Patent ID: 11930714
Assignee: FUJIFILM CORPORATION
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A piezoelectric film comprising:
a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material; and
electrode layers which are provided on both surfaces of the polymer-based piezoelectric composite material,
wherein in a case where a cross section of the piezoelectric film in a thickness direction is observed with a scanning electron microscope, the polymer-based piezoelectric composite material is divided into two equal regions in the thickness direction, and void volumes of the two regions are measured, a ratio of the void volume obtained by dividing the void volume of the region with a larger void volume by the void volume of the region with a smaller void volume is 1.2 or greater.