Abstract: A method and an optical device in all-optical signal processing. It provides a novel way of taking into use the potential bandpass filtering capabilities of an optical complex one-pole resonator by, 1) excitating with at least part of the input signal an optical resonator arrangement that comprises two substantially parallel, independent, complex one-pole resonators arranged in a manner that one of the resonators is matched, and the other one is non-matched with the input signal, and 2) based on polarization separating further from the output of the optical resonator arrangement at least one optical output signal so that both the matched and non-matched resonators contribute to the formation of the output signal. The method and device can be utilized, for example, for optical signal analysis, optical clock recovery, or for producing high-frequency outputs from lower frequency input signals, like e.g. optical microwave generation.

Abstract: A device for processing of an optical input signal includes at least a first data signal. A first optical resonator provides a reference signal by optical filtering of the optical input signal. The first optical resonator is matched with a predetermined reference wavelength of the first data signal. A second optical resonator provides a sideband signal by optical filtering of the optical input signal. The second optical resonator is non-matched with the predetermined reference wavelength of the first data signal. An optical combiner combines the sideband signal with the reference signal to form an optical output signal.

Abstract: This publication discloses an acoustically active element formed in a multi-layer circuit-board structure (20, 22, 24, 25), a method for manufacturing it, and a multi-layer circuit-board structure. The acoustically active element includes an internal chamber (21) and a membrane (18) or beam arranged in connection with the internal chamber (21), which acts as a vibrating element and is connected electrically to external circuits, in order to produce or measure an acoustic effect. According to the invention, the resonance chamber (21) is formed inside the multi-layer circuit-board structure (20, 22, 24, 25), in connection with the process of manufacturing the circuit board.