摘要 |
An airborne ultrasonic sensor is obtained in which a sensor body and a housing have an integrated structure, and which can reduce spurious waves which propagate through the housing to arrive at the sensor body. The sensor is provided with the sensor body that radiates ultrasonic waves into air and at the same time receives reflected waves from a reflection source which exists in the air, a transmission and reception device that drives the sensor body and at the same time obtains a distance to the reflection source or a propagation speed of sound based on the reflected waves, and the housing that has the sensor body fixedly secured thereto with an integrated structure. The housing has groove portions which are different in acoustic impedance from their surroundings. The groove portions are arranged obliquely regarding either one of a horizontal direction or a vertical direction of the sensor body. |