Ultrasonic sensor having transmission device and reception device of ultrasonic wave

1. An ultrasonic sensor for detecting an object, comprising:

a substrate;

a transmission device for transmitting an ultrasonic wave;

a plurality of reception devices for receiving the ultrasonic wave; and

a circuit for processing received ultrasonic waves, which are received by the reception devices after the ultrasonic wave transmitted from the transmission device is reflected by the object, wherein

the transmission device and the reception devices are integrated into the substrate,

the number of the reception devices is equal to or larger than three so that the circuit is capable of detecting an operation failure,

each of the transmission device and the three reception devices has a surface for transmitting or receiving the ultrasonic wave, the surface being perpendicular to a ground,

the three reception devices are composed of a first to a third reception devices,

the first reception device is disposed above the third reception device, and disposed on a left side of the second reception device,

the circuit is capable of calculating a horizontal plane distance between the object and the sensor in a horizontal plane parallel to the ground and a horizontal plane direction angle from the sensor to the object in the horizontal plane on the basis of the received ultrasonic waves received by the first and the second reception devices,

the circuit is further capable of calculating a vertical plane distance between the object and the sensor in a vertical plane perpendicular to the ground and a vertical plane direction angle from the sensor to the object in the vertical plane on the basis of the received ultrasonic waves received by the first and the third reception devices, and

the circuit is capable of checking the horizontal and the vertical plane distances and the horizontal and the vertical plane direction angles on the basis of the received ultrasonic waves received by the second and the third reception devices so that the circuit is capable of detecting the operation failure.

2. An ultrasonic sensor for detecting an object, comprising:

a substrate;

a transmission device for transmitting an ultrasonic wave;

a plurality of reception devices for receiving the ultrasonic wave; and

a circuit for processing received ultrasonic waves, which are received by the reception devices after the ultrasonic wave transmitted from the transmission device is reflected by the object, wherein

the transmission device and the reception devices are integrated into the substrate,

the number of the reception devices is equal to or larger than four,

each of the transmission device and the four reception devices has a surface for transmitting or receiving the ultrasonic wave, the surface being perpendicular to a ground,

the four reception devices are composed of a first to a fourth reception devices,

the first reception device is disposed above the third reception device, and disposed on a left side of the second reception device,

the fourth reception device is disposed under the second reception device, and disposed on a right side of the third reception device,

the circuit is capable of calculating a horizontal plane distance between the object and the sensor in a horizontal plane parallel to the ground and a horizontal plane direction angle from the sensor to the object in the horizontal plane on the basis of the received ultrasonic waves received by the first and the second reception devices, and further capable of calculating a vertical plane distance between the object and the sensor in a vertical plane perpendicular to the ground and a vertical plane direction angle from the sensor to the object in the vertical plane on the basis of the received ultrasonic waves received by the first and the third reception devices, so that a first data of the object is obtained,

the circuit is capable of calculating the horizontal plane distance and the horizontal plane direction angle on the basis of the received ultrasonic waves received by the third and the fourth reception devices, and further capable of calculating the vertical plane distance and the vertical plane direction angle on the basis of the received ultrasonic waves receive by the second and the fourth reception devices, so that a second data of the object is obtained, and

the circuit is capable of checking the first data and the second data so that the circuit is capable of detecting the operation failure.

3. An ultrasonic sensor for detecting an object, comprising:

a substrate;

a transmission device for transmitting an ultrasonic wave;

a plurality of reception devices for receiving the ultrasonic wave; and

a circuit for processing received ultrasonic waves, which are received by the reception devices after the ultrasonic wave transmitted from the transmission device is reflected by the object, wherein

the transmission device and the reception devices are integrated into the substrate, and wherein

each of the transmission device and the reception devices is provided by an ultrasonic element,

the ultrasonic element is disposed on a membrane of the substrate,

the ultrasonic element includes a piezoelectric thin film and a pair of metallic electrodes so that a piezoelectric vibrator is provided,

the piezoelectric thin film is sandwiched by the metallic electrodes,

the piezoelectric vibrator is capable of resonating together with the membrane at a predetermined ultrasonic frequency,

the transmission device has a planar area of the membrane, and

each reception device has a planar area of the membrane, which is smaller than that of the transmission device.