Title:
PIEZOELECTRIC ELEMENT, PROBE, ULTRASONIC MEASUREMENT DEVICE, ELECTRONIC APPARATUS, POLARIZATION TREATMENT METHOD AND INITIALIZATION DEVICE
Document Type and Number:
Japanese Patent JP2017034527
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To reduce magnitude of an electric field required to perform polarization treatment in a piezoelectric element having a horizontal electrode structure.SOLUTION: Three electrodes of a first electrode 68, a second electrode 70 and a third electrode 72 are linearly disposed at equal intervals on one side face of a piezoelectric material 66 in a piezoelectric element 62. When ultrasonic waves are received by utilizing a piezoelectric effect, an electric potential difference (voltage) between the first electrode 68 and the third electrode 72 is taken out as a detection signal of the ultrasonic waves. Polarization treatment with respect to the piezoelectric material 66 being initialization for utilizing the piezoelectric effect is performed by sequentially applying an electric field for the polarization treatment in the predetermined same direction among the electrodes adjacent to each other. More specifically, an electric field V1 for the polarization treatment is applied between the first electrode 68 and the second electrode 70 first, and, subsequently, the electric field V1 for the polarization treatment is applied between the second electrode 70 and the third electrode 72. In this case, the electric field V1 for the polarization treatment is half of that when the polarization treatment is performed by applying the electric field between the first electrode 68 and the third electrode 72 at one time.SELECTED DRAWING: Figure 5
Inventors:
MIYAZAWA HIROSHI
YAMADA MASAYOSHI
ITO HIROSHI
NAKAMURA YUSUKE
MATSUDA YOJI
TSURUNO JIRO
YAMADA MASAYOSHI
ITO HIROSHI
NAKAMURA YUSUKE
MATSUDA YOJI
TSURUNO JIRO
Application Number:
JP2015153940A
Publication Date:
February 09, 2017
Filing Date:
August 04, 2015
Export Citation:
Assignee:
SEIKO EPSON CORP
International Classes:
H04R31/00; A61B8/14; H04R17/00
Attorney, Agent or Firm:
Kazuaki Watanabe
Keisuke Nishida
Satoshi Nakai
Keisuke Nishida
Satoshi Nakai
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