My primary research field is that of adaptive optics, a mechatronic system used to overcome the time-varying deleterious effect of the earth’s atmosphere on astronomical imaging. This system consists of a sensor, which measures the instantaneous wavefront distortion due to the atmosphere, an adaptive mirror that can be locally deformed by independent actuators, and a control law to calculate the optimal actuator commands from the wavefront sensor measurements and atmospheric and noise statistics. By correcting for the atmosphere with a deformable mirror, we can compensate for the blurring effect of the atmosphere. In particular, my research is intended to solve problems for the design of the next generation of telescopes, especially the European Extremely Large Telescope (EELT) currently being designed by the European Southern Observatory (ESO).
My secondary research field is in phase-contrast X-ray imaging (i.e. using the phase of the X-ray wavefront rather than the magnitude or absorption as is done for a conventional X-ray image). In particular, I am interested in the area of ptychography, which uses multiple overlapping X-ray diffraction images to reconstruct the sample through iterative phase retrieval algorithms. This research involves reconstructing ptychographic tomographic datasets measured at the European Synchrotron Radiation Facility (ESRF) and numerical simulations of reconstruction algorithms and optimization of physical parameters.
- Engler B., Le Louarn M., Verinaud C., Weddell S. and Clare R. (2019) Pyramid wavefront sensing in the presence of thick spiders. Quebec City, Canada: Adaptive Optics for Extremely Large Telescopes 6, 9-14 Jun 2019. In http://ao4elt6.copl.ulaval.ca/proceedings.html.
- Engler B., Weddell S. and Clare R. (2019) A Digital Prism Wavefront Sensor for Ground-based Astronomical Image Correction. Auckland, New Zealand: International Conference on Image and Vision Computing New Zealand (IVCNZ), 19-21 Nov 2018. In Proceedings - IVCNZ 2018 http://dx.doi.org/10.1109/IVCNZ.2018.8634797.
- Engler B., Weddell S. and Clare R. (2019) A Digital Prism-based Wavefront Sensor Testbench. Quebec City: Adaptive Optics for Extremely Large Telescopes 6, 9-14 Jun 2019. In http://ao4elt6.copl.ulaval.ca/proceedings.html.
- Weddell S., Clare R. and Lambert A. (2019) Near Earth Object Image Restoration with Multi-Object Adaptive Optics. Darmstadt, Germany: Proceedings of the 1st NEO and Debris Detection Conference, 22-24 Jan 2019. In European Space Agency, (Special Publication) ESA SP.
- Engler B., Weddell S., Le Louarn M. and Clare R. (2018) Effects of the telescope spider on extreme adaptive optics systems with pyramid wavefront sensors. Austin, TX, USA: SPIE Astronomical Telescopes + Instrumentation, 10-15 Jun 2018. In Proceedings of SPIE 10703 http://dx.doi.org/10.1117/12.2310050.