Electromechanical device with adjustable resonance frequency

An electromechanical device having an adjustable resonance frequency, comprising:

• a piezoelectric support delimited by a surface, or by two surfaces parallel to each other, and
• made on the piezoelectric support, a resonator for elastic waves propagating parallel to said surface or surfaces, the resonator comprising at least:
• two reflectors that delimit the resonator and which are reflective for said elastic waves,
• between the two reflectors, several interfacing transducers configured to generate said elastic waves from an electrical signal, and
• several tuning transducers for controlling said adjustable resonance frequency,
• each of said interfacing transducers comprising a first electrode and a second electrode that are interdigitated and each of said tuning transducers comprising a third and a fourth electrode that are interdigitated, each of said first, second, third and fourth electrodes made on said surface, or on one of said surfaces of the piezoelectric support, and
• an electrical device for controlling said adjustable resonance frequency, the electrical device comprising a first terminal and a second terminal and having between the first and second terminals an adjustable electrical impedance,
• wherein:
• for each tuning transducer, the third electrode and the fourth electrode of the tuning transducer are respectively connected to the first terminal and to the second terminal of said electrical control device,
• the first electrodes of the several interfacing transducers are electrically connected to each other, and the second electrodes of the interfacing transducers are also electrically connected to each other, and
• the interfacing transducers and the tuning transducers are positioned along a propagation path followed by said elastic waves in the resonator with an alternation between interfacing transducers and tuning transducers, each tuning transducer being inserted between two successive interfacing transducers, or between one of the reflectors and one of the interfacing transducers.