With Protractor Scale; L55/1 Model Of A Single Breast With Benign Tumor; Software; Program Operation - 3B SCIENTIFIC PHYSICS U10010 Manuel De L'utilisateur

of time-dependent amplitude measurement with
moveable reflector.
Ultrasound is first passed vertically through a body
under test placed in a trough filled with water. Only
longitudinal waves are propagated through the body.
The transmission amplitude of these is recorded. In
rotating the body to ever greater angles, the ampli-
tude of the longitudinal waves decreases and trans-
verse waves are increasingly propagated through the
body. These appear in the amplitude domain as a sec-
ond peak.
From the angle where total reflection of the longitudi-
nal waves takes place, the speed of the longitudinal
waves can be calculated. The speed of transverse waves
can be calculated from the angle where the maximum
transmission amplitude for transverse waves occurs. If
the body is rotated further, total reflection of the trans-
verse component may also occur depending on the
magnitude of the speed of sound in proportion to that
in the surrounding fluid.
From the two speeds of sound, the elastic constants
(shear modulus, modulus of elasticity and Poisson
number) for the body under test can be calculated.
Acrylic (included in the scope of delivery), aluminum
and polyoxymethylene (POM) plates are available as
test bodies. The speed of transverse waves in acrylic
(polyacrylate) is almost exactly the same as in water.
In aluminum the speed is greater and in POM it is
smaller than in water.
Set consists of sounding trough, acrylic test plate in
holder with protractor scale and two transducer hold-
ers for 1-MHz or 4-MHz ultrasonic transducers that al-
low for precise positioning of the transducers on the
sounding trough.
2.3.3. Aluminum plate with protractor scale U10022
Accessory for longitudinal and transverse waves equip-
ment set for investigating the propagation of transverse
waves in metals and for determining the elastic con-
stants such as shear modulus, modulus of elasticity and
Poisson number for aluminum; high quality reflector
(large reflection coefficient in water) and therefore easy-
to-measure signal amplitudes for attenuation meas-
urements in liquids (e.g. water, cooking oil, glycerine).
2.3.4. Polyoxymethylene (POM) plate in test holder
with protractor scale U10023
Accessory for longitudinal and transverse waves equip-
ment set for investigating the propagation of transverse
waves in plastic and for determining the elastic con-
stants such as shear modulus, modulus of elasticity and
Poisson number for POM.
2.3.5. Reflection plate U10025
Polished acrylic plate for investigating multiple ech-
oes and measuring frequency-dependent attenuation.
The 4-MHz transducer is particularly suited for meas-
urements of this kind. Initially an echo image with at
least three echoes is recorded and the spectrum of the
individual echoes analyzed. The result is a shifting of
the median frequency to lower frequencies since the
higher frequency components are more strongly at-
tenuated.
2.3.6. Set of 3 cylinders U10026
Polished polyacrylate cylinders for determining speed
of sound and attenuation of ultrasound in acrylic.
Measurements can be made using reflection mode or
transmission mode.
2.3.7. Heart valve model U10029
Twin chamber with rubber membrane and pressure
regulator for demonstrating the action of heart valves
using the time-motion method. During the experiment,
the membrane chamber produces an image similar to
that produced by a valve of a beating heart in an elec-
trocardiogram as used for medical diagnosis.
2.3.8. Model of a single breast with benign tumor
Imitation breast made of silicon with a simulated be-
nign tumor for demonstrating B-image mode.

3.1. Program operation

As soon as the program is started, the measuring equip-
ment is immediately activated. The user interface is
shown in the illustration above. In the top part of the
screen, the A-image signal, the current position of the
markers (vertical red and green lines), the frequency
of the receiving transducer that is connected and the
current mode (reflection/pulse echo or transmission).
The markers can be positioned using the mouse (the
mouse cursor changes when the markers are to be
moved).
The scale for the time axis (time measurement) can be
switched to display distance (depth measurement)
["Time"/"Depth" buttons]. An entry for the speed of
propagation as required for calculation can be made
using the Settings option in the menu (default: 1000
m/s). The UP-DOWN button pairing at the left-hand edge
of the screen is for changing the amplitude resolution
(top) and shifting the zero-axis (bottom).
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3.Software