TMS
Didactic Muse
Page 9
Basic Physic Principles of Imaging Ultrasound
By Rogelio Leyva Ochoa, MSTSM
Learning Objectives: Imaging Ultrasound Physics
In this article you will learn:
Basic principles of the physics technique of ultrasound imaging
No complicated mathematics equations and example lessons
TRANSMISSION AND RECEPTION OF WAVES
When a stone falls into the water (fig.1), it generates waves that go
away in all directions. Now imagine a piece of cork falling into a crystal
container full of water and the observation site is not from above
but from one side (fig. 2). Also imagine, to get rid of all the directions
but one that depart from the cork to the right side, the cork does not go to
the bottom, it enters into the water and goes up to the surface and enters
less deep into the water and goes up again. This happens three,
four… times until it stays steady.
The up and down movements of the cork produces the waves
seen in (fig. 2). In (fig. 3), the waves depart from the cork, and reach the
wall of the container. Figure 4 shows the waves colliding with the wall
and returning to the cork colliding with it. The cork moves up and
down again, so the movements of the falling cork generated waves,
A stone falls into the wa- and the same waves after reaching the end of the container, return
ter, it generates waves in and produce movements in the cork. These movements are smaller
than the ones that generated the waves.
all directions.
Piece of cork falling into
a crystal container full of
water.