Patent ID: 7691286

Claim:
A piezoelectric ceramic composition comprising: a primary component represented by the formula (1-x)(K 1-a-b Na a Li b ) m (Nb 1-c-d Ta c Sb d )O 3 -xM1 n M2O 3 ; and 0.1 to 10 moles of at least one element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu with respect to 100 moles of the primary component, wherein M1 represents at least one metal element selected from the group consisting of Ca, Sr, and Ba, and M2 represents at least one metal element selected from the group consisting of Ti, Zr, and Sn, and x, a, b, c, d, m, and n satisfy 0.005≦x≦0.1, 0≦a≦0.9, 0≦b≦0.3, 0≦a+b≦0.9, 0≦c≦0.5, 0≦d≦0.1, 0.9≦m≦1.1, and 0.9≦n≦1.1, respectively, wherein said composition has a piezoelectric d 33 constant of at least 200 pC/N in a high electric field of 1kV/mm.