Patent ID: 8354038

Claim:
A piezoelectric solid solution composition comprising, as a main component, a composition represented by the following general formula: {M x (Na y Li z K 1-y-z ) 1-x } 1-m {(Ti 1-u-v Zr u Hf v ) x (Nb 1-w Ta w ) 1-x }O 3 , wherein M represents a combination of at least one member selected from the group consisting of (Bi 0.5 K 0.5 ), (Bi 0.5 Na 0.5 ) and (Bi 0.5 Li 0.5 ) and at least one member selected from the group consisting of Ba, Sr, Ca and Mg; and x, y, z, u, v, w and m are in the following ranges: 0.06<x≦0.3, 0≦y≦1, 0≦z≦0.3, 0≦(y+z)≦1, 0.6≦u≦0.75, 0≦v≦0.75, 0≦w≦0.2, 0<(u+v)<1 and −0.06≦m≦0.06, wherein the piezoelectric solid solution composition has a rhombohedral-tetragonal morphotropic phase boundary.