Flicker perception in the periphery

Preface I come from Poland. Several months ago I came to Eindhoven to do my studies. I followed master programme Human-Technology Interaction at the Eindhoven University of Technology. In the last phase of this study I joined Philips Research, the group of Visual Experiences, where I completed my graduation project. This report is a result of this project. I would like to thank all the people who contributed to this work. First, I'd like to thank my awesome supervisors, Dragan Sekulovski from Philips Research and Raymond Cuijpers and Yvonne de Kort from TU/e. Without your great support and inspiring ideas I wouldn't be able to complete this research. Further, special thanks to the entire Visual Experience group for the very warm atmosphere and a patience with looking at this not-that-pleasant flickering light. I'd like to thank Tin de Zeeuw, who was always there and listened to whatever I had to say (and for helping me through the labyrinth of HTC); to Alfredo Grunwald and all the internees who made my stay at Philips such a pleasure. Finally, I'd like to thank my best-in-the-world parents for being the best parents in the world. Summary In recent years LEDs (Light Emitting Diodes) began to play an important role in various lighting applications. LEDs, contrary to conventional analogue lights, can easily generate and change a wide range of chromaticites and brightness levels over time. This dynamic capability is a great advantage, but an issue of control may appear at this point. The light change can namely produce effects, which are unattractive and undesirable to people. Flicker is one example of such effects. It is defined as a repeated and quick light alternation, as opposite to a steady light. To prevent LEDs from flickering in an economical way, visibility thresholds have to be known. Visibility thresholds are defined as the largest amplitudes (the distance in change between two colors) for a particular set of parameters that produce steady and not flickering light changes. Previous studies already defined flicker visibility thresholds in human central vision Sekulovski (2007). However, LED-based lighting application can be extended into the periphery, so that they become even more useful and attractive. Human central vision differs from peripheral vision and therefore a new research was required. The goal of this study was to investigate human flicker sensitivity in peripheral vision under mental load. Mental load was introduced because peripheral light is …