journal article·2025-04-03Open access

Wireless Digital Controller for High-Density Stimulation Devices: Enhancing Resolution and Minimizing Crosstalk

Yeonji Oh, Jonggi Hong, Jungsuk Kim

Applied Sciences· Volume 15· Issue 7

Abstract

Recent advances in micro-retinal implant technologies have shown promise in vision restoration, yet challenges remain regarding pixel resolution, reliability, power leakage, cost-effectiveness, and device lifespan. Existing devices often face difficulties meeting the long-term safety and reliability requirements set by regulatory bodies such as the FDA and the European Union, making them impractical for widespread use. This research introduces a 256-pixel hexagonal subretinal device with an advanced digital controller designed to overcome these limitations. The proposed system offers solutions to issues of resolution, compactness, economic constraints, and control over biphasic pulse parameters. It was specifically designed to deliver flicker-free vision while increasing resolution and light sensitivity. A prototype was developed using field-programmable gate arrays (FPGAs) and amplitude-shift keying (ASK) modulators for wireless data transmission. The system was fabricated on a microchip and tested against various performance parameters, demonstrating its potential for future commercial viability.
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Research context

OpenAlex topics: Neuroscience and Neural Engineering · Conducting polymers and applications · Advanced Memory and Neural Computing

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Medical Science, Korea University, Seoul 02841, Republic of Korea

Department of Health Sciences & Technology, Gachon Advanced Institute for Health Sciences & Technology, Gachon University, Incheon 21999, Republic of Korea

Department of Biomedical Engineering, Gachon University, Seongnam 13120, Republic of Korea

Funding

National Research Foundation of Korea

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