Ultrasonic Transducers - Envirocoustics

Transducer Selection
The transducer is one of the most critical components of any
ultrasonic system. A great deal of attention should be paid to
selecting the proper transducer for the application.
The performance of the system as a whole is of great importance.
Variations in instrument characteristics and settings as well as
material properties and coupling conditions play a major role in
system performance.
We have developed three different series of transducers to
respond to the need for variety. Each series has its own unique
characteristics.
mV / Division
0.8
0.4
0.0
-0.4
-0.8
0.8
0.4
0.0
-0.4
-0.8
0.8
0.4
0.0
-0.4
-0.8
SIGNAL WAVEFORM
( 0.2 µsec / Division )
SIGNAL WAVEFORM
(0.2 µsec / Division)
SIGNAL WAVEFORM
(0.2 µsec / Division)
2 www.olympusNDT.com
(VOLT)
(VOLT)
ACCUSCAN “S”
The Accuscan S series is intended to
provide excellent sensitivity in those
situations where axial resolution is
not of primary importance. Typically
this series will have a longer wave
form duration and a relatively narrow
frequency bandwidth.
CENTRASCAN
The piezocomposite element
Centrascan Series transducers
provide excellent sensitivity with a
high signal-to-noise ratio in
difficult-to-penetrate materials. They
have exceptional acoustic matching
to plastics and other low impedance
materials.
VIDEOSCAN
Videoscan transducers are untuned
transducers that provide heavily
damped broadband performance.
They are the best choice in
applications where good axial or
distance resolution is necessary or in
tests that require improved
signal-to-noise in attenuating or
scattering materials.
Transducer configuration also has an impact on system
performance. Consideration should be given to the use of focused
transducers, transducers with wear surfaces that are appropriate for
the test material, and the choice of the appropriate frequency and
element diameter.
The summaries below provide a general description of the
performance characteristics of each transducer series. While
these guidelines are quite useful, each application is unique and
performance will be dependent on electronics, cabling, and
transducer configuration, frequency, and element diameter.
Note: For more information on bandwidth and sensitivity versus resolution,
please refer to the Technical Notes located on pages 39-48.
Note: For sample test forms of transducers that you are interested in purchasing
or if you have questions, please contact us via phone, fax, or e-mail.
1.0
0.8
0.6
0.4
0.2
1.0
0.8
0.6
0.4
0.2
2.25
FREQUENCY SPECTRUM
3.85
-6 dB
0.0
0 5
(MHz)
10
0
-10
dB -20
-30
-40
2.67
FREQUENCY SPECTRUM
-6 dB
0.0
0 5
(MHz)
10
6.2
FREQUENCY SPECTRUM
-50
0 5
(MHz)
10
7.0
7.8