Patent ID: 7949881

Claim:
A mobile terminal device comprising: biometric information detecting means for detecting biometric information; encryption-key generating means for generating an encryption key on the basis of the biometric information detected by the biometric information detecting means, in personal-identification-number registration; encrypting means for encrypting a predetermined personal identification number with the encryption-key generated by the encryption-key generating means to generate a biometric encrypted personal-identification-number, in the personal-identification-number registration; encrypted personal-identification-number storing means for storing the biometric encrypted personal identification number generated by the encrypting means, in the personal-identification-number registration; decryption key generating means for generating a decryption key on the basis of the biometric information detected by the biometric information detecting means, in personal-identification-number verification; decrypting means for decrypting the biometric encrypted personal-identification-number stored in the encrypted personal-identification-number storing means with the decryption key generated by the decryption-key generating means to reproduce the personal identification number, in the personal-identification-number verification; personal-identification-number verifying means for comparing the personal identification number reproduced by the decrypting means with a personal identification number stored in advance in a personal-identification-number storing means to perform the personal-identification-number verification for enabling a predetermined function; and personal-identification-number determining means for determining, on the basis of biometric information detected by the biometric information detecting means, the reproduction of the personal identification number, in the personal-identification-number verification, wherein the personal-identification-number verifying means has an automatic authentication mode in which the personal identification number decrypted by the decrypting means is used to perform the personal-identification-number verification and a manual authentication mode in which a personal identification number directly input by a user with operating means is used to perform the personal-identification-number verification, and wherein the personal-identification-number verifying means performs the personal-identification-number verification in either the automatic authentication mode or the manual authentication mode, which mode is selected in advance by the user.