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3.
Software ..............................................13
3.1. Program operation ..................................... 13
3.2. Menu functions .......................................... 14
4.
Suggested experiments .......................... 14
4.1. Wave nature of ultrasound ......................... 14
of the transducer in use ............................. 15
4.3. Speed of longitudinally propagated
sound in test bodies ................................... 15
4.4. Attenuation of sound in test bodies ........... 15
4.5. Attenuation of sound in fluids .................... 16
4.6. Frequency-dependent attenuation ............. 16
4.7. Time-dependent amplifier ......................... 17
4.8
Frequency dependence of resolution ......... 18
4.9. Manually guided B image ........................... 18
4.10. Time-motion mode (M mode) ..................... 18
4.11. Transmission coefficient and speed
of transversely propagated sound .............. 19
A scan - testing of materials ...................... 20
5.
Technical details ..................................20
5.1
U10010 Ultrasonic echoscope controls ....... 20
5.2. U10015 1-MHz ultrasonic transducer ......... 20
5.3. U10017 4-MHz ultrasonic transducer ......... 20
5.4. U10027 Acrylic block with holes ................. 20
5.5
U10020 Equipment set for
longitudinal and transverse waves ............. 20
5.6
U10022 Aluminum block with
protractor scale .......................................... 20
5.7. U10023 Polyoxymethylene (POM) plate
with protractor scale .................................. 20
5.8. U10025 Reflection plate ............................. 20
5.9. U10026 Set of three cylinders ..................... 20
5.10. U10029 Heart valve model ......................... 20
tumor ......................................................... 20
6.
Bibliography ........................................ 20
1. Introduction
Ultrasonic echoscopy (also called sonography) has de-
veloped into one of the key procedures for medical
examination and materials technology. Although there
is a confusingly wide range of ultrasonic devices pro-
duced for various applications, all of them rely on the
same basic principle of emitting a mechanical wave
and recording the reflections in an echogram.
2. Components
2.1. Ultrasonic echoscope controls U10010
The U10010 echoscope is an ultrasonic A-image de-
vice with an output for pure pulse echo operation and
an extra output and converter for operation with two
ultrasonic transducers for transmission measurements.
The device is equipped with a parallel interface for
connection to transfer data to a PC.
To make the principle behind the device clearer, the
individual components, receiver, transmitter and time-
dependent amplifier can be viewed separately. The gain
for the amplification of the received signal can be ad-
justed in 5-dB steps from 0 to 35 dB. The transmitter
power can be adjusted in 10-dB steps from 0 to 30 dB.
For time-dependent amplification, the start point, the
rise time, the threshold and the width can all be con-
tinuously adjusted up to a maximum gain of 35 dB.
Also included is the ASH control software for Microsoft
Windows. This allows you to measure amplitude and
timing differentials. It also supports the simultaneous
display of HF signal and amplitude signal so that, un-
like with conventional A-image equipment, the wave
nature of ultrasound can be demonstrated. An addi-
tional chart simultaneously shows the form of and
change in the time-dependent amplification. Other
software options include: manually guided B-images;
time-motion mode; FFT on a selected signal segment;
zoom function; changeover between time and resolu-
tion depending on the speed of sound, which can also
be adjusted; switching between measuring ranges; data
export and print capability; automatic mode display
(transmission or refection).
2.2.
Ultrasonic transducer
2.2.1. Ultrasonic transducer 1 MHz U10015
For examinations at greater depth or examinations in-
volving high power and low depth resolution, 16-mm
piezo-ceramic disc in cast metal housing, preset for
water propagated sound, one cable with frequency-
coded snap-in plug.
2.2.2. Ultrasonic transducer 4 MHz U10017
For examinations requiring maximum depth resolu-
tion at shallow depth, 16-mm piezo-ceramic disc in
cast metal housing, preset for water propagated sound,
1-m cable with frequency-coded snap-in plug.
2.3.
Accessories
2.3.1. Acrylic block with holes U10027
For determining speed of sound and attenuation of
an ultrasonic signal in acrylic (polyacrylate), for pin-
pointing discontinuities, and investigating imaging er-
rors caused by sound shadows or ground echoes, fre-
quency-dependent resolution capacity and display of
a manual B image. To investigate resolution, both the
1-MHz and the 4-MHz transducers are required. Pol-
ished polyacrylate block with drilled holes of various
diameter for simulating discontinuities at various dis-
tances from the surface of the block.
2.3.2. Equipment set for longitudinal and transverse
waves U10020
For investigating the propagation of longitudinal and
transverse (shear) waves in solid bodies and determin-
ing elastic constants (shear modulus, modulus of elas-
ticity and Poisson number) of these bodies. Also for
determining ultrasonic attenuation in fluids by means
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