Fully Printed Piezoelectric Polymer Loudspeakers with Enhanced Acoustic Performance

Abstract

Piezoelectric polymer loudspeakers have advantages like lightweight, flexibility, simple structure, and small volume, which make them favorable for a variety of applications. Herein, such loudspeakers are fabricated by screen printing the bottom and top electrodes (poly(3,4-ethylene-dioxythiophene):poly(styrenesulfonate), PEDOT:PSS) as well as the piezoelectric polymer layer (poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE)), in between on paper substrates. The dielectric properties of the printed loudspeakers are studied with dielectric spectroscopy. Thanks to the self-healing process during poling, the samples are successfully poled to saturation in spite of their large area of up to 300 cm 2 . The dependence of the acoustic output on remanent polarization and the active area of the piezoelectric layer is investigated. A sound pressure level (SPL) of about 91 dB at a distance of 1 m is obtained with array samples of five rectangular units (10 Â 6 cm 2 in area each). In particular, samples with two loudspeaker arrays printed, respectively, on both surfaces of the paper substrates are prepared, and a further increase of 6 dB in SPL is achieved when the two loudspeakers are driven in phase. The results not only deepen the understanding of fully printed piezoelectric polymer loudspeakers but also realize an SPL much higher than that reported in previous studies.

Printed Multilayer Piezoelectric Transducers on Paper for Haptic Feedback and Dual Touch-Sound Sensation

“…The printed piezoelectric transducers were manufactured in a similar way as already described previously [ 24 ]. However, for the multilayer approach of this work, the printing design and the sequence of printing was changed.…”

Paper‐Embedded Roll‐to‐Roll Mass Printed Piezoelectric Transducers

“…In the offline polarization scheme, a bipolar butterfly voltage waveform was applied in order to get rid of the contributions from capacitive charging and conduction process. [23,29,30] In the inline polarization scheme, a sinusoidal voltage waveform was applied in order to save time, and the contributions of I cap and I con were removed through the method described in ref. [30].…”

“…[ 22 ] However, for low frequency applications up to a few kHz, the achieved conductivity value is still high enough to avoid large power losses. [ 23 ] Furthermore, for large‐area electronics often defined as low cost electronics, it is important to find a good balance between required performance of single layers and material consumption of the functional layers which significantly influences the costs per device. Besides the economic balance, the ecologic aspect becomes high priority as well.…”

3‐Dimensional Printing of Hydrogel‐Based Nanocomposites: A Comprehensive Review on the Technology Description, Properties, and Applications

“…[ 156 ] Other hydrogels have been extensively used in tissue engineering. [ 156–176 ] Table 4 shows the biological properties, including cellular assay and cell type of hydrogel‐based scaffolds.…”