Ultrasound has great applications in military medical care and industry. Its application can be divided into power ultrasound and detection ultrasound according to the power. Applications of power ultrasound include welding, drilling, crushing, cleaning, emulsification and so on. Most of them belong to ultrasound equipment and only send unacceptable signals. At present, the exact mechanism of ultrasonic machining is still not completely clear. The military application of detection ultrasound includes radar positioning. Medical ultrasound can penetrate muscle and soft tissue, which makes this technology often used for scanning. Obstetric ultrasound is also commonly used for pregnancy examination. Doctors can use ultrasound imaging to see through the body, but because ultrasound can't penetrate the bones, although ultrasound is less harmful to the human body, it still can't completely replace X-rays. The typical ultrasonic frequency is about 2MHz to 10MHz, and the higher frequency is usually used for the vibration wave of urinary calculi. Ultrasound equipment conducted launch and reception tests.
Ultrasonic can also be used for cleaning purposes, which is the best cleaning method at present. It is generally believed that this makes use of the "cavitation" of ultrasonic waves in liquid. In a deep well, you can buy an ultrasonic cleaning machine for hundreds of dollars. The cleaning principle of ultrasonic cleaning machine is to use ultrasonic waves to vibrate clean water, so that tiny bubbles are generated in the water, thus taking away the grease or dirt on the surface of the object when the bubbles float to the water surface. The ultrasonic frequency generated by the cleaning machine is about 20-40 kHz, which can be used to clean jewelry, lenses or other optical instruments, dental instruments, surgical instruments and industrial parts.
General ultrasound equipment is composed of ultrasonic power supply, transducer, horn and tool head except low-frequency pure mechanical ultrasonic whistle. There are two kinds of transducers: piezoelectric ceramic transducer and magnetic transducer. The theory of transducer and horn can also be considered as a specialized subject.