| 摘要 |
PURPOSE:To detect unauthorized invasion of a part of a human body into a vehicle positively by detecting an induced voltage based on an electromagnetic wave outputted through a hollow oscillator which varies according the opening of a door or the like. CONSTITUTION:A door is closed and an electromagnetic wave is generated at the resonance frequency determined by the shape and dimensions of a hollow resonator from a loop antenna 40 coupled to an oscillator 20 in a car room functioning as a hollow resonator as it is surrounded by metal through a transformer section 21, a coaxial cable 30 and the like. The electromagnetic wave is received with a receiving loop antenna to detect an induced voltage based on the electromagnetic wave. When the door opens or a part of a human body invades into the room, the hollow condition varies to change the energy of the electromagnetic wave being generated. Therefore, variation in the detected induced voltage enables positive detection of unauthorized invasion of a part of a human body. |
