spectrally resolved images of skin surfaces. To capture imaging information on the sensor module that is spatially and multispectrally resolving, the partners in the project developed a special miniature, interchangeable optics system. Based on an apochromatic design and telecentric image capturing, the system makes it possible to minimize wavelength and amplitude deviations at different angles during the image acquisition of the subject of interest. An efficient hardware module was also developed in the process, including an additional, highly parallel integrated circuit that makes it possible to perform complex preprocessing directly within the unit. To make that possible, it was also necessary to develop a model-based data processing set, not only to minimize random deviations in measurements caused by physical factors, but also to compensate for fluctuations in measurements within the system. These are caused by the illumination process, optical factors, and the spatially and multispectrally resolving sensor module. This also allows the system to reduce additional image noise and, within system capabilities, use algorithms to correct spatial and spectral undersampling.
Adding value for industry and biomedicine
The work carried out by SQB has also offered benefits of a practical nature. In parallel to conducting the research, two verification and validation systems have been developed for use in industrial and biomedical applications. The industrial application integrates the sensor system under development into a process used to carry out visual inspections on pipes with the aim of detecting water droplets. With the biomedical concept, the focus lay in integrating the technology into a hand-held opto-digital dermatoscope.
The MINIMIZE research and development project was supported through funding from the Federal Ministry of Education and Research (BMBF), also featuring in the Digital Optics announcement as part of an initiative called Photonics Research Germany. The partners in the project were Steinbeis Qualitätssicherung und Bildverarbeitung (SQB, which acted as the project coordinator), Technische Universität Ilmenau (represented by its Group for Quality Assurance and Industrial Image Processing), Tailorlux (Münster), FotoFinder Systems (Bad Birnbach), and Lensation (Karlsruhe).
Steffen Lübbecke (author)
Steinbeis Qualitätssicherung und Bildverarbeitung GmbH (Ilmenau)
Paul-Gerald Dittrich (author)
Technische Universität Ilmenau
Department of Mechanical Engineering
Group for Quality Assurance and Industrial Image Processing (Ilmenau)