A detector cell for a photoacoustic gas sensor comprises a first layer structure, a second layer structure arranged at the first layer structure and comprising a membrane structure, and a third layer structure arranged at the second layer structure. The first layer structure and the third layer structure hermetically enclose a cavity, wherein the membrane structure is arranged in the cavity.

The invention relates, in a first aspect, to a photoacoustic spectroscope for analyzing gas, comprising an infrared emitter (3), which can be modulated, an analysis volume (1), which can be filled with gas, and a sound pressure detector. The sound pressure detector comprises a structure (5) capable of vibrating, an actuator and a measurement unit, wherein the actuator is configured to actively excite vibration of the structure (5) capable of vibrating and the measurement unit can measure the vibration properties of the structure (5) capable of vibrating, which measurement depends on the formation of the sound pressure waves.

In an additional aspect, the invention relates to a method for analyzing gas, comprising the provision of a photoacoustic spectroscope for analyzing gas, irradiating the gas with infrared radiation, modulated by a modulation frequency, to generate sound pressure waves, exciting the structure (5) capable of vibrating at an excitation frequency, measuring the vibration properties of the structure (5) capable of vibrating, which measurement depends on the sound pressure, and determining the sound pressure of the gas based on the measured vibration properties.

The present disclosure relates to a photoacoustic gas sensor for detecting the presence or absence of gas using the interaction of a laser beam and gas molecules. The integrated photoacoustic gas sensor according to an embodiment includes a light output unit; a lens unit configured to concentrate a laser beam output from the light output unit; and a photoacoustic sensing unit having a quartz tuning fork aligned on the lens unit and configured to convert a vibration, generated when the laser beam passing through the lens unit interacts with gas molecules, into an electric signal.

A detector comprises an optical parametric oscillator having a non-linear material adapted to convert via a parametric process pump light into down converted light of two different wavelengths, the first wavelength being longer than the second wavelength. The non-linear material is provided in a down converted wave cavity arranged to resonate only one of the first or second wavelengths. The detector comprises means for modulating light in the down converted wave cavity to induce an acoustic or pressure wave caused by absorption of the resonant one of the first and second wavelengths. The detector further comprises means located in the down-converted wave cavity for detecting the acoustic or pressure wave. The detector may be used for detecting or sensing very low levels of a fluid, for example a gas such as ethane.

A photoacoustic gas sensor device is proposed for determining a value indicative of a presence or a concentration of a component in a gas. The photoacoustic gas sensor device comprises a substrate, and a measurement cell body arranged on a first side of the substrate. The substrate and the measurement cell body define a measurement cell enclosing a measurement volume. The measurement cell comprises an aperture for a gas to enter the measurement volume. The device further comprises an electromagnetic radiation source for emitting electromagnetic radiation, and a microphone for measuring a sound wave generated by the component in response to an absorption of electromagnetic radiation by the component. The electromagnetic radiation source and the microphone are arranged on the first side of the substrate and in the measurement volume. The microphone has a bottom port facing the substrate, and the measurement volume is communicatively coupled to the bottom port.

A photoacoustic detection system (20) includes a detector (22) that has a chamber (24), a pulsed light source (26), piezoelectric tuning forks (28), and a photosensor (30). The chamber has an inlet and an outlet for flow of an analyte. The pulsed light source is adjacent the chamber and is operable to emit a light beam along a path through the chamber. The tuning forks are arranged along the path, and each of the tuning forks is operable to emit first sensor signals. The photosensor is arranged along the path and is operable to emit second sensor signals. A controller (38) is connected to receive the first and second sensor signals. The controller is configured to determine whether a target species is present in the analyte based on the first sensor signals and determine whether the target species is present in the analyte based on the second sensor signals.

The present disclosure relates to a photoacoustic gas sensor for detecting the presence or absence of gas using the interaction of a laser beam and gas molecules. The integrated photoacoustic gas sensor according to an embodiment includes a light output unit; a lens unit configured to concentrate a laser beam output from the light output unit; and a photoacoustic sensing unit having a quartz tuning fork aligned on the lens unit and configured to convert a vibration, generated when the laser beam passing through the lens unit interacts with gas molecules, into an electric signal.

Disclosed are a photo-acoustic sensor device and a photo-acoustic sensing method of the same. The sensing method includes providing a source light in a subject and receiving an ultrasonic wave generated in the subject by the source light. The source light may have a wavelength of 1400 nm to 2500 nm in a near-infrared band.

In a first aspect, the invention relates to a photoacoustic gas sensor comprising a gas-fillable detection chamber and a reference chamber arranged laterally adjacent to each other and connected by a sensor channel. A sensor located at or in the sensor channel allows measurement of the photoacoustic signals. Both chambers are preferably located in a plane perpendicular to the emitted IR radiation of the IR emitter which is also comprised. The gas sensor is also formed from a multilayer substrate.

In further aspects, the invention also relates to a method of manufacturing a gas sensor and a method of analyzing gas with a gas sensor.

A detector cell for a photoacoustic gas sensor comprises a first layer structure, a second layer structure arranged at the first layer structure and comprising a membrane structure, and a third layer structure arranged at the second layer structure. The first layer structure and the third layer structure hermetically enclose a cavity, wherein the membrane structure is arranged in the cavity.