DEVELOPMENT OF 3D DIGITAL HOLOGRAPHY FOR TRACKING MOSQUITO FLIGHT 1=Engineering 2=Sensors and Instrumentation

There are fundamental challenges to quantitative, high dynamic range 3D imaging over large volumes, room sized spaces. This project is motivated by our groups work in quantifying mosquito behaviour in order to design novel and new interventions to mitigate the spread of infectious disease which is a collaboration with Liverpool School of Tropical Medicine (LSTM). To our knowledge, we are the only group currently investigating in vivo spatial activity of mosquitoes at such a comprehensive and detailed level. The collaboration between UoW optical engineers and LSTM vector biologists started in 2011 and has developed unique video tracking systems that have enabled unprecedented characterisation of Anopheles sp. and Culex sp. mosquito host-seeking behaviour at insecticide treated bed nets. Our research approach is distinctive, permitting investigation of vector behaviours not previously possible, and already shown to be a rapid and productive route to new tools. The groups have a joint track record of 7 project awards (5 current). The current activities are largely applied research involving optical imaging and data analytics to derive natural behaviours. This PhD project proposal seeks to investigate a more challenging 3D imaging methodology based on digital holography (DH) to overcome the limitations of existing approaches: accuracy of the 3D positional information obtained, ease of implementation in the field, ability to measure over an extended volume and to image through bednet materials. DH is a relatively new imaging modality in which the complex wavefront scattered from a scene is recorded interferometrically at a digital detector. Computational methods are employed to back propagate the wavefront to planes of interest within the measurement volume enabling reconstructions of both phase and amplitude. The majority of successful DH applications have been at the micron to millimetre scale. This project will explore extending the dynamic range of DH to metre scale volumes within micron scale resolution. The ability to detect the phase of the scattered field is expected to be particularly helpful in imaging mosquitoes which will generate a characteristic phase perturbation which can be used to guide the reconstruction algorithms to identify the plane, and hence 3D position, of individual mosquitoes. The outputs of the research will be reported in high ranking optical engineering journals, such as Optics Express, Optics Letters and Applied Optics. LSTM have confirmed that they are happy to support trials of the instrument in their insectaries to examine, for example, detailed behaviour of mosquitoes approaching faults in bednets and the design of novel mosquito traps. Hence, further publications can be expected in higher ranking journals. Our existing projects will provide a platform for exploitation in the field as appropriate.