Method and device for unlocking mobile terminal

1. A method for unlocking a mobile terminal, comprising:

when a mobile terminal is in a locking state, determining a time length for an object to stay close to a screen of the mobile terminal and to be maintained within a pre-determined distance range;

generating a corresponding unlocking signal according to the time length; and

unlocking the mobile terminal according to the unlocking signal;

wherein generating the corresponding unlocking signal according to the time length comprises:

comparing the time length with a pre-set time length; and

when the time length is greater than the pre-set time length, generating an unlocking signal, which is used for indicating that the time length is greater than the pre-set time length, and when the time length is smaller than or equal to the pre-set time length, generating an unlocking signal, which is used for indicating that the time length is smaller than or equal to the pre-set time length;

wherein unlocking the mobile terminal according to the unlocking signal comprises:

combining the unlocking signal with one or more previously-generated unlocking signals to form an unlocking signal sequence;

comparing the unlocking signal sequence with a pre-set signal sequence; and

when the unlocking signal sequence is matched with the pre-set signal sequence, unlocking the mobile terminal, and when the unlocking signal sequence is not matched with the pre-set signal sequence, maintaining in the locking state.

2. The method as claimed in claim 1 , wherein before determining the time length for the object to stay close to the screen of the mobile terminal and to be maintained within the pre-determined distance range, the method further comprises: starting, by the mobile terminal, a distance sensor, which is used for detecting a distance between the object and the screen of the mobile terminal.

3. The method as claimed in claim 2 , wherein determining the time length for the object to stay close to the screen of the mobile terminal and to be maintained within the pre-determined distance range comprises:

detecting, by the mobile terminal, the distance between the object and the screen of the mobile terminal in real time by using the distance sensor, and determining whether the distance is maintained within the pre-determined distance range; and

measuring a time during which the distance is maintained within the pre-determined distance range to obtain the time length.

4. The method as claimed in claim 1 , wherein the unlocking signal sequence is generated by repeatedly covering a distance sensor of the terminal with different time lengths.

5. The method as claimed in claim 1 , the method further comprises:

displaying a signal type corresponding to each generated unlocking signal on the screen of the mobile terminal.

6. A mobile terminal unlocking device, comprising:

a time determination element, configured to determine, when a mobile terminal is in a locking state, a time length for an object to stay close to a screen of the mobile terminal and to be maintained within a pre-determined distance range;

a signal generation element, configured to generate a corresponding unlocking signal according to the time length; and

an unlocking element, configured to unlock the mobile terminal according to the unlocking signal;

wherein the signal generation element comprises:

a signal comparison sub-element, configured to compare the time length with a pre-set time length; and

a signal generation sub-element, configured to generate, when the time length is greater than the pre-set time length, an unlocking signal, which is used for indicating that the time length is greater than the pre-set time length, and generate, when the time length is smaller than or equal to the pre-set time length, an unlocking signal, which is used for indicating that the time length is smaller than or equal to the pre-set time length;

wherein the unlocking element comprises:

a signal combination sub-element, configured to combine the unlocking signal with one or more previously-generated unlocking signals to form an unlocking signal sequence;

a sequence comparison sub-element, configured to compare the unlocking signal sequence with a pre-set signal sequence; and

an unlocking sub-element, configured to unlock, when the unlocking signal sequence is matched with the pre-set signal sequence, the mobile terminal, and maintain, when the unlocking signal sequence is not matched with the pre-set signal sequence, in the locking state.

7. The device as claimed in claim 6 , wherein the time determination element comprises:

a distance sensor, configured to start, before determining the time length for the object to stay close to the screen of the mobile terminal and to be maintained within the pre-determined distance range, and is used for detecting a distance between the object and the screen of the mobile terminal in real time.

8. The device as claimed in claim 7 , wherein the time determination element further comprises:

a timing sub-element, configured to measure a time during which the distance is maintained between the object and the screen of the mobile terminal within the pre-determined distance range to obtain the time length.

9. The device as claimed in claim 6 , wherein the unlocking signal sequence is generated by repeatedly covering a distance sensor of the terminal with different time lengths.

10. The device as claimed in claim 6 , the device is further configured to display a signal type corresponding to each generated unlocking signal on the screen of the mobile terminal.