Langevin Transducers for In Vitro Diagnostics
Piezoelectric Power Ultrasonic Transducers Enable Fast Sample Preparation
Power ultrasonic transducers, such as the Langevin transducer, consist of multiple components, with piezoceramic rings forming their core. The assembled system generates and amplifies >> ultrasonic waves and then transmits them into the target medium. The resulting pressure changes in the liquid medium cause cavitation, where bubble formation and collapse create local pressure and temperature pulses as well as microjets.
In medical technology, this energy can be used in point‑of‑care devices for applications such as cell lysis, homogenous mixing of liquids, and particle dispersion.
The individual components of the transducer can be specifically tailored to achieve the technical specifications required for other medical applications, such as dental tatar removal, and for industrial uses like ultrasonic cleaning. You can find more information on specific application developments >> here.
Specifications
With over 30 years of expertise in the development and manufacturing of piezoceramics, PI Ceramic offers a comprehensive range of services — from material selection to standard component delivery.
This demonstrator is a fully functional prototype. We will provide you with a customized quote for Langevin transducers upon request.
The dimensions and specifications of the transducers, as well as the electronics, can be individually modified within defined limits. Feasibility is evaluated based on the provided requirements or dimensions.
| Dimensions [mm] | 86 x 19.5 (L x Dm at the node) |
| Resonant frequency f [kHz] | 35 |
| Resonant impedance I [Ω] | <50 |
| Maximum displacement (peak-to-peak) App [µm] | 36 |
| Maximum power consumption P [W] | 5 |
| Quality factor Qm | >2000 |
| Piezoceramics | Hard PZT >> piezoceramic rings are used to generate high-power ultrasound. |
| Electronics | We provide a printed circuit board specifically developed for the Langevin transducer upon request. You can find detailed information in the corresponding >> technical note. |
| Added capabilities | In addition to the configuration shown, custom designs can be created, for example:
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| Applications | This Langevin transducer was specifically designed for medical devices used in the field of in vitro diagnostics. Examples of possible applications can be found >> here. |
Comparative Material Data
In addition to piezoelectric rings made from lead zirconate titanate (PZT), PI Ceramic offers power ultrasonic transducers manufactured with lead-free ceramics.
Rings made from potassium sodium niobate (KNN) cannot replace PZT rings in any application. However, the adapted transducers with lead-free ceramic components achieve specifications that are well suited for point-of-care applications.
Comparative results of lead-free and lead-containing Langevin transducers for use in cell lysis and sample mixing:
The >> material parameters are decisive in achieving the desired specifications of a power ultrasound transducer. The use of lead-free KNN rings reduces the displacement at the same power level and the same voltage. This can be compensated for with a higher drive voltage.
It should be noted that the higher loss factor with lead-free materials at the same displacement amplitude at the tip of the transducer leads to greater heat generation in the rings. In addition, greater self-heating occurs due to a higher power dissipation.
- Cell lysis
- Mixing liquids
- Particle dispersion
Downloads
Material Data
Lead-Free Piezoceramic Materials
Article: Lead-Free Ceramics in Prestressed Ultrasonic Transducers
Technical Note E837T0001
Driver Board for Ultrasonic Transducers