Development of a Wireless Ultrasonic Vibration Charging System for Near-Infrared Fluorescence Capsule Endoscopy

Early detection of small bowel tumors remains a major clinical challenge because conventional endoscopy cannot fully visualize the small intestine, and conventional white-light capsule endoscopy (WLICE) cannot reveal submucosal lesions. In addition, the performance of near-infrared (NIR) capsules is constrained by battery life. To address these limitations, this study proposes an NIR capsule endoscopy system powered by ultrasonic wireless charging. The proposed system employs a wireless ultrasonic charging module based on a piezoelectric transducer array to deliver efficient energy transfer for indocyanine green (ICG) near-infrared fluorescence (NIRF) imaging within the capsule. A convolutional neural network (CNN) is integrated to process sensor data in real time for lesion detection, and a dedicated user interface is developed for system operation. The ultrasonic-charged NIRF capsule system not only enhances diagnostic capability but, more importantly, establishes an external charging approach that enables long-term, stable operation of capsule endoscopy, thereby opening a new pathway for gastrointestinal detection.