Thermal control study of miniaturized implantable optoelectronic devices for neural stimulation

Optical neuromodulation is a technique for regulating neural activity using light. Due to the limited penetration depth of light in biological tissues, precise stimulation typically requires implantable optoelectronic devices. Among these, LED-based devices are the most widely used, and their thermal management is critical for ensuring long-term operational stability. This review first discusses the impact of temperature elevation on neural tissue and defines the thermal safety threshold. It then analyzes the primary heat sources within LED chips, encapsulation structures, and circuit modules. The tissue photothermal effect and current thermal monitoring techniques are also introduced. This review provides a comprehensive overview of recent advances in thermal management strategies in light and power modules, wireless communication systems, control algorithms, and encapsulation materials. Moreover, this review underscores key challenges associated with device miniaturization, dynamic stimulation conditions, and encapsulation complexity, while also exploring future directions in the integration of thermal management with emerging intelligent technologies.