Match previously registered face image for face recognition with the face image to check and save the number of matchings. By comparing the most matching face recognition image with the authentication image, the speed of face recognition can be significantly improved even when the number of face image increase due to increased number of users. In addition, this invention replaces the less matching count image with a new face image, and can naturally reflect the face change due to growth or aging

After photographing the user, the invention selects random location of user’s face image to move the photographing unit until the face can be moved into the optimal face authentication area to change the direction taken. The invention can maximize the convenience of the face recognition without the movement of the user

in order to solve the gradually lowered accuracy of face recognition during face recognition process due to deteriorating infrared lighting on users’ face that with time, one or more user face images are stored to each reference illuminance level when users register. This mechanism enables high recognition rate of the users’ face even when the infrared illuminating lamp deteriorates.

internal workers register in advance through the face recognition for access control. Visitors are to call workers inside through calls or face recognition system. By logging the face of the visitor to the office, a more reliable access control is possible.