Engineering Photovoltaic Retinal Prostheses

Article: Retinal Prostheses Poised to Provide Artificial Vision to the Blind
Source: Genetic Engineering & Biotechnology News
Article: Retinal Implants Give Artificial Vision to Blind People
Source: École Polytechnique Fédérale de Lausanne (Switzerland), via Technology Networks
Published: March 8, 2021 / March 15, 2021

While efforts at retinal regeneration and retinal transplant are ongoing, another line of research looks into artificial vision using retinal prostheses. Engineers in Switzerland have created a prototype of one such retinal prosthesis and their preliminary tests in a virtual reality program are encouraging. The research team used two parameters to evaluate their system: image resolution and field of vision. The POLYRETINA implant contains 10,500 electrodes, each of which produces one dot of light. Patients would need to learn to interpret the signals from the array of electrodes, similar to recognizing constellations in the pattern of stars in the night sky. The researchers investigated number of electrodes and spacing to provide enough image resolution while keeping the electrodes spaced far enough apart to distinguish one dot from another. Their virtual reality program determined that 10,500 was a good amount of electrodes, and that each electrode stimulated a different part of the retina. In their system, adding more electrodes would not improve image resolution. The second parameter they investigated was field of vision. Tests of field-of-vision angles between 5 degrees and 45 degrees found that 35 degrees is the saturation point for stable object perception. This retinal prosthesis is still a long ways from clinical trials, but the project provides a look into the parameters that engineers consider in designing a system for artificial vision.

My rating of this study: ⭐⭐⭐

Further reading: Retinal Prosthesis Aids Multisensory Perception