Laser-probe analysis of field distributions within acoustic-surface-wave planar resonators

Transverse boundary conditions can exert a marked influence on internal field configurations within an acoustic-surface-wave planar resonator. Laser-probe plots of field distributions within two ostensibly similar piezoshorting resonators are reported. The results provide some insight into the eigenmode spectrum of both the resonator and the multistrip coupler. It is proposed that planar resonator drive transducer apodisation may be used to reduce overmoding.