An ultrasonic cleaner is a cleaning device that uses ultrasound (usually from 15-400 kHz) to clean delicate items. They are often employed for cleaning of jewellery, lenses and other optical parts, coins, watches, dental and surgical instruments, fountain pens, industrial parts and electronic equipment. In everyday use such devices may be found in use in most jewelry workshops, watchmakers establishments, or in cellular phone repair workshops (where it could be used for cleaning a phone that has been exposed to enough moisture to hinder its operation).
Industrial ultrasonic cleaners are used in the automotive, sporting, printing, marine, medical, pharmaceutical, electroplating, disk drive components, engineering and weapons industries. Cleaners are also used to experimentally determine the elastic constants of many anisotropic materials. Traditionally, ultrasonic waves can only be sent through a material at angles normal to the materials surface. However, in water the angle of incidence for a longidunal wave can be set, inducing both longitudinal and transverse waves in the material. Then by measuring the time of flight for both waves, the elastic constants can be determined.
