Figure 8

(a) Photograph of the fabricated TPENG which can lighten one LED bulb during the moment of being lit up by mechanical force of finger. (b) Applied force was recorded by force sensor when the finger forces of 2 N, 3 N and 4 N are pressed on TPENG. (c) The output voltage of TPENG under the varied forces of 2 N, 3 N and 4 N.