PIR sensors detect human movement, while ultrasonic sensors can detect the presence of stationary users and support sitting-position detection. By combining both sensing technologies, the system can improve detection accuracy and reduce false judgments of user absence caused by prolonged periods of inactivity.

The system can automatically turn the lighting on or off, or adjust the brightness according to different usage scenarios, providing both energy efficiency and user convenience. These technologies are widely used in office spaces, residential environments, reading lights, and smart lighting systems, creating a comfortable and efficient lighting experience.