Multi-reflective acoustic wave device

A multi-reflective acoustic wave device comprising:

• a substrate having at least one layer of piezoelectric substance having at least a first surface capable of guiding an acoustic wave, and at least a second surface opposite to said first surface;
• an electromechanically significant reflective grating deposited on said first surface having a length along its longitudinal axis, said length defining longitudinal extents of an area supporting acoustic waves, wherein said active area is covered on at least 60% of its longitudinal dimension by electromechanically active transducer elements of said reflective grating, said elements being spaced at substantially periodic intervals commensurating with the wavelength of said acoustic wave;
• the electromechanically active transducer elements forming an input transducer, and an output transducer, each transducer integrated into said reflective grating, and comprising a plurality of interdigitated electrodes connected in a periodic sequence to a plurality of electrical nodes;
• said input transducer adapted to induce an acoustic waves, said acoustic wave having a frequency and a vector substantially perpendicularly to said electrodes and in the plane of said first surface;
• wherein said reflective grating is locally continuous and periodic, and constructed to create an electromechanically significant reflective coupling between the forward and a reverse traveling acoustic wave induced in the piezoelectric substance.