An ultrasonic transmitter is a transmitter which produces emissions in the ultrasonic range, at a frequency too high for the human ear to detect. Ultrasonic transmitters should not be confused with ultrasonic transceivers, which are capable of transmitting and receiving information in the same unit. In order to receive information, a separate ultrasonic receiver is needed with an ultrasonic transmitter. The two may be sold together if they are intended to be used as a pair, or they can be purchased separately.
There are a wide range of applications for an ultrasonic transmitter, and these devices can be seen in use in many different applications. Hardware and electronic stores often carry these devices, sometimes packaged as part of specialty products. People may also build their own for custom applications, or order these devices through manufacturers.
One situation in which an ultrasonic transmitter might be used is in communications via ultrasound. These can include the transmission of various forms of data. For example, some games require users to use ultrasonic transmitters to control the game, with the movements of the transmitter and the activations of various buttons being sent to a base console via ultrasound. These devices can also be used in other types of communications units as well.
Animals such as dogs and bats are capable of hearing ultrasound. This can be turned to good use with an ultrasonic transmitter which can be heard by animals, but not people. The device may be used to transmit a warning sound or signal which animals are trained to respond to, or which animals will respond to because it resembles alarm calls and other communications made by wild animals.
Ultrasonic transmitters are also used in ultrasonic materials testing, in which sound waves are beamed at a device and a receiver is used to collect information about how the sound interacts with the material. Variations in sound can reveal cracks, air bubbles, and other flaws.
These devices are also used in range finding. A paired transmitter and receiver can be used to collect information about the location of a target with the use of beamed sound waves, which can be used for mapping, aiming weapons, and a variety of other tasks. Similarly, ultrasonic transmitters are used in ultrasonic cleaning devices, with the ultrasound creating cavitation in the cleaning fluid which acts to scour objects placed in the device. One setting in which ultrasonic cleaning can be seen is in jewelsmithing, where rings and other jewelry items are cleaned with ultrasound because it is gentle and highly effective.