| The history of ultrasound began with SONAR (Sound | | | | 1845 proved the Doppler Effect on sound waves: A |
| Navigation and Ranging) for submarines and has had | | | | sound's pitch would change if its source or recipient |
| many uses with varying degrees of success since | | | | was in motion. This was a very significant change to |
| then. | | | | the future of ultrasound. |
| Ultrasound history, medically speaking, has been | | | | - It was discovered in Paris, France in 1880 by Pierre |
| primarily a diagnostic technology although it has been | | | | Curie and his brother Jacques Curie, that electric |
| tested and used for therapy as well. Doctors and | | | | potential would be produced when mechanical |
| sonographers have been capturing images from within | | | | pressure was exerted on a quartz crystal. |
| the human body since the 1940's and in spite of its | | | | - The opposite of which was mathematically deduced |
| varied history, ultrasound has become one of the most | | | | from thermodynamic principles by physicist Gabriel |
| widely used medical diagnostic tools in modern | | | | Lippman in 1881. The generation and reception of |
| medicine. | | | | 'ultrasound' was now possible. |
| - When was ultrasound testing invented? 1826. | | | | - Underwater sonar detection systems were |
| - Who invented ultrasound? Swiss physicist, | | | | developed for the purpose of underwater navigation |
| Jean-Daniel Colladon. | | | | by submarines in World war I. |
| - How was ultrasound discovered? Colladon used an | | | | - The first working sonar system was designed and |
| underwater bell to determine the speed of sound in the | | | | built in the United States by Canadian Reginald |
| water. | | | | Fessenden in 1914. This system was able to detect an |
| - How did ultrasound progress to what is in 2010? | | | | iceberg underwater from 2 miles away. Powerful |
| - Many studied sound vibrations (waves), transmission, | | | | electronic amplifications were necessary for |
| propagation, and refraction throughout the 1800's. | | | | developments in ultrasonic instruments: |
| - English Lord Rayleigh published in 1877 "the Theory of | | | | - French physicist Paul Langévin and Russian |
| Sound" & first described a sound wave as a | | | | scientist Constantin Chilowsky developed an ultrasonic |
| mathematical equation, forming the basis of future | | | | echo-sounding device called the 'hydrophone', the basis |
| practical work in acoustics. | | | | of the development of naval pulse-echo sonar. |
| - Italian biologist, Lazzaro Spallanzani, in 1794 | | | | - Discoveries and developments parallel to echo sound, |
| demonstrated the ability of bats to navigate accurately | | | | such as electro-magnetic RADAR; |
| in the dark via echo reflections from high frequency | | | | - ENIAC, the first digital computer; |
| inaudible sound or 'ultrasound'. | | | | - and the point-contact transistor. |
| - High frequency sound waves (above the limit of | | | | In the Medical field, the heating and disruptive effects |
| human hearing) were generated by English scientist | | | | of ultrasound were applied to therapy, also as a |
| Francis Galton in 1876, through the Galton whistle, | | | | neuro-surgical tool, before being used in the 1940's for |
| which was his invention. | | | | diagnosis. |
| - Austrian physicist Christian Doppler and Buys Ballot in | | | | |