The phased array of piezoelectric transducer

Mechanical sector scanning is performed by a motor driven by a single or multiple piston transducers around a fixed axis or a scanning system formed by rotation. Usually the transducer is placed in a container filled with liquid, the entire system is close to keep contact with the surface of the human skin, and the sound waves of HIFU piezo ceramic emitted by each transducer are swept across the imaging area as the transducer oscillates, eventually forming a fan-shaped scanned image. This system is capable of producing images with an imaging rate of 30 per second and an imaging area angle of 30 to 50 degrees. The system is further refined to minimize vibration and reduce patient discomfort. The linear phase array scanning system is one of the best in three scanning systems. The phase array scans a heart. The phase array scan is controlled by electronic rather than mechanical control.

With the continuous linear array, the array piezo element pickup are delayed and transmitted simultaneously.In the design of the circuit, the initial phase shifter is still analog, and the accuracy of the analog phase modulation is not high, later to change to a digital delay line for phase modulation. In fact, the current IC technology friends exhibition has been graded to produce generate all digital control signals, that is, it is not only the delay of the signal, but also the phase shift can be controlled, even the waveform of the signal (including the frequency, amplitude, and envelope can be changed arbitrarily. Therefore, its function of piezoelectric transducer quartz is more powerful, not only in continuous way .It works in the wave state and can also work in the pulse wave state. This is especially suitable for ultrasound imaging.

In short, with the development of electronics and modern medical science, in recent years,section scanning and imaging technology of ultrasonic humidifier piezoelectric transducer has achieved rapid development, if the single-probe manual scanning B-section imager as the first generation, then it is the fast mechanical scanning image and line array electronic scanning imager for the second generation (real-time image), with electronics acoustic piezoelectric sensor and short-axis focusing using linear array.it is electronic scanning imaging and phased array electronic fan scanning.The image is a third generation (real-time image, high resolution), ultrasonic section imager with electronic computer system processing.It is the fourth generation (real-time image, high resolution, rich grayscale, frozen image, easy to measure).