A pair of glasses is disclosed. The glasses include a lens made of electrochromic glass; a camera for capturing a foreground image; an infrared sensor circuit for emitting an infrared light, receiving the infrared light reflected by a target object in the foreground image, and determining an emitting time for emitting the infrared light and a receiving time for receiving the reflected infrared light; and a processing circuit for obtaining information of an area of the target object based on the foreground image, the emitting time, and the receiving time, and controlling a change of a voltage applied to the corresponding area based on the information of the corresponding area; a battery for supplying the voltage applied to the corresponding area at the lens to change the voltage applied; and a frame for accommodating the lens, the camera, the infrared sensor circuit, the processing circuit, and the battery.