Ph.D Thesis


Ph.D StudentRosen Shani
SubjectAdvances Towards Human-Scale Holographic Optical Retinal
Prostheses
DepartmentDepartment of Biomedical Engineering
Supervisors ASSOCIATE PROF. Yoav Shechtman
PROF. Shy Shoham


Abstract

Some of the most common causes of blindness are degenerative diseases of the outer retina that result in photoreceptor loss, while the inner retinal neurons are largely maintained functional. A retinal prosthesis based on artificial optical stimulation of the surviving retinal neurons offers a powerful approach towards vision restoration. To better realize the potential of this approach, we previously introduced a holographic wavefront shaping method suitable for power-efficient patterned stimulation of retinal neurons.

Here, to advance towards human translation of this technology, we address the challenges that arise in interfacing it with the human visual system. First, using a detailed model-based design, we construct an optimized holographic display for cellular-resolution optical retinal prosthesis. Next, we perform psycho-physical experiments on normally sighted individuals to characterize and validate the performance of our display. Our results provide evidence for the ability of subjects aided by the display to perform high-acuity demanding visual tasks. We explore the system in versatile spatial and temporal illumination conditions, including short-pulsed excitation and in the presence of holographic speckle, leading to a quantitative characterization of the effects of various visual factors on perceptual quality.  Finally, we develop a deep-learning approach for high quality hologram generation that enhances real-time computational capabilities, which are essential to the device.

This study can inform the ongoing development of optogenetic vision restoration devices as well as additional ophthalmic and holographic instruments, and also has potential implications in our understanding of visual processing.