Going up to infrared or optical frequencies, classical antenna technology fails due to the lack of efficient localized feeds. At such frequencies, emitters generally rely on distributed feeds. Each point of the extended source zone emits fields randomly, so that the total fields generated by the device are only partially spatially coherent. The partially spatially coherent aspect of the fields has received limited attention so far, especially in the engineering community. However, it is well known that the spatial coherence of the fields plays a key role in shaping and enhancing the radiation from thermal and electroluminescent sources. In this project, we propose a framework where the fields emitted by such sources are decomposed into an incoherent sum of fully coherent modes. During this project, we will develop a versatile open-source software that can simulate such devices using a full-wave integral equation method. This software can be used to study thermal or electroluminescent emitters of various geometries while rigorously accounting for the partial coherence of the fields. The software will be validated through experiments and shared with the community. Using the modal framework, an extended reciprocity theorem between the fields emitted by thermal or electroluminescent sources and the fields they absorb that includes the partially coherent aspect will be derived and validated through experiments. This project is expected to deeply impact the field since no such tool that can rigorously account for the partial coherence of the fields has been proposed so far. Moreover, the experimental characterization of emitters will be easier using the extended reciprocity. This project will be done in the University of Cambridge in collaboration with J.-J. Greffet (France) and C. Craeye (Belgium). Through this project, the researcher will develop skills in experimental research, which he is currently missing to reach an independent position.

One of the grand challenges of computer graphics has been to generate images indistinguishable from photographs for a naïve observer. As this challenge is mostly completed and computer generated imagery starts to replace photographs (product catalogues, special effects in cinema), the next grand challenge is to produce imagery that is indistinguishable from the real-world. Tremendous progress in capture, manipulation and display technologies opens the potential to achieve this new challenge (at the research stage) in the next 5-10 years. Electronic displays offer sufficient resolution, frame rate, dynamic range, colour gamut and, in some configurations, can produce binocular and focal depth cues. However, most of the work done in this area ignores or does not sufficiently address one of the key aspects of this problem - the performance and limitations of the human visual system. The objective of this project is to characterise and model the performance and limitations of the human visual system when observing complex dynamic 3D scenes. The scene will span a high dynamic range (HDR) of luminance and provide binocular and focal depth cues. In technical terms, the project aims to create a visual model and difference metric for high dynamic range light fields (HDR-LFs). The visual metric will replace tedious subjective testing and provide the first automated method that can optimize encoding and processing of HDR-LF data. Perceptually realistic video will impose enormous storage and processing requirements compared to traditional video. The bandwidth of such rich visual content will be the main bottleneck for new imaging and display technologies. Therefore, the final objective of this project is to use the new visual metric to derive an efficient and approximately perceptually uniform encoding of HDR-LFs. Such encoding will radically reduce storage and bandwidth requirements and will pave the way for future highly realistic image and video content.