Bio-inspired visual systems based on curved image sensors and synaptic devices

Vision is our dominant sense and is also highly desired in artificial systems. In this article, we provide an overview of bio-inspired visual systems that utilize curved image sensors and/or photonic synapses. The use of curved detector geometry ensures clear image sensing abilities with fewer optical elements, which has the potential to lead to miniaturization. Additionally, photonic synapses that integrate light sensing and neuromorphic preprocessing can reduce redundant modules and signal communications. This results in decreased device size and energy consumption. In this review, we begin by summarizing the fabrication processes of curved image sensors, followed by a review of typical bionic eye systems. Next, we discuss the materials and device structures of typical photonic synapses and related imaging systems. We also review the combinations of curved image sensors and photonic synapses. Finally, we summarize the key advantages and challenges of current bio-inspired visual systems.