Abstract: An approach is provided for a device and a method for light adjusting that adjust illumination output based on the environment statues, which comprises a power supply, at least one detector, and at least one controller. The detector is configured for detecting an object in a detecting region. The controller is coupled to the power supply, the detector and a LED lamp, and is configured to provide adaptive power to the LED lamp based on the detections of the detector, wherein the controller provides a high voltage to the LED lamp when the object is detected by the detector. Therefore, it is able to reduce electricity consumption especially for a place requiring long term illumination.