Patent ID: 8502625

Claim:
A surface acoustic wave resonator comprising: a quartz crystal substrate with an Euler angle of (−1.5°≦φ≦1.5°, 117°≦θ≦142°, 41.9°≦|ψ|≦49.57°); an IDT that is disposed on the quartz crystal substrate, that has a plurality of electrode fingers, and that excites a surface acoustic wave in an upper mode of an IDT stop band; and an inter-electrode-finger groove that is formed between the electrode fingers, wherein the following expression: 0.0407≦( G+H )/λ≦0.20 where λ represents a wavelength of the surface acoustic wave, H represents a thickness of a first electrode film of the electrode fingers and G represents a depth of the inter-electrode-finger groove, is satisfied.