COPENHAGEN, Denmark — Dr. Johannes Meyer has received the EMVA Young Professional Award 2019 for his work “Light Field Methods for the Visual Inspection of Transparent Objects.” Meyer has been working as a Research Scientist in close cooperation between the Vision and Fusion Laboratory of the KIT and the Visual Inspection Systems department of the Fraunhofer-Institute of Optronics, System Technologies and Image Exploitation IOSB in Germany. In 2018, he obtained a PhD in computer science from the KIT. Since 2019, he has been working for ITK Engineering GmbH in the field of computer vision.
Objects made from transparent materials play crucial roles in humans’ everyday life. They are employed, for example, as windshields, glasses or as plastic lenses to guide laser beams in eye surgery. Especially when considering the latter example, it is obvious that such objects must meet high quality requirements. Hence, a visual inspection for material defects, like enclosed air bubbles or surface scratches, is inevitable. Human visual inspection is a fatiguing task, which is not very robust and prone to subjective results or even to unrevealed defects. Automated visual inspection systems represent a reliable alternative to manual inspection. However, the automated inspection of complex-shaped transparent objects like lenses and windshields still represents a challenging task with several open research questions.
A transparent object itself and the material defects influence the direction of propagation of the transmitted light. Hence, the complete light field, i.e., the position and direction of propagation of the light rays, must be considered for the detection of defects. Accordingly, the thesis of the paper introduces methods based on the concept of light fields for all main components of a visual inspection system, the illumination source, the sensor device, and the signal processing algorithms. A novel sensor system, the laser deflection scanner, allows users to acquire high-resolution light fields of transparent objects. By means of suitable processing algorithms, material defects can be extracted out of these light fields in real time. Furthermore, a method for inverse light field illumination has been developed that suppresses all intended structures of the test objects and reveals material defects with high contrast. A thorough experimental evaluation stated the superiority of the introduced methods over the state of the art with respect to several criteria.
The EMVA Young Professional Award is an annual award to honor the outstanding and innovative work of a student or a young professional in the field of machine vision or image processing. It is the goal of the European Machine Vision Association EMVA to further support innovation in the machine vision industry, to contribute to dedicated machine vision education and to provide a bridge between research and industry. With the annual Young Professional Award, the EMVA intends to encourage students to focus on challenges in the field of machine vision and to apply latest research results and findings in computer vision to the practical needs of the industry. The award winner was announced on May 18 during the 17th EMVA Business Conference in Copenhagen, Denmark, where he also had the opportunity to present his work as part of the regular conference program.
The 18th EMVA Business Conference will take place June 25-27, 2020, in Sofia, Bulgaria.