Measuring device

A measuring device comprising:

• a substrate;
• a first piezoelectric element and a second piezoelectric element provided on the substrate;
• and
• a protective layer covering the first piezoelectric element and the second piezoelectric element, wherein
• the first piezoelectric element includes a first lower electrode provided on the substrate, a first piezoelectric layer provided on the first lower electrode, a first upper electrode provided on the first piezoelectric layer, and an expansion/contraction suppression layer provided on the substrate so as to cover the first upper electrode, the first piezoelectric layer, and the first upper electrode,
• the second piezoelectric element includes a second lower electrode provided on the substrate, a second piezoelectric layer provided on the second lower electrode, and a second upper electrode provided on the second piezoelectric layer, and
• the expansion/contraction suppression layer has a higher modulus of elasticity than the first piezoelectric layer and the protective layer.

A measuring device comprising:

• a first piezoelectric element and a second piezoelectric element;
• and
• a piezoelectric layer provided in common for the first piezoelectric element and the second piezoelectric element, and which includes a first partial piezoelectric layer and a second partial piezoelectric layer;
• wherein
• the first piezoelectric element includes a first lower electrode, the first partial piezoelectric layer provided on the first lower electrode, a first upper electrode provided on the first partial piezoelectric layer, and an expansion/contraction suppression layer provided on the first partial piezoelectric layer so as to cover the first upper electrode,
• the second piezoelectric element includes a second lower electrode, the second partial piezoelectric layer provided on the second lower electrode, and a second upper electrode provided on the second partial piezoelectric layer,
• the expansion/contraction suppression layer has a higher modulus of elasticity than the piezoelectric layer,
• the measuring device further comprises a first protective layer provided on the piezoelectric layer so as to cover the expansion/contraction suppression layer and the second upper electrode,
• the piezoelectric layer has flexibility or an expansion/contraction property,
• the piezoelectric layer is formed of an organic piezoelectric material having an expansion/contraction property, and
• the measuring device further comprises a second protective layer provided on a bottom surface of the piezoelectric layer so as to cover the first lower electrode and the second lower electrode.