Patent ID: 7352104

Claim:
A surface acoustic wave element comprising: an in-plane rotated ST cut quartz plate whose cutting angle is expressed as (0°, 113°-135°(40°-49°)) by defining and using Euler angle of (φ°,θ°,Ψ°); an interdigital transducer; and a reflector, wherein: the interdigital transducer and the reflector that are formed on a surface of the quartz plate are arranged at a slant of a PFA ±3° with respect to a direction of a phase velocity of a surface acoustic wave in the quartz plate; the PFA is represented by the following equation: PFA =0.374(θ°−90°)−10.0°; and first and second opposing edges of the ST cut quartz plate are substantially parallel to a group velocity direction of the surface acoustic wave element.