Optical wavefront shaping for targeted neurophotonic applications
File(s)
Author(s)
Whiteley, Isabell
Type
Thesis
Abstract
Two novel optical imaging systems developed for neurophotonic application are presented, and
an algorithm and computational model for a third novel system is introduced. All systems use
optical elements to shape the wavefront of light to provide different forms of resolution improvement based on different application needs. The first provides high axial resolution optical
sectioning with a large field of view for potential volumetric in vivo imaging of neuronal activity.
The second system provides a precise spatial targeting solution to permit monitoring of fluorescence dynamics with temporal bandwidths on the order of a kilohertz. The system is designed to record single trial, low-signal voltage fluctuations in ex vivo and in vivo imaging experiments.
In the first, a line-scanning temporal focusing system optimised for a wide field of view while
maintaining high axial resolution is systematically characterised. Proof of concept work displaying
high resolution, large lateral field of view volumetric imaging in whole drosophila brain samples is shown.
The second system described is a direct imaging optical system designed for simultaneous highspeed imaging of multiple neurons. It uses a digital micromirror device to switch between regions of interest at a 10kHz refresh rate. The precision of targeting reduces the background noise and provides a signal to noise ratio capable of recording single trial, spontaneous fluorescent voltage changes of less than 10%.
The third system described is a holographic imaging system using a digital micromirror device.
It uses a binary amplitude hologram to project to targeted regions of interest in both two- and
three- dimensions. The system was designed for application in targeted optogenetic activation
of neurons.
Finally, potential optimisations of the two imaging systems are discussed and characterisation
experiments for the new imaging pathway, adapted from the direct imaging system, is proposed.
an algorithm and computational model for a third novel system is introduced. All systems use
optical elements to shape the wavefront of light to provide different forms of resolution improvement based on different application needs. The first provides high axial resolution optical
sectioning with a large field of view for potential volumetric in vivo imaging of neuronal activity.
The second system provides a precise spatial targeting solution to permit monitoring of fluorescence dynamics with temporal bandwidths on the order of a kilohertz. The system is designed to record single trial, low-signal voltage fluctuations in ex vivo and in vivo imaging experiments.
In the first, a line-scanning temporal focusing system optimised for a wide field of view while
maintaining high axial resolution is systematically characterised. Proof of concept work displaying
high resolution, large lateral field of view volumetric imaging in whole drosophila brain samples is shown.
The second system described is a direct imaging optical system designed for simultaneous highspeed imaging of multiple neurons. It uses a digital micromirror device to switch between regions of interest at a 10kHz refresh rate. The precision of targeting reduces the background noise and provides a signal to noise ratio capable of recording single trial, spontaneous fluorescent voltage changes of less than 10%.
The third system described is a holographic imaging system using a digital micromirror device.
It uses a binary amplitude hologram to project to targeted regions of interest in both two- and
three- dimensions. The system was designed for application in targeted optogenetic activation
of neurons.
Finally, potential optimisations of the two imaging systems are discussed and characterisation
experiments for the new imaging pathway, adapted from the direct imaging system, is proposed.
Version
Open Access
Date Issued
2024-01
Date Awarded
2024-09
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Rowlands, Christopher
Schultz, Simon
Sponsor
Engineering and Physical Sciences Research Council
Publisher Department
Bioengineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)