Modern lighting design is evolving beyond visibility and energy saving. With people spending over 90% of their time indoors, human-centric and health-measurable lighting has become the new industry frontier. Artificial sunlight lighting scientifically optimizes indoor light spectrum to match natural daylight features, supporting human physiology, improving comfort, productivity and long-term indoor health. It abandons exaggerated marketing concepts and focuses on transparent, measurable and responsible indoor lighting performance.