Table 1.
Comparison with state-of-the-art thin-film loudspeakers
| Design | Material | Active area (cm2) | Distance (cm) | Voltage (Vrms) | SPL @ 1 kHz (dB SPL) | Sensitivity (mPa/V cm2) | Bandwidth (kHz) |
|---|---|---|---|---|---|---|---|
| This work | PVDF | 9 × 9 | 30 | 7.07 | 61 | 0.039 | >100 |
| Ref. 17 | PVDF | 21 × 30 | 100 | 20 | 70 | 0.017 | 7 |
| Ref. 19 | P(VDF-TrFE) | 10 × 6 | 5 | 35.4 | 63 | 0.0022 | 13 |
| Ref. 20 | P(VDF-TrFE) | 10 × 6 | 100 | 17.7 | 55 | 0.035 | 8 |
| Ref. 22 | PZT/GNP | 20 × 17 | 30 | 135 | 72 | 0.0017 | >20 |
| Ref. 23 | COC | 12 × 12 | 100 | 70.7 | 55 | 0.0037 | >20 |
| Ref. 24 | COP | 15 × 15 | 50 | 56.5 | 18 | 0.000021 | >20 |
| Ref. 25 | EAP | π × (10/2)2 | 100 | 283 | 75 | 0.017 | 1 |
For sensitivity comparison, the reported SPLs at 1 kHz are converted into acoustic pressure under a 1 Vrms drive voltage for loudspeakers of unit area (1 cm2) at 30 cm away. The normalization is conducted assuming a far-field response of linear loudspeakers, i.e., acoustic pressure proportional to (active area × voltage)/distance. The bandwidths are estimated from the roll-off trend of the reported frequency responses of these devices.
PVDF polyvinylidene fluoride, [P(VDF-TrFE)] poly(vinylidene fluoride-co-trifluoroethylene), COC cyclic-olefin copolymers, COP cyclic-olefin polymers, PZT lead zirconate titanate, GNP graphene nanoplatelets, EAP elastomer electroactive polymer.