There is provided a gas sensing device for sensing a certain gas that is associated with a certain spectral band, the gas sensing device may include a passive gas sensor that is configured to generate passive gas sensor detection signals that are responsive to the certain spectral band; a passive dummy sensor that is configured to generate passive dummy sensor detection signals that are indifferent to the certain spectral band; and at least one circuit that is configured to detect a presence or absence of the certain gas within a certain volume that is located within the fields of view of the passive gas sensor and the passive dummy sensor based on a comparison between the passive gas sensor detection signals and the passive dummy sensor detection signals.

Device for improving an optical detecting smoke apparatus and implementing thereof. Apparatus and methods for detecting the presence of smoke in a small, long-lasting smoke detector are disclosed. Specifically, the present disclosure shows how to build one or more optimized blocking members in a smoke detector to augment signal to noise ratio. This is performed while keeping the reflections from the housing structure to a very low value while satisfying all the other peripheral needs of fast response to smoke and preventing ambient light. This allows very small measurements of light scattering of the smoke particles to be reliable in a device resistant to the negative effects of dust. In particular, geometrical optical elements, e.g., cap and optical defection elements, are disclosed.

The present disclosure relates to a device for measuring an optical absorption property of a fluid as function of wavelength. The device comprises a broadband light source for emitting light, a plurality of integrated optical waveguides for guiding this light, and a light coupler for coupling the emitted light into the integrated optical waveguides such that the light coupled into each integrated optical waveguide has substantially the same spectral distribution. The device also comprises a microfluidic channel for containing the fluid, arranged such as to allow an interaction of the light propagating through each waveguide with the fluid in the microfluidic channel. Each integrated optical waveguide comprises an optical resonator for filtering the light guided by the waveguide according to a predetermined spectral component. The spectral component corresponding to each waveguide is substantially different from the spectral component corresponding to another of the waveguides.

A method of identifying the presence of a first gas such as methane within a sample, for example containing natural gas. A detector is provided having a sensor responsive to a first wavelength, a sensor responsive to a second wavelength, and a sensor for collecting reference readings. A gas sample is analysed to obtain a first absorption reading corresponding to the first wavelength, a second absorption reading corresponding to the second wavelength and a reference reading. A first absorption figure is calculated using the first absorption reading and the reference reading, and a second absorption figure using the second absorption reading and the reference reading. The sensor for each wavelength is calibrated for detecting the first gas such that the data collected at each wavelength gives the same reading when only said first gas is present in a sample.

An integrated approach for cleaning an active surface of a petrochemical sensor. Sensors in the petrochemical industry are often deployed in locations where they are prone to fouling. By heating the active surface fouling substances may be removed from the active surface. Heating the surface above a supercritical point of a fluid being sensed may create a fluid that may serve to clean the active surface. Limiting the duration of the applied heating and/or pulsing the heating may mitigate adverse effects of use of high temperatures. A doped active surface, such as a doped diamond window may be designed to have conductive areas in the window that may be used for resistive heating of the window.

The present disclosure describes a device for measuring an optical absorption property of a fluid as function of wavelength. The device comprises a broadband light source for emitting light, a plurality of integrated optical waveguides for guiding this light and a light coupler for coupling the emitted light into the integrated optical waveguides such that the light coupled into each integrated optical waveguide has substantially the same spectral distribution. The device also comprises a microfluidic channel for containing the fluid, arranged such as to allow an interaction of the light propagating through each waveguide with the fluid in the microfluidic channel, and a plurality of spectral analysis devices optically coupled to corresponding waveguidessuch as to receive the light after interaction with the fluid. The spectral analysis devices are adapted for generating a signal representative of a plurality of spectral components of the light.

A portable device for detecting and/or quantifying hemozoin by optical reflectance spectrophotometry, directly on the patient's skin, on tissues or in a liquid sample which comprises means for calibrating the device; at least one optical emitter to excite the sample; at least eight optical detectors to detect the reflectance spectrum of the sample; at least eight bandpass optical filters to filter the reflected light for each optical detector; wherein the optical filters and optical detectors are aligned with each other, wherein the emitter and optical detectors are positioned allowing reflection of the emitted light towards the optical detectors, wherein the optical filters and optical detectors comprise wavelengths between 400 nm and 800 nm; and a microcontroller configured to calculate a ratio between the reflectance values of the sample at each wavelength to detect the reflectance peaks. Also disclosed is a method of detecting and/or quantifying hemozoin by optical reflectance spectrophotometry.

Measuring device (1) for analyzing a respiratory gas flow, comprising at least one measuring unit (4) and a cuvette (5), the cuvette (5) being releasably connected to the measuring unit (4) and being adapted and configured so that a respiratory gas flows through said cuvette, the measuring unit (4) having at least two sensor units (41, 42), at least one sensor unit (41) being configured to determine a respiratory gas flow and at least one sensor unit (42) being configured to determine a CO2 concentration in a respiratory gas, and the cuvette (5) comprising at least two sensor connections (51, 52) for connecting the sensor units (41, 42) for determining at least one respiratory gas flow and at least one CO2 concentration of a respiratory gas.

The invention is directed to a multi-wavelength process photometer (20) for quasi-continuously determining the absorption of a liquid sample, comprising a continuous-spectrum flashlight source (24), a transparent liquid sample measurement cell (40) which is radiated by the flashlight source (24), a translucent light diffusor element (50) behind the measurement cell (40) for homogenously diffusing the light of the flashlight source (24) coming from the liquid sample measurement cell (40), and at least two different wavelength-selective light detectors (61, 62, 63) behind the light diffusor element (50), wherein the light detectors (61, 62, 63) have substantially the same distance (X4) to the light diffusor element (50).

A device (1) for determining the concentration of a gas component is configured with a radiation source (30) for emitting (31) a light radiation or heat radiation in an infrared wavelength range. A detector array (40) has at least two detector elements (50, 60), configured to detect the radiation generated by the radiation source (30), in an angular arrangement (52, 62) and with filter elements (51, 61). At least one of the two detector elements (50, 60) is oriented in an angular arrangement (52, 62) in relation to a vertical axis (32), so that a range of overlap (65) is obtained due to the angular arrangements (52, 62). The range of overlap (65) causes attenuations in the propagation of light, which attenuations may be due, for example, to gas molecules or moisture (400), affect both detector elements (50, 60) and are thus compensated concerning the concentration determination.