Rachel Lennon
Postgraduate Researcher
Physics and Astronomy
I joined the Xm2 Metamaterials CDT in September 2018. My project, "Towards Flexible Micro-Endoscopy: Compressive Characterisation and Control of Light Propagation Through Multi-mode Optical Fibres" (working title) is supervised by Prof Dave Phillips and Prof Jacopo Bertolotti.
Prior to starting a PhD, I obtained an MPhys in Physics from the University of Exeter in 2018. My dissertation, ‘Modelling the calcium-dependent temporal gating behaviour of Ryanodine Receptors’, was supervised by Prof Jacopo Bertolotti and Prof Christian Soeller, and involved modelling the release of calcium from stores inside heart muscle cells in order to investigate its effect on muscle contraction i.e. the heartbeat.
Conferences
- Light in Complex Materials, Exeter, April 2019 (poster)
- Light@Bath (incubator workshop, secured £2000 with my group for investigation of drug delivery through skin using Raman techniques and fibre optics), May 2019
- Imaging in Wave Physics, Cargese Scienfitic Institute, September 2019
Responsibilities
- Demonstrator for first year undergraduate physics modules "Mathematics Skills I" and "Mathematics for Physicists II", "Stage 1 Physics Problems", "Stage 2 Physics Problems"
- Exam script mark checker for undergraduate physics exams
- Exam support worker (invigilator/scribe/reader/typist) for Special Provisions undergraduate EMPS exams
- Group leader for first year physics Communication Skills course (2019, 2020)
- Chair of the optical, infra-red and THz photonics and plasmonics research group - website (1) and (2)
- Lead of the CDT calendar for outreach opportunities
- Member of the CDT social media team (Instagram) and culture team
- Postgraduate and neurodiversity rep. in the Physics Inclusivity Working Group
- Pint of Science 2020 organiser (Atoms to Galaxies theme)
- City of Exeter Pint of Science Co-ordinator 2020/21
- Postgraduate rep. for the Physics Health and Safety Committee
- Students' Guild Postgraduate Research Representative for the CDT in Metamaterials
PhD project
Towards Flexible Micro-Endoscopy: Compressive Characterisation and Control of Light Propagation Through Multi-mode Optical Fibres
Supervisors
Multi-mode optical fibres make excellent candidates for future micro-endoscopes: promising high-resolution imaging deep inside the body with minimal disruption to surrounding tissue due to their small (~300um diameter) footprint. However, before this can become a reality there are some significant challenges to overcome, which this project aims to address:
As light propagates through optical fibres, the spatial information is scrambled in a complicated manner, meaning that the wavefront emerging from the near end no longer forms an image of the scene at the far end. This scrambling operation must be characterised and inverted to reconstruct the image, which is a complex and time-consuming process. Current methods to characterize the scrambling through optical fibres require access to both the near and far ends. Unfortunately, the scrambling is dependent upon the precise configuration of the optical fibres – any bending, twisting, or changes in temperature alter how the light is scrambled, thus requiring its re-characterisation before image reconstruction can be achieved. This limits the use of such a system as an endoscope where only the near end of the optical fibre is accessible.
In this project we will aim to solve these challenges using a combination of cutting-edge laser beam shaping technology and new computational techniques based on the field of compressive sensing – reconstructing images from undersampled data. The project will involve laboratory-based experiments using lasers, liquid crystal displays and fast cameras. It will also involve programming these devices to work together, and designing new data analysis algorithms.
