| 摘要 |
PROBLEM TO BE SOLVED: To provide an intercom device by which, in the case of a call by a suspicious perform, the call can be detected and a calling operation can be restricted.SOLUTION: A master unit MPU 209 of a habitable room master unit 2 sounds ringback tones when a calling operation is performed on an entrance slave unit 1, starts a camera 102 and displays a captured video image on a monitor 202. On the other hand, the camera 102 also sends luminosity information when sending a video signal. The master unit MPU reads the luminosity information from the started camera 102, lights on an illumination part 103 if luminosity is lower than a predetermined value, determines an abnormal call if the luminosity does not become equal to or higher than the predetermined value even after the illumination part 103 is lighted on, and does not sound ringback tones in the habitable room master unit 2 and call confirmation tones in the entrance slave unit 1.SELECTED DRAWING: Figure 1 |
