Professor Colin Sheppard

Nanophysics Department at the Italian Institute of Technology, Genoa, Italy

March 16, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Confocal microscopy: past, present and future.

Talk Abstract: Confocal microscopy has made a dramatic impact on biomedical imaging, in particular, but also in other areas such as industrial inspection. Confocal microscopy can image in 3D, with good resolution, into living biological cells and tissue. I have had the good fortune to be involved with the development of confocal microscopy over the last 40 years. Other techniques have been introduced that overcome some of its limitations, but still it is the preferred choice in many cases. And new developments in confocal microscopy, such as focal modulation microscopy, and image-scanning microscopy, can improve its performance in terms of penetration depth, resolution and signal level.

Speaker's Biography: Colin Sheppard is Senior Scientist in the Nanophysics Department at the Italian Institute of Technology, Genoa. He is a Visiting Miller Professor at UC-Berkeley. He obtained his PhD degree from University of Cambridge. Previously he has been Professor in the Departments of Bioengineering, Biological Sciences and Diagnostic Radiology at the National University of Singapore, Professor of Physics at the University of Sydney, and University Lecturer in Engineering Science at the University of Oxford. He developed an early confocal microscope, the first with computer control and storage (1983), launched the first commercial confocal microscope (1982), published the first scanning multiphoton microscopy images (1977), proposed two-photon fluorescence and CARS microscopy (1978), and patented scanning microscopy using Bessel beams (1977). In 1988, he proposed scanning microscopy using a detector array with pixel reassignment, now known as image scanning microscopy.


Professor Bas Rokers

University of Wisconsin - Madison

March 23, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Fundamental and individual limitations in the perception of 3D motion: Implications for Virtual Reality

Talk Abstract: Neuroscientists have extensively studied motion and depth perception, and have provided a good understanding of the underlying neural mechanisms. However, since these mechanisms are frequently studied in isolation, their interplay remains poorly understood. In fact, I will introduce a number of puzzling deficits in the perception of 3D motion in this talk. Given the advent of virtual reality (VR) and the need to provide a compelling user experience, it is imperative that we understand the factors that determine the sensitivity and limitations of 3D motion perception.

I will present recent work from our lab which shows that fundamental as well as individual limitations in the processing of retinal information cause specific deficits in the perception of 3D motion. Subsequently, I will discuss the potential of extra-retinal (head motion) information to overcome some of these limitations. Finally, I will discuss how individual variability in the sensitivity to 3D motion predicts the propensity for simulator sickness.

Our research sheds light on the interplay of the neural mechanisms that underlie perception, and accounts for the visual system’s sensitivity to 3D motion. Our results provide specific suggestions to improve VR technology and bring virtual reality into the mainstream.

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Speaker's Biography: Bas Rokers is Associate Professor in the Department of Psychology and a member of the McPherson Eye Research Institute at the University of Wisconsin - Madison. His work in visual perception aims to uncover the neural basis of binocular perception, visual disorders and brain development. In 2015 he was a Visiting Professor in the Department of Brain and Cognitive Sciences at MIT, and he can currently be seen in the National Geographic television series Brain Games on Netflix.


Visiting Assistant Professor Haricharan Lakshman

Stanford University

March 30, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Cinematic Virtual Reality: Creating Immersive Visual Experiences


Dr. Nicolas Pégard

U.C. Berkeley

April 6, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Compressive light-field microscopy for 3D functional imaging of the living brain.

Talk Abstract: We present a new microscopy technique for 3D functional neuroimaging in live brain tissue. The device is a simple light field fluorescence microscope allowing full volume acquisition in a single shot and can be miniaturized into a portable implant. Our computational methods first rely on spatial and temporal sparsity of fluorescence signals to identify and precisely localize neurons. We compute for each neuron a unique pattern, the light-field signature, that accounts for the effects of optical scattering and aberrations. The technique then yields a precise localization of active neurons and enables quantitative measurement of fluorescence with individual neuron spatial resolution and at high speeds, all without ever reconstructing a volume image. Experimental results are shown on live Zebrafish.

More Information:

Speaker's Biography: Nicolas Pégard received his B.S. in Physics from Ecole Polytechnique (France) in 2009, and his Ph.D. in Electrical Engineering at Princeton University under Prof. Fleischer in 2014. He is now a postdoctoral researcher at U.C. Berkeley under the supervision of Prof. H.Adesnik (Molecular and Cell Biology dpt.) and Prof. L.Waller. (Electrical Engineering and Computer Science dpt.) His main research interests are in optical system design and computational microscopy. He is currently developing all-optical methods to observe and control the activity of individual neurons in deep, live brain tissue with high spatial and temporal resolution.


Nicholas Frushour

Canon Mixed Reality

April 13, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Practical uses of mixed reality in a manufacturing workflow


Professor Brian Wandell


April 27, 2016 4:15 pm to 5:15 pm

Location: Packard 101

Talk Title: Learning the image processing pipeline

Talk Abstract: Many creative ideas are being proposed for image sensor designs, and these may be useful in applications ranging from consumer photography to computer vision. To understand and evaluate each new design, we must create a corresponding image-processing pipeline that transforms the sensor data into a form that is appropriate for the application. The need to design and optimize these pipelines is time-consuming and costly. I explain a method that combines machine learning and image systems simulation that automates the pipeline design. The approach is based on a new way of thinking of the image-processing pipeline as a large collection of local linear filters. Finally, I illustrate how the method has been used to design pipelines for consumer photography and mobile imaging.

More Information:

Speaker's Biography: Brian A. Wandell is the first Isaac and Madeline Stein Family Professor. He joined the Stanford Psychology faculty in 1979 and is a member, by courtesy, of Electrical Engineering and Ophthalmology. Wandell is the founding director of Stanford’s Center for Cognitive and Neurobiological Imaging, and a Deputy Director of the Stanford Neuroscience Institute. He is the author of the vision science textbook Foundations of Vision. His research centers on vision science, spanning topics from visual disorders, reading development in children, to digital imaging devices and algorithms for both magnetic resonance imaging and digital imaging. In 1996, together with Prof. J. Goodman, Wandell founded Stanford’s Center for Image Systems Engineering


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