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arXiv · 2407.04720

Laser driven miniature diamond implant for wireless retinal prostheses

Arman Ahnood·Ross Cheriton·Anne Bruneau·James A. Belcourt·Jean Pierre Ndabakuranye·William Lemaire·Rob Hilkes·Réjean Fontaine·John P. D. Cook·Karin Hinzer·Steven Prawer
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Abstract

The design and benchtop operation of a wireless miniature epiretinal stimulator implant is reported. The implant is optically powered and controlled using safe illumination at near-infrared wavelengths. An application-specific integrated circuit (ASIC) hosting a digital control unit is used to control the implant's electrodes. The ASIC is powered using an advanced photovoltaic (PV) cell and programmed using a single photodiode. Diamond packaging technology is utilized to achieve high-density integration of the implant optoelectronic circuitry, as well as individual connections between a stimulator chip and 256 electrodes, within a 4.6 mm x 3.7 mm x 0.9 mm implant package. An ultrahigh efficiency PV cell with a monochromatic power conversion efficiency of 55% is used to power the implant. On-board photodetection circuity with a bandwidth of 3.7 MHz is used for forward data telemetry of stimulation parameters. In comparison to implants which utilize inductively coupled coils, laser power delivery enables a high degree of miniaturization and lower surgical complexity. The device presented combines the benefits of implant miniaturization and a flexible stimulation strategy provided by a dedicated stimulator chip. This development provides a route to fully wireless miniaturized minimally invasive implants with sophisticated functionalities.

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Arman Ahnood, Ross Cheriton, Anne Bruneau, James A. Belcourt, Jean Pierre Ndabakuranye, William Lemaire, Rob Hilkes, Réjean Fontaine, John P. D. Cook, Karin Hinzer, Steven Prawer. 2024-06-21. Laser driven miniature diamond implant for wireless retinal prostheses. https://doi.org/10.1002/adbi.202000055

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