Superworking principle is the physical principle of using sound waves. The frequency > > 20000Hz is ultrasonic, and the medical ultrasonic frequency is 1~ 15MHz. The essence of ultrasonic wave is sound wave, that is, mechanical wave, so it has no harm of ionizing radiation. At present, it has not been found that ultrasound examination is harmful to human body.

The biological effect of ultrasound on human body is related to ultrasound power and irradiation time. Low-power ultrasonic irradiation time is limited, and it will not produce obvious biological effects. Although high-intensity ultrasound (>: 5W/cm2) is used to crush stones and destroy tumor tissues, it has strong mechanical power. However, diagnostic ultrasound only uses ultrasound as a signal, and the required power is extremely small.

Therefore, diagnostic ultrasound has been considered to be very safe for many years. Under the condition of international safety valve, no obvious side effects were found, including adverse effects on embryos and early pregnant fetuses.

Although ultrasound examination is a very safe imaging examination method, we should be cautious in daily ultrasound diagnosis. That is, to reduce the examination time with the minimum output power, avoid long-term irradiation on fixed parts (especially eyes and early embryos), and minimize some possible side effects caused by ultrasonic irradiation.