Terminal device and computer program

1. A terminal device, comprising:

an authentication information acquirer acquiring multiple different pieces of authentication information;

a separate authentication procedure executer executing a separate authentication procedure based on each piece of authentication information acquired by the authentication information acquirer;

a total authentication determiner determining whether authentication is successful or failed from a combination of results of multiple separate authentication procedures performed by the separate authentication procedure executer; and

unlocking means for unlocking a device to allow operations when the total authentication determiner determines that the authentication is successful, wherein

the separate authentication procedure executer comprises

a first authentication procedure executer executing an authentication procedure by a piece of authentication information acquired by the authentication information acquirer;

an authentication information accumulator accumulating a piece of another authentication information acquired by the authentication information acquirer; and

a second authentication procedure executer executing an authentication procedure based on the piece of other authentication information accumulated in the authentication information accumulator,

the total authentication determiner

determines whether authentication is successful or failed by the authentication executed by the first authentication procedure executer, and further determines, in a background, whether authentication is successful or failed by the authentication executed by the second authentication procedure executer, and

comprises a switching controller evaluating authentication results obtained in the authentication procedure by the second authentication procedure executor and switching from the authentication by the first authentication procedure executor to the authentication by the second authentication procedure executor when the authentication by the second authentication procedure executer is determined to satisfy a predetermined criterion, and

the piece of authentication information is a password, and the piece of other authentication information is a piece of biological information.

2. The terminal device according to claim 1 , wherein

the authentication information acquirer acquires the multiple different pieces of authentication information while a user is using the terminal device, and

the piece of other authentication information further includes location information of the terminal device.

3. The terminal device according to claim 1 , wherein

the authentication information acquirer acquires multiple pieces of other authentication information, and

the second authentication procedure executer executes an authentication procedure based on the multiple pieces of other authentication information acquired by the authentication information acquirer.

4. The terminal device according to claim 1 , wherein,

the switching controller switches from the authentication by the first authentication procedure executor to the authentication by the second authentication procedure executor when a predetermined or more amount of pieces of other authentication information is accumulated in the authentication information accumulator and the total authentication determiner determines that the authentication procedure executed by the second authentication procedure executor is successively successful a reference or higher number of times.

5. The terminal device according to claim 1 , wherein,

for each of the multiple pieces of authentication information acquired by the authentication information acquirer, the separate authentication procedure executor executes a separate authentication procedure based on each piece of authentication information on the basis of a reference level at which the authentication cannot be determined to be successful in authentication by a single piece of authentication information, and

the total authentication determiner determines whether the authentication is successful or failed from a combination of results of multiple separate authentication procedures performed by the separate authentication procedure executer.

6. The terminal device according to claim 1 , wherein the authentication information includes:

information based on which the separate authentication is determined to be successful only when the information completely matches reregistered information; and

information based on which the separate authentication is determined to be successful when a degree of match between the information and reregistered information is equal to or higher than a reference level.

7. The terminal device according to claim 1 , wherein

points scored when the authentication is determined to be successful in the separate authentication procedure is set for each piece of authentication information, and

the total authentication determiner adds up the points scored in the separate authentication procedures and determines that the authentication is successful when the total points are equal to or higher than a reference value.

8. The terminal device according to claim 7 , wherein

for some of the authentication information, a criterion for regarding the authentication unsuccessful regardless of the total points when the criterion is satisfied is set.

9. A computer program for causing a computer to function as the terminal device according to claim 1 .