Belun Sleep System BLS-100

The Belun Ring (BLS-100) represents a significant evolution in home sleep apnea testing (HSAT), moving away from bulky sensors toward a minimalist ring form factor. As the first FDA-cleared AI-powered wearable of its kind, it captures high-resolution photoplethysmography (PPG) at 200 Hz, alongside 3-axis accelerometry and pulse oximetry. This dense data stream allows its proprietary deep-learning algorithms to not only identify respiratory events but also categorize sleep stages (Wake, NREM, REM) with high accuracy. Clinical evaluations demonstrate a strong correlation with gold-standard polysomnography (PSG) for both AHI (r = 0.89) and total sleep time (r = 0.94). One of its most compelling clinical advantages is the support for multi-night testing, which averages out night-to-night variability and reduces the 'first-night effect' often seen in clinical labs.