Patent ID: 8754747

Claim:
An authentication device comprising: a registration data storage unit that stores biometric information of a user as registration data; an authentication unit that performs authentication processing by matching input data, which is biometric information input by the user, and registration data, which is stored in the registration data storage unit; an authentication history storage unit that stores an authentication result authenticated by the authentication unit as history information; a prediction unit that acquires a periodic temporal variation of an authentication rate, which succeeds in authentication, using the history information stored in the authentication history storage unit, and predicts whether or not a future authentication rate is lower than a first threshold value, from an authentication rate after a previous time point by a period included in the temporal variation; and an updating unit that updates registration data stored in the registration data storage unit, based on the input data, when it is predicted by the prediction unit that a future authentication rate will be lower than the first threshold value.