1. A camera device, comprising: an image capture module to capture images of a determined field; a face detection module to detect the images captured by the image capture module, to obtain a face to be tested in one of the images, and record coordinates of the face to be tested in the image containing the face; a light detection and ranging (LIDAR) to transmit laser light according the coordinates of the face to be tested in the image, to scan the face to be tested in the determined field, thereby to obtain three-dimensional information of the face to be tested; a storage module for storing three-dimensional information of a determined face of a person; and a microprocessor to compare the three-dimensional information of the face to be tested with the three-dimensional information of the determined face, thereby to output a recognition signal according to a result of the comparison.