Illuminating Neural Paths: Power-Efficient Time-of-Flight ICs for Non-Invasive Functional Brain Imaging

Functional near-infrared spectroscopy (fNIRS) has gained recognition for its potential in compact, wearable, and free-moving brain functional imaging. With the emergence of advanced frequency-domain paradigms, fNIRS is now capable of achieving high spatial resolution, positioning itself as a “wearable functional MRI.” This tutorial will begin by introducing the fundamental principles and theoretical foundations of fNIRS. It will then provide a comprehensive design methodology for developing high-efficiency circuits and systems tailored for fNIRS applications. Furthermore, we will explore the key evaluation techniques for fNIRS systems and discuss their typical use cases in biomedical imaging. By bridging the fields of circuit design and biomedical imaging, this tutorial aims to offer a deeper understanding of the interdisciplinary challenges and opportunities in fNIRS system development, as well as its broader implications for biomedical imaging circuits and systems.