Ralf Widenhorn, PhD


Adjunct Associate Professor


Radiation Medicine


Radiation Medicine


Undergraduate Institution: University of Konstanz, Germany; Vordiplom (Pre-diploma) 1997 Graduate Institution: Portland State University, OR; Ph.D 2005 Physics

Expertise and Research:

Dr. Widenhorn works extensively on characterizing and improving digital imagers. His work has been published and presented in different leading journals and conferences at the Society of Photographic Instrumentation Engineers (SPIE), Institute of Electrical and Electronics Engineers (IEEE), and American Physical Society (APS). He serves as chair of the “Sensors and Camera Systems for Scientific, Industrial, and Digital Photography Applications” at the SPIE Electronic Imaging conference. 

Digital imagers are an increasing important part in the medical field. Dr. Widenhorn uses his research knowledge for teaching in the classroom and is exploring medical applications of image sensors. His educational and research interests include medical applications of physics.

Professional Memberships:

SPIE, Oregon Academy of Sciene: an interdisciplinary approach to the science and application of light Oregon Academy of Science.


  • Ralf Widenhorn, Richard Berry, Armin Rest, and Erik Bodegom, “Sensor apparatus and method for noise reduction”, US patent granted 2011, Patent Number: 7880780

  • Ralf Widenhorn, Alexander Weber-Bargioni, Morley M. Blouke, Albert J. Bae, Erik Bodegom, Charge diffusion in the field-free region of charge-coupled devices, Optical Engineering 49(4), 044401 (2010)

  • R. Widenhorn, J.C. Dunlap, and E. Bodegom. Exposure time dependence of dark current in CCD imagers, IEEE Trans. Electronic Devices, 57 (3), 581-587 (2010)

  • J.C. Dunlap, E.Bodegom, and R. Widenhorn, Correction of dark current in consumer cameras, Journal of Electronic Imaging, 19 (1), 013010 (2010)
  • R. Widenhorn, I. Hartwig, J.C. Dunlap, and E. Bodegom. Influence of illumination on dark current in charge-coupled device imagers, Journal of Electronic Imaging, 18(3), 033015 (2009)

  • Ralf Widenhorn, Michael Fitzgibbons, and Erik Bodegom, The Meyer-Neldel rule for diodes in forward bias, J. Appl. Phys. 96, 7379 (2004)

  • Armin Rest, Lars Mündermann, Ralf Widenhorn, Erik Bodegom, and T. C. McGlinn, Residual images in charge-coupled device detectors, Rev. Sci. Instrum. 73, 2028 (2002)

  • Ralf Widenhorn, Armin Rest, and Erik Bodegom, The Meyer-Neldel rule for a property determined by two transport mechanisms, J. Appl. Phys. 91, 6524 (2002)

  • Ralf Widenhorn, Lars Mündermann, Armin Rest, and Erik Bodegom, Meyer-Neldel rule for dark current in charge-coupled devices, J. Appl. Phys. 89, 8179 (2001)

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