| 摘要 |
An intrusion detection apparatus for detecting the presence of an intruder in a forbidden space comprises a sensor, an illumination system, a sound system and a still camera. When the sensor detects the presence of an intruder, it switches on the illumination system and the sound system (e.g. a buzzer or an alarm), and activates the still camera to take a picture of the illuminated intruder. The sound system masks the operation of the camera so that the intruder is unaware that a picture has been taken. |
