Patent attributes
A 1D ultrasonic transducer unit for material detection, comprising a housing having securing device for securing to a surface and having at least three discrete ultrasonic transducers designed to decouple sound waves with a consistent operating frequency between 20 kHz and 400 kHz in a gaseous medium, and a control unit designed to control each ultrasonic transducer individually, wherein two ultrasonic transducers, directly adjacent to one another, are spaced apart by a distance, the 1D ultrasonic transducer unit has a sound channel per ultrasonic transducer with an input opening, associated with exactly one respective ultrasonic transducer, and an output opening, the output openings are arranged along a straight line, a distance from the directly adjacent output opening corresponds at most to the full or half the wavelength in the gaseous medium and is smaller than the corresponding distance.