foil detector

例句：

1. 1. The foil detector was used to detect the presence of explosives in the area.
   箔探测器被用来检测该地区的爆炸物。
2. 2. The foil detector was used to detect the presence of electronic devices in the room.
   箔探测器被用来检测房间里的电子设备。
3. 3. The foil detector was used to detect the presence of metal objects in the area.
   箔探测器被用来检测该地区的金属物体。