Ultrasonic transducer, ultrasonic sensor, object detection apparatus, object detection method, and object detection program

An ultrasonic transducer comprising:

• a transducer case that is formed into a bottomed, cylindrical shape that has a side plate portion that is formed into a cylindrical shape that surrounds a center axis and a bottom plate portion that seals one end side of the side plate portion in an axial direction that is parallel to the center axis so as to configure a diaphragm that is capable of ultrasonic vibration;
• and
• an ultrasonic element that is fixedly supported to the bottom plate portion so as to face an interior space that is surrounded by the side plate portion and the bottom plate portion, and converts between an electrical signal and ultrasonic vibrations, wherein
• the ultrasonic element is arranged in a position that is offset in an in-plane direction that is orthogonal to the axial direction relative to a center position of the diaphragm in the in-plane direction so as to be capable of generating a first transmission wave that has first directivity characteristics, and a second transmission wave that has second directivity characteristics that are directivity characteristics that differ from the first directivity characteristics and in which sound pressure in the axial direction is decreased.