Philips Research is a global organization within Royal Philips (NYSE: PHG, AEX: PHIA), a leading health technology company focused on improving people’s health and enabling better outcomes across the health continuum from healthy living and prevention, to diagnosis, treatment and home care. Philips leverages advanced technology and deep clinical and consumer insights to deliver integrated solutions. The company is a leader in diagnostic imaging, image-guided therapy, patient monitoring and health informatics, as well as in consumer health and home care. Philips’ wholly owned subsidiary Philips Lighting is the global leader in lighting products, systems and services. Headquartered in the Netherlands, Philips posted 2015 sales of EUR 24.2 billion and employs approximately 104,000 employees with sales and services in more than 100 countries. News about Philips can be found at


The Digital Imaging department in Hamburg is part of Philips GmbH Innovative Technologies and concentrates mainly on medical imaging, medical image processing and analysis. The department has a long history in being at the forefront of medical imaging modalities, by the invention, the adaptation and integration of novel technologies and advanced applications in diagnostic imaging, interventions and therapy. The Digital Imaging department is currently actively engaged in all major imaging modalities together with areas like phase-contrast imaging, radiation therapy, radiation dose optimization, organ modelling, image analytics, radiomics and many more. Philips research has more than 10 years of experience in photon-counting CT and was spearheading some of the early reconstruction and imaging methodologies along many others targeted K-edge imaging for a variety of different contrast elements. Core competencies of the Digital Imaging department fitting the needs of the current project are the processing and reconstruction (FBP and iterative) of spectral, photon-counting data, including 2D and 3D material decompositions, K-edge imaging, mono-chromatic imaging, virtual-non-contrast and iodine maps.

Dr. Ewald ROESSL, Ph.D. (M), Senior Scientist
Ewald Roessl graduated in theoretical physics in 1999 from the University of Technology, Graz, Austria. He received his PhD in cosmology and elementary particle physics from the École Polytechnique Fédérale de Lausanne (EPFL), Switzerland in 2004. In 2005, Dr. Roessl joined Philips Research in Hamburg, where he is currently active in various fields of diagnostic imaging including direct-conversion, spectral imaging for computed tomography (CT), mammography and phase contrast imaging. His work on K-edge imaging was instrumental in the development of a prototype spectral CT system for pre-clinical use. From 2008 on, Dr. Roessl leads research within Philips on differential phase-contrast imaging to investigate the potential for clinical applications. From 2014 on, he leads in addition Philips research on the calibration, pre-processing and reconstruction for photon-counting, spectral CT. Ewald Roessl is author or co-author of more than 28 peer-reviewed publications and numerous US patents and patent applications.

Roland PROKSA, (M), Research Fellow
Roland Proksa is with Philips Research since 1980. He has worked in different research areas, mainly concentrated on system architectures and software/hardware for digital signal processing. He is a world expert in mathematics and real-time hardware implementation of reconstruction methods for medical imaging, including ultrasound, magnetic resonance and X-ray computer tomography. His work has had a large impact on Philips Medical Systems, e.g. for fast magnetic-resonance imaging. Roland Proksa has been most active in Computed Tomography during the last 15 years and has contributed significantly to spectral CT development. He is author of more than 50 journal articles and countless patents.