Professor Marty Banks and Dr. Stephen Cholewiak

UC Berkeley

February 28, 2018 4:30 pm to 5:30 pm

Location: Packard 101

Talk Title: ChromaBlur: Rendering Chromatic Eye Aberration Improves Accommodation and Realism

Talk Abstract: Computer-graphics engineers and vision scientists want to generate images that reproduce realistic depth-dependent blur. Current rendering algorithms take into account scene geometry, aperture size, and focal distance, and they produce photorealistic imagery as with a high-quality camera. But to create immersive experiences, rendering algorithms should aim instead for perceptual realism. In so doing, they should take into account the significant optical aberrations of the human eye. We developed a method that, by incorporating some of those aberrations, yields displayed images that produce retinal images much closer to the ones that occur in natural viewing. In particular, we create displayed images taking the eye’s chromatic aberration into account. This produces different chromatic effects in the retinal image for objects farther or nearer than current focus. We call the method ChromaBlur. We conducted two experiments that illustrate the benefits of ChromaBlur. One showed that accommodation (eye focusing) is driven quite effectively when ChromaBlur is used and that accommodation is not driven at all when conventional methods are used. The second showed that perceived depth and realism are greater with imagery created by ChromaBlur than in imagery created conventionally. ChromaBlur can be coupled with focus-adjustable lenses and gaze tracking to reproduce the natural relationship between accommodation and blur in HMDs and other immersive devices. It can thereby minimize the adverse effects of vergence-accommodation conflicts.

Speaker's Biography: Martin S. Banks is a professor in the UC Berkeley School of Optometry. Before arriving at UCB in 1985, he was a professor of Psychology at the University of Texas at Austin. He received his graduate degree in Development Psychology from the University of Minnesota in 1976. Banks has received many awards for his work on basic and applied research on human visual development, on visual space perception, and on the development and evaluation of visual displays. These include the Boyd R. McCandless Award from the American Psychological Association (1984), Kurt Koffka Medal from Giessen University (2007), Charles F. Prentice Award from the American Academy of Optometry (2016), and Otto Schade Prize from the Society for Information Display (2017). He is a Fellow of the Center for Advanced Study of the Behavioral Sciences (1988), Fellow of the American Association for the Advancement of Science (2008), Fellow of the American Psychological Society (2009), Holgate Fellow of Durham University (2011), WICN Fellow of University of Wales (2011), Honorary Professor of University of Wales (2017), and Borish Scholar of Indiana University (2017). This year he will receive the Edgar D. Tillyard Award from the Optical Society of America.

Steven A. Cholewiak received his bachelor's degree from the University of Virginia in 2006, double majoring in Psychology and Physics. While at UVA, he worked as a research assistant in the laboratories of Gerald Clore, Timothy Salthouse, and Dennis Proffitt. After graduation, he joined the Haptic Interface Research Laboratory with Hong Z. Tan at Purdue University for a year. Steven entered Rutgers University's Perceptual Science program in the Psychology department in 2007 and received his M.S. in 2010 in Cognitive Psychology and Ph.D. in 2012 with advisor Manish Singh. His first postdoc was in the Experimental Psychology department at Justus-Liebig-University Giessen in Germany from 2012 to 2015 with Roland W. Fleming and was co-advised by Steven W. Zucker at Yale University. He is currently a postdoctoral scholar in the UC Berkeley School of Optometry's Vision Science Program and is working with Martin S. Banks.