| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a proximity sensor capable of reducing the possibility of erroneously detecting an object to be detected. <P>SOLUTION: The proximity sensor comprises: an LC resonance section 1 formed of a detection coil L and a capacitor C to be used for detecting an object to be detected; an oscillation circuit section 2 for oscillating the LC resonance section 1; an oscillation amplitude detection section 3 for detecting an oscillation amplitude of the LC resonance section 1; a signal processing section 4 for determining the presence or absence of the object to be detected in an object detection mode of detecting the object to be detected, and determining the presence or absence of external radio waves in a radio wave detection mode of detecting the external radio waves radiated from the outside, on the basis of detection signals outputted by the oscillation amplitude detection section 3; a signal output section 5 for outputting determination signals on the basis of a determination result of the signal processing section 4; a mode switching section 7 for switching the object detection mode and the radio wave detection mode at undefined timing; and a negative conductance control section 6 for changing negative conductance of the oscillation circuit section 2 according to mode signals outputted by the mode switching section 7. <P>COPYRIGHT: (C)2013,JPO&INPIT |
