The idea of creating a device capable of identifying sounds and transforming them into images came from the ancient Greeks, who observed animals with ultrasonic characteristics, that is, animals capable of emitting this type of sound (such as bats, for example) , started the study on the subject.
Based on this observation principle, a device capable of identifying objects floating under water, the depth of the sea, among others, was developed during the Second World War. This device is known as sonar.
Ultrasound, even when used at a very high frequency, does not disturb humans, because it does not propagate well in the air and its frequency is soon absorbed by the molecules of the gases that form it.
However, when used at low intensity, it can transmit information and also improve the biological structure of the individual.
An example of the use of low-intensity ultrasound is in medicine, physiotherapy and aesthetics.
Already used at high frequency, it is used in solid and liquid bodies.
Biological and mechanical effects of ultrasound:
• More intense on the tissue surface, which increases the temperature of the place where it is applied;
• Displacement of intercellular particles;
• Muscle relaxation;
• Improves circulation and vascularization;
• Among other benefits and also side effects.
It is the transformation of sound into image. This transformation happens because there is a crystal that forms the ultrasonic waves, called a transducer. This, in turn, is responsible for transforming the mechanical energy of the waves into electrical energy and vice versa. This phenomenon, discovered by Pierre and Jacques Curie in 1880, is known as piezoelectricity.
Electrical energy is found from the vibration of a crystal present in the ultrasound device. This vibration happens due to the movement performed in the device and identified by the crystal. The transducer then indicates the vibration frequency that it is possible to identify because it has a natural resonance frequency that will convert the mechanical vibration of the wave into electricity, which after being interpreted electronically is visible on the monitor.