Transducer Technology
The dolphicam2 ultrasound camera has a transducer with 128 transmitting electrodes x 128 receiving electrodes creating a 2D array of 16.384 elements over the 32×32 mm transducer (16 elements/mm2), capable of detecting very small defects. dolphitech provides transducers with different frequency and coupling material (delay line). View the chapter about Transducer Modules to see what we can offer.
The transmitting electrodes crosses the receiving electrodes in a 90° angle. In between the transmitting and receiving electrodes, there is a piezoelectric material that generates the ultrasound.
To collect a pulse-echo-signal from a transducer element, an 70V pulse is excited on the transmitting electrode creating a sound field along the entire transmitting electrode, hence across all the receiver electrodes. The ultrasound goes through coupling and/or material and the reflected pulse is sampled on only one receiver electrode. Hence, the sampled pulse only represents one transducer element, which is the cross between the transmitting and receiving electrode.
Transducer Naming convention
Each transducer module is marked with a type description. The first three letters (TRM) is just short for Transducer Module to describe what dolphicam2 part it is. The model name (BD) is a two-letter combination that describes the transducer model in the TRM. The different transducer models vary in center frequency, bandwidth and coupling pad material & thickness. The last number in type description is the center frequency of the transducer.
Transducer Modules
dolphitech currently offers 5 main transducer frequencies. These can be combined with any coupling pad or coupling shoe/wedge/water box. The figures below show the frequency spectrum for these main transducer frequencies measured with Rexolite coupling and an adapted transmitting pulse.
The table below shows the different transducer modules we offer. The current transducers are all 2D array transducers with 128×128 (16384) transducer elements with element pitch 250 µm x 250 µm. There is one specific transducer module name for each coupling thickness is given. Note that if you choose another thickness on your coupling pad, the module name will be different.
Transducer Frequency Spectrum Overview
Transducer Module Table
Transducer Module Name | Center Frequency | Bandwidth (6dB) | Coupling |
TRM-BA-2.25MHz | 2.25 MHz | 1.50 MHz | Rexolite (8mm*) |
TRM-BF-2.25MHz | 2.25 MHz** | 1.50 MHz** | Aqualene 320 (8mm*) |
TRM-BG_2.25MHz | 2.25 MHz** | 1.50 MHz** | Aqualink 100 (8mm*) |
TRM-AA-3.50MHz | 3.50 MHz | 2.50 MHz | Rexolite (8mm*) |
TRM-AF-3.50MHz | 3.50 MHz | 2.50 MHz | Aqualene 320 (8mm*) |
TRM-AG-3.50MHz** | 3.50 MHz** | 2.50 MHz** | Aqualink 100 (8mm*) |
TRM-CC-6.00MHz** | 6.00 MHz** | 6.00 MHz** | Rexolite (8mm*) |
TRM-DB-8.00MHz | 8.00 MHz | 5.50 MHz | Rexolite (8mm*) |
TRM-DA-11.00MHz** | 11.00 MHz** | 8.00 MHz** | Rexolite (8mm*) |
*Available in thickness: 3mm, 5mm, 8mm, 10mm, 12mm.
** Preliminary Data (Updated numbers coming soon)
Transducer Plots
TRM-BA-2.25MHz
Input Transmit Signal 0-70V, 140ns pulse length
TRM-AA-3.50MHz
Input Transmit Signal 0-70V, 120ns pulse length
TRM-CC-6.00MHz
Input Transmit Signal 0-70V, 70ns pulse length
TRM-DB-8.00MHz
Input Transmit Signal 0-70V, 50ns pulse length
TRM-DA-11.00MHz
Input Transmit Signal 0-70V, 40ns pulse length
Coupling PADS (Delay Lines)
dolphitech offers a range of different coupling materials in different thickness. Typical thicknesses are in the range 3-12 mm.
Coupling Name | Acoustic Velocity | Attenuation @5MHz | Hardness | Material Type | Acoustic Impedance[Mrayl] |
Rexolite | 2304 m/s | 0.33DB/mm | Hard/Solid | Plastic based | 2.5 |
ACE 400* | 1600 m/s | 0.5 dB/mm | Shore A = 40 (**) | Thermoplastic | 1,49 |
Aqualene 300* | 1578 m/s | 0.35 dB/mm | Shore A = 58 (**) | Thermoset | 1.57 |
Aqualene 320* | 1569 m/s | 0.15 dB/mm | Shore A = 35 (**) | Thermoset | 1.55 |
AquaSilox 100* | 1001 m/s | 0.80 dB/mm | Shore A = 23 (**) | Silicon based | 0.91 |
Aqualink 100* | 1484 m/s | 0.4 dB/mm | Shore A = 5 (**) | Thermoplastic | 1.63 |
*Coupling Pad produced by Innovation Polymers based on dolphicam2 transducer design. Check www.innocationpolymers.ca for detailed material properties
(**) Lower Shore A value equals softer material (more elastic).
Coupling Shoes & Wedges
Water box
Can be ordered with different water-delay distance.
FTD – Flexible Transducer Development
dolphitech can also deliver transducers in different sizes, resolution, shapes, frequencies, couplings. We can also modify Transducer Module housing as well as software functionality. Please contact us for requests.