1, multiple reflection: ultrasonic vertical irradiation to the flat interface and the formation of sound waves reflected back and forth between the probe and the interface, there are multiple echoes of equal distance, intensity gradually weakened, especially on the interface formed by thin layer of gas, such as between the left lobe of the liver and the gas in the stomach, the small echo before the bladder echo.

2. Multiple internal reverberation: the ultrasound is reflected back and forth in the target, forming comet tail sign, such as intrauterine contraceptive ring.

3. Section thickness artifact, also known as partial volume effect, is caused by the wide width of the acoustic beam (that is, the thick section thickness of the ultrasound section). This is an image of pseudobiliary mud in the gallbladder.

4. Sidelobe artifact: caused by sidelobe reflection outside the main lobe of the acoustic beam, presenting "dog ears" or "yarn" -like images on both sides of strong echoes such as stones and intestinal gas.

5. Acoustic shadow: due to the presence of strong reflection or acoustic attenuation in the front, the longitudinal anechoic area which cannot be reached by the acoustic beam is called acoustic shadow area. The acoustic shadow can be used to identify stones, calcification foci and bones, etc.

6, refraction sound shadow: ultrasound from the low speed of sound medium into the high speed of sound medium, in the Angle of incidence exceeds the critical Angle, the total reflection, so that the rear sound shadow, in the spherical structure on both sides of the rear or both sides of the organ edge, also known as the edge sound shadow.

7, mirror artifact: ultrasound beam projection to the surface of the smooth human body strong echo large interface such as the diaphragm surface, like light projection to the plane mirror, produce similar real, virtual two images, such as the diaphragm on both sides of the symmetric two mass echo.

Advantages of ultrasonic imaging: high precision because the ultrasonic energy can penetrate the subtle gaps and small holes, so it can be applied to any parts or assembly parts cleaning. When the cleaned parts are precision parts or assembly parts, ultrasonic cleaning often becomes the only way to meet its special technical requirements;

Compared with conventional cleaning methods, rapid ultrasonic cleaning is much faster in dust removal and scale removal of workpiece. Assembly can be cleaned without disassembly. Ultrasonic cleaning can save labor advantages often make it become the most economic cleaning method; No matter whether the cleaned parts are large or small, simple or complex, single or batch or on automatic assembly line, ultrasonic cleaning can be used to obtain the unrivaled and uniform cleanliness of manual cleaning.