Patent ID: 8791621

Claim:
A surface acoustic wave resonator comprising: a quartz crystal substrate with Euler angles (−1.5°≦φ≦1.5°, 117°≦θ≦142°, and 42.79°≦|Ψ|≦49.57°); an IDT that is provided on the quartz crystal substrate, that includes a plurality of electrode fingers, and that excites a stop band upper end mode surface acoustic wave; and inter-electrode finger grooves that are provided in the quartz crystal substrate between the electrode fingers in a plan view, wherein when a wavelength of the surface acoustic wave is λ, a first film thickness of the electrode finger is H, and a first depth of the inter-electrode finger groove is G, and when a line occupation rate of convex portions of the quartz crystal substrate disposed between the inter-electrode finger grooves is ηg, and a line occupation rate of the electrode fingers disposed on the convex portions is ηe, the following relationships are satisfied: 0.0407 λ≦G+H ; and η g>ηe.