TUNING-FORK TYPE CRYSTAL VIBRATOR

PROBLEM TO BE SOLVED: To provide a tuning-fork type crystal vibrator in which reduction in electric field efficiency accompanying miniaturization or thinning is prevented and which is capable of having a peak temperature in the vicinity of a desired temperature.SOLUTION: A tuning-fork type crystal vibrator 11 comprises: a pair of vibrating arms 13, 14 extending from a base; grooves 15, 16 recessed in a length direction of the vibrating arms 13, 14; walls 17, 18 forming the grooves 15, 16; and exciting electrodes 19, 20 provided on surfaces of the walls 17, 18. When a linear function is used for approximating a first-order term temperature coefficient of a Young's modulus of the exciting electrodes 19, 20, a first-order term coefficient is denoted by A, a zero-order term coefficient is denoted by B, a room temperature is denoted by T and a Taylor expansion temperature is denoted by T, the temperature characteristics of the exciting electrodes 19, 20 are represented by E(T)=A(T-T)+B. When the minimum thickness of the walls 17, 18 is 6 μm or less and under the condition of A>-20 MPa/°C, a thickness of the exciting electrodes 19, 20 opposed to at least one of the walls 17, 18 is 1/50 or less as thick as the minimum thickness of the walls 17, 18.