A gas sensor device (100) is configured to measure a predetermined gas of interest and comprises an enclosure (101) comprising a semiconductor substrate (102) and defining a first cavity (124), an optically transmissive second closed cavity (126) and a third cavity (128). The second cavity (126) is interposed between the first and third cavities (124, 128). The first cavity (124) comprises an inlet port (130) for receiving a gas under test, an outlet port (132) for venting the gas under test. The first cavity (124) also comprises an optical source (112) and a measurement sensor (114). The second cavity (126) is configured as a gaseous filter comprising a volume of the gas of interest sealingly disposed in the second cavity (126), and the third cavity (128) comprises a reference measurement sensor (116) disposed therein.

Methods and apparatus are provided for determining the refractive index of a downhole fluid. Two unalike crystals are provided having faces in contact with fluid in the fluid flow line of a borehole tool. The crystals are chosen to have different refractive indices and/or different angles of incidence, but to provide total internal reflection for light that is directed through the crystals to the crystal/fluid interface. The measured attenuations for each crystal are used in conjunction with the known refractive indices and angles of incidence of said crystals to determine the refractive index of the fluid.

A gas sensor device (100) is configured to measure a predetermined gas of interest and comprises an enclosure (101) comprising a semiconductor substrate (102) and defining a first cavity (124), an optically transmissive second closed cavity (126) and a third cavity (128). The second cavity (126) is interposed between the first and third cavities (124, 128). The first cavity (124) comprises an inlet port (130) for receiving a gas under test, an outlet port (132) for venting the gas under test. The first cavity (124) also comprises an optical source (112) and a measurement sensor (114). The second cavity (126) is configured as a gaseous filter comprising a volume of the gas of interest sealingly disposed in the second cavity (126), and the third cavity (128) comprises a reference measurement sensor (116) disposed therein.

A measuring device for measuring a measurand of a medium includes a measuring cell, a measuring cell receptacle for holding the measuring cell, and a measuring apparatus for measuring the measurand, wherein the measuring cell includes a measurement chamber containing the medium and a reference chamber separate from the measurement chamber and containing a reference medium. The measurement chamber and the reference chamber are arranged relative to one another such that the measuring cell can be inserted into the measuring cell receptacle in a measuring position, in which measurements of the measurand of the medium can be performed by means of the measuring apparatus, and can be inserted into the measuring cell receptacle in a reference position, in which reference measurements of a reference variable of the reference medium in the reference chamber can be performed by means of the measuring apparatus.

Methods and apparatus are provided for determining the refractive index of a downhole fluid. Two unalike crystals are provided having faces in contact with fluid in the fluid flow line of a borehole tool. The crystals are chosen to have different refractive indices and/or different angles of incidence, but to provide total internal reflection for light that is directed through the crystals to the crystal/fluid interface. The measured attenuations for each crystal are used in conjunction with the known refractive indices and angles of incidence of said crystals to determine the refractive index of the fluid.

A method for sensing Hydrogen Sulfite by a gas sensor, the method may include receiving, by first aperture of a sphere of the gas sensor, a light beam; wherein the sphere further comprises a second aperture and a first gas opening; scattering multiple times, by an interior of the sphere, the light beam to provide a scattered light beam that exits the sphere through the second aperture; receiving, by a gas analyzer of the gas sensor, the scattered light beam from the second aperture; and analyzing the scattered light beam by searching for one or more signs that are indicative of a presence of the Hydrogen Sulfite in the sphere.

The present describes a system and method for determining the concentration of tetrahydrocannabinol (THC) including a tray comprising a first analyte including an infusion of a solvent and cannabis, a light emitting element configured to illuminate the first analyte, a light receiving element configured to receive a first light transmitted through the first analyte, and a control circuit configured to calculate a concentration of tetrahydrocannabinol in the first analyte based at least in part on the first light.

The present disclosure relates to a device for monitoring a light source of an optical sensor designed for determining a measured value of a measured parameter in a medium, including at least one light source for transmitting light along an optical path through a measuring chamber fillable with the medium, wherein the light source is associated with a receiver for receiving reception light, and at least one monitoring unit associated with the light source, with a sensory unit for monitoring the light source, wherein the monitoring unit receives transmission light, and wherein the sensory unit points in the direction of the optical path and receives light from the direction opposite the optical path. The present disclosure also relates to the use of such a device in an analyzer.

A measuring device for measuring a measurand of a medium includes a measuring cell, a measuring cell receptacle for holding the measuring cell, and a measuring apparatus for measuring the measurand, wherein the measuring cell includes a measurement chamber containing the medium and a reference chamber separate from the measurement chamber and containing a reference medium. The measurement chamber and the reference chamber are arranged relative to one another such that the measuring cell can be inserted into the measuring cell receptacle in a measuring position, in which measurements of the measurand of the medium can be performed by means of the measuring apparatus, and can be inserted into the measuring cell receptacle in a reference position, in which reference measurements of a reference variable of the reference medium in the reference chamber can be performed by means of the measuring apparatus.

An inspection system includes an inspection image acquirer, a spectrum corrector, a spectrum determiner, and a result output. The inspection image acquirer is configured to acquire an inspection target image. The inspection target image is obtained by imaging an object including an inspection target and a background in four or more wavelength ranges. The spectrum corrector is configured to make a correction based on a spectrum of an image of the background to a first spectrum to generate a second spectrum. The first spectrum is a spectrum of an image of the inspection target in the inspection target image. The spectrum determiner is configured to determine, based on the second spectrum, whether or not the inspection target is a first substance.