Transducer types

Focused transducers | Pulsed transducers | Multi-use transducers

The ultrasonic transducer is the heart of an ultrasonic sensor. It is the link between the sensor electronics and the measuring environment.

At SECO, we specialize in the development and production of ultrasonic transducers for use in air and gaseous media. Our transducers are robust. They also work reliably in dust, fog, reflective surfaces and darkness. Depending on the size, they operate at nominal frequencies in a range from 75 to 500 kHz and achieve ranges from 1 centimeter to 8 meters, depending on the measuring task.

Our transducer assortment is divided into three basic types:

Multi-use transducers

Multi-use transducers are our flexible all-rounders.

Our multi-use transducers consist of a piezo ceramic and a matching disk.

Basic data:

Compact design and small diameter
high echo voltage and long range
fast decay
very large beam width
Sound lobe can be focused (optional)
cost-effective construction

Our tip: The 300 kHz transducers are particularly suitable for anemometry applications.

Our multi-use transducer

Focused transducers

Focused ultrasonic transducers are the perfect choice for long ranges.

We add a metal ring to the piezoceramic and matching disk design.

Basic data:

Well-focused sound lobe
small beam width
maximum sound paths
high quality with high echo voltage
slightly longer decay time
narrowest frequency bandwidth

Our tip: We manufacture focused ultrasonic transducers in robust metal housings as standard.

Our focused transducer

Pulsed transducers

Pulsed transducers are the professionals for fast measurements at close range.

Basic data:

Fastest rise and decay time
Excitation with pulse or a few cycles
Very high repetition rates
short measuring distances

Our tip: Due to its wide frequency bandwidth, the focused transducer can be operated with different excitation principles: at discrete operating frequencies, with sweep or pulse excitation.

Pulsed transducer

The advantages of our transducer assortment

Multi-use transducer:

large opening angle
compact design
cost-effective design

Focused transducer:

long range
minimum opening angle
high echo voltage

Pulsed transducer:

perfect for close range
fast decay
high repetition rates
for compact measuring tasks/instrument dimensions

Key data of the three transducer types

Nominal frequency [kHz]	75…500
Frequency dispersion around nominal frequency [kHz]	± 10…15
Rel. echo voltage (order of magnitude)	1
Burst cycles	12…32
Echo decay cycles (at 1⁄2 UE)	6…10
Öffnungswinkel bei -3 dB [°]	12…20
Opening angle at -3 dB [°]	5000
Min. “blind zone” [mm]	50

Nominal frequency [kHz]	80…500
Frequency dispersion around nominal frequency [kHz]	± 6…20
Rel. echo voltage (order of magnitude)	10
Burst cycles	32…80
Echo decay cycles (at 1⁄2 UE)	10…20
Opening angle at -3 dB [°]	6…8
Max. Range (SECO test circuit) [mm]	8000
Min. “blind zone” [mm]	50

Nominal frequency [kHz]	80…400
Frequency dispersion around nominal frequency [kHz]	± 20 … 40
Rel. echo voltage (order of magnitude)	0,2
Burst cycles	Puls oder 1…12
Echo decay cycles (at 1⁄2 UE)	2…4
Opening angle at -3 dB [°]	9…12
Max. Range (SECO test circuit) [mm]	500
Min. “blind zone” [mm]	20

Further information on our transducer assortment:

For almost thirty years, we have specialized in the development and production of air ultrasonic transducers. Our transducers are characterized by their high flexibility and durability in numerous sensory measurement tasks. Even harsh measuring conditions have no negative effect on the measurement result. For use in particularly demanding environments (salt, cold, heat, chemicals), we can equip your transducer with a water and dirt-repellent coating on the front surface or an additional heater, or adapt the material of our components to the corresponding area of application. Find out more about our design options.

Using ultrasonic waves, our transducers – like bats – determine the presence or distance of a reflective object. They also obtain information about the nature and movement status of a reflector or transport medium. Depending on their size, our transducers operate at nominal frequencies in a range from 75 to 500 kHz and, depending on the measurement task, achieve ranges from 1 centimeter to 8 meters. The electro-acoustic properties of your transducer – as well as the physical structure – can be adapted to the boundary conditions of your measurement task. Find out more about our standard products or browse through our special solutions.

High-quality material as the key to outstanding ultrasonic transducers

The functionality of our ultrasonic transducers depends crucially on the quality of the piezo ceramic, the matching material and the damping matrix. We obtain our piezo ceramics – specially formulated for us – from our main supplier in Germany. We manufacture the fitting material in-house according to proven recipes. For the damping matrix, we use complex potting compound systems that we have optimized over decades of experience. We also assemble our strands in-house. This enables us to adapt all components flexibly, quickly and easily to individual customer requirements. Click here for our know-how.

Our product assortment is divided into three transducer types. Their functionality is based on the same technology, which we have further developed with regard to special application benefits. We differentiate between multi-use transducers, focused and pulsed transducers. Our multi-use transducers are flexible all-rounders whose electro-acoustic properties we have taken to a new level with the enhanced SC5X series. You can find out which transducer type is best suited to your application here.

Customized special solutions – no problem!

We are also happy to create new products for unusual measurement tasks, adapt your transducers to your specific application as part of a customization or further develop our existing products. Get in touch with us! We look forward to the challenge.