Abstract: The invention relates to a gas sensor having a mechanical microresonator, which has an excitation apparatus for optically exciting a mechanical oscillation of the microresonator as well as a reading apparatus for detecting the oscillation of the microresonator, wherein the reading apparatus comprises a waveguide which is implemented together with the microresonator on a dielectric or semiconducting substrate and is intended to optically read the oscillation of the microresonator, and wherein the excitation apparatus has an optical waveguide which is implemented on the same substrate and optically connects an excitation light source to the immediate surroundings of the microresonator. The invention also relates to a use of such a sensor to analyse a gas composition.

Abstract: An optical sensor for detecting a substance includes a first waveguide and a second waveguide optically coupled via a directional coupler to the first waveguide. The sensor has a functional surface in a region of the directional coupler for accumulating or storing the substance to be detected so that an intensity of a coupling arranged by the directional coupler between the first waveguide and the second waveguide can be changed by the accumulating or storing of this substance. The first waveguide extends in a freely floating manner over a coupling path covered by the directional coupler or rests on a swellable material. The first waveguide is guided in a vicinity of the coupling path so that a spacing between the first waveguide and the second waveguide can be changed there by a deformation or movement of the first waveguide or of a carrier of the first waveguide.

Abstract: The invention relates to a gas sensor having a mechanical microresonator, which has an excitation apparatus for optically exciting a mechanical oscillation of the microresonator as well as a reading apparatus for detecting the oscillation of the microresonator, wherein the reading apparatus comprises a waveguide which is implemented together with the microresonator on a dielectric or semiconducting substrate and is intended to optically read the oscillation of the microresonator, and wherein the excitation apparatus has an optical waveguide which is implemented on the same substrate and optically connects an excitation light source to the immediate surroundings of the microresonator. The invention also relates to a use of such a sensor to analyse a gas composition.

Abstract: An optical sensor for detecting a substance includes a first waveguide and a second waveguide optically coupled via a directional coupler to the first waveguide. The sensor has a functional surface in a region of the directional coupler for accumulating or storing the substance to be detected so that an intensity of a coupling arranged by the directional coupler between the first waveguide and the second waveguide can be changed by the accumulating or storing of this substance. The first waveguide extends in a freely floating manner over a coupling path covered by the directional coupler or rests on a swellable material. The first waveguide is guided in a vicinity of the coupling path so that a spacing between the first waveguide and the second waveguide can be changed there by a deformation or movement of the first waveguide or of a carrier of the first waveguide.