A surface acoustic wave filter has a plurality of interdigital transducers arranged in a ladder circuit structure. Each of the interdigital transducers has a first comb-shaped electrode and a second comb-shaped electrode, each of which has a plurality of electrode fingers and a bus bar connected to first ends of the plurality of electrode fingers. The first and second comb-shaped electrodes interdigitate with each other so that second ends of the plurality of electrode fingers of the first comb-shaped electrode extend toward the bus bar of the second comb-shaped electrode. A gap is created in at least one of the interdigital transducers to cause a ripple in the pass band of the surface acoustic wave filter such that the ripple increases the steepness of the filter characteristics at the high frequency shoulder of the pass band. The gap is defined between the bus bar of the first comb-shaped electrode and the second ends of the plurality of electrode fingers of the second comb-shaped electrode. The gap width should be in the range of about 0.50 .lambda. to about 4 .lambda., wherein .lambda. is a wavelength of a surface acoustic wave to be excited on the piezoelectric substrate.

 
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