Abstract: The present invention provides a time-of-flight (TOF) device. The TOF device includes an infrared light emitter and an infrared light receiver, the infrared light emitter emits an infrared light along a first direction (X-axis), a right angle prism disposed on a movable base, and the infrared light passes through the right angle prism. A first actuator and a second actuator are respectively disposed beside the movable base. By actuating the first actuator, the right angle prism is tilted toward a second direction (Y axis), and by actuating the second actuator, the right angle prism is tilted toward a third direction (Z axis), and the second direction and the third direction are both perpendicular to the first direction.

Abstract: The present invention provides a method of operating a security monitoring system. A security monitoring system is provided, and it includes at least one 2D monitor and a 3D sensor. First, the 2D monitor is activated, when a person is at a first length from the security monitoring system, the person is continuously tracked by the 2D monitor, and when the person continues to approach the security monitoring system, after the person is at a second length from the security monitoring system, the second length is less than the first length, the 3D sensor is activated to receive a facial information of the person, and compared with an authentication data of a database.

Abstract: A three-dimension (3D) sensor disposed in a static space, the 3D sensor emits a first infrared light when initially turned on, the first infrared light is reflected by the static space, and then received by the 3D sensor and recorded as a first signal. Next, the 3D sensor emits an infrared light in every interval times, and the infrared light will be reflected by static space each time. The reflected feedback signals are recorded and are sequentially compared to the first signal. When the feedback signal is equal to the first signal, the 3D sensor continues to operate, and when a human body enters the static space, causing the feedback signal to be different from the first signal, the 3D sensor identifies the human body to get an identified information, and comparing the identified information with an authentication database saved the 3D sensor.