Patent ID: 7211936

Claim:
A resonator piece, including: a base portion in which a first and a second base portion electrode portions are formed; a first and a second resonating arm portions formed so as to project from the base portion; a first groove portion including a first groove electrode portion formed in front surfaces of the first resonating arm portion; a second groove portion including a second groove electrode portion formed in front surfaces of the second resonating arm portion; a first side surface electrode portion formed in inner side surfaces of the first resonating arm portion; a second side surface electrode portion formed in outer side surfaces of the second resonating arm portion; a side surface electrode-use connection electrode portion that connects the first base portion electrode portion with the first side surface electrode portion, wherein a width of the base portion side of openings of the first groove portion is formed narrower than a width of other portions, wherein a connection electrode disposition portion for disposing the side surface electrode-use connection electrode portion is formed adjacent to narrowly formed openings of the first groove portion, wherein the first base portion electrode portion is connected to the second groove electrode portion, and wherein the second base portion electrode portion is connected to the first groove electrode portion and the second side surface electrode portion.