An acoustic wave filter includes a filter circuit connected to input-and-output terminals, and a canceling circuit connected in parallel to at least a portion of a first path connecting the input-and-output terminals. The filter circuit includes one or more series-arm resonators on the first path, and one or more parallel-arm resonators between the first path and a ground. The canceling circuit includes acoustic wave resonators in parallel or substantially in parallel in a propagation direction of an acoustic wave. At least one of the acoustic wave resonators is connected to the ground, and an anti-resonant frequency of the at least one of the acoustic wave resonators is in a pass band of the filter circuit.

Disclosed herein is a tunable diffraction grating using surface acoustic waves. In some embodiments, the tunable diffraction grating includes a piezoelectric substrate including an interdigital transducer (IDT) region and a delay line region; a plurality of IDT electrodes positioned in the IDT region, wherein the IDT electrodes are each individually addressable such that the voltage applied to each of the electrodes is phase shifted, and wherein the IDT electrodes provide the phase shifted voltage to induce surface acoustic waves in the piezoelectric substrate in a pattern which produce a grating in the delay line region. Advantageously, tunable diffraction gratings have many applications including spectrometers for orbiters and rovers to Mars.

Disclosed herein is a tunable diffraction grating using surface acoustic waves. In some embodiments, the tunable diffraction grating includes a piezoelectric substrate including an interdigital transducer (IDT) region and a delay line region; a plurality of IDT electrodes positioned in the IDT region, wherein the IDT electrodes are each individually addressable such that the voltage applied to each of the electrodes is phase shifted, and wherein the IDT electrodes provide the phase shifted voltage to induce surface acoustic waves in the piezoelectric substrate in a pattern which produce a grating in the delay line region. Advantageously, tunable diffraction gratings have many applications including spectrometers for orbiters and rovers to Mars.

An acoustic wave filter includes a filter circuit connected to input-and-output terminals, and a canceling circuit connected in parallel to at least a portion of a first path connecting the input-and-output terminals. The filter circuit includes one or more series-arm resonators on the first path, and one or more parallel-arm resonators between the first path and a ground. The canceling circuit includes acoustic wave resonators in parallel or substantially in parallel in a propagation direction of an acoustic wave. At least one of the acoustic wave resonators is connected to the ground, and an anti-resonant frequency of the at least one of the acoustic wave resonators is in a pass band of the filter circuit.