SAD Light

A SAD Light, also known as a phototherapy box, is a medical-grade device designed to emit bright, full-spectrum light (typically 10,000 lux) that mimics natural sunlight while filtering out 99% of harmful UV radiation. Modern devices often prioritize specific blue-light wavelengths (460–480 nm) which are most effective at entraining the circadian clock. It is a first-line clinical treatment for Seasonal Affective Disorder (SAD), non-seasonal depression, and circadian rhythm sleep-wake disorders.