| 摘要 |
PROBLEM TO BE SOLVED: To effectively prevent, through simple authentication work, illegal use due to a third person other than a regular user. SOLUTION: When using a digital camera 1, the user carries a signal transmitter 16 together with the digital camera 1 and presses a transmission start button 17a of the signal transmitter 16. If a power button 7a is pressed, the digital camera 1 monitors the status of reception of a signal reception unit 12. When the signal reception unit 12 receives a signal from the signal transmitter 16 within a predetermined time, an ID for authentication included in that signal is collated with a user ID in a user ID storage unit 14a and when the both are matched, acceptance of an operation signal is allowed, so that the digital camera 1 is turned into available state. If the signal reception unit 12 does not receive any signal even after the lapse of the predetermined time, on the other hand, the acceptance of the operation signal is prohibited, and an alert message is displayed on an LCD 9. COPYRIGHT: (C)2006,JPO&NCIPI |
