Retinal Projector

Context:

Visual prostheses are artificial devices used to revert blindness: a medical condition affecting more than 39 million people worldwide (World Health Organization). Over the years, several devices and solutions were proposed, but so far retinal prostheses showed the best performances on patients affected by outer retinal layer dystrophies such as retinitis pigmentosa and age-related macular degeneration.

Unfortunately, retinal prostheses approved by regulatory agencies provided at best a visual angle of 20 degrees and, even if this is already an incredible achievement in medical technology, it does not allow for safe and independent ambulation in open space with obstacles and moving objects. Studies under simulated prosthetic vision identified a visual angle of 30 degrees as the minimal requirement to efficiently complete everyday mobility and manipulation tasks.

In order to further address the quantitative limitations aforementioned, the group of Professor Ghezzi designed and characterised a wide-field curved organic photovoltaic epiretinal prosthesis (POLYRETINA) with a very high pixel density. This high-density implant was conceived to offer a relevant resolution for the patient’s needs through the epiretinal network-mediated stimulation. POLYRETINA is a wide-field high-density epiretinal prosthesis which contains 10,498 photovoltaic pixels (80-µm diameter, 120-µm pitch) distributed with a density of 79.1 pixels mm-2 over a visual angle of 43 degrees.

In preparation for a clinical trial with POLYRETINA, we are looking a very talented and motivated student to design a see-through augmented reality system able to project images in a visual angle of 45 degrees based on a projection system working at 850 nm.

POLYRETINA Retinal prosthesis (Courtesy of Prof. Ghezzi)

 

The master project consists of designing a DMD projector based on a Texas Instruments DMD kit to incorporate an infrared light source at 850 nm and an optical system to generate an image on the retina with a Field of View of at least 40 degrees and with sufficient power light intensity to power the retinal prosthesis.

Project type: Master project.

Contact:

[email protected]