A measurement apparatus includes a sensor probe and a circuit housing. The sensor probe is insertable through an opening provided in a flow path wall of a flow path through which a fluid to be measured flows and is used in a predetermined orientation relative to the flow direction of the fluid to be measured. The circuit housing includes a display, disposed outside of the flow path, and connects to the sensor probe. The circuit housing is fixable at a plurality of rotation positions relative to the sensor probe about an axis along the insertion direction of the sensor probe. The measurement apparatus allows the display direction of the display to be selected regardless of the orientation of the sensor probe.

An apparatus for detecting one or more properties of a downhole fluid includes a housing. The apparatus also includes a location-sensitive optical detector, arranged within a chamber formed by the housing. The apparatus further includes a light source, arranged within the chamber. The apparatus also includes a lens, positioned at an end of the housing, the lens preferably having a flat side and a curved side, the flat side positioned proximate the chamber to position the flat side closer to the light source than the curved side. The apparatus further includes a mirror, arranged outside the housing.

An optical process sensor for measuring at least one measured variable of a medium in a container includes: a housing; a light source in the housing for emitting transmission light; a light detector in the housing for receiving reception light; and an interface including a first mechanical section, which is an integrated part of the housing, and a first optical section having a first path and a first light guide, wherein the first light guide is configured such that transmission light is guided from the light source into the first path via the first light guide and decouples transmission light from the housing, and having a second path and a second light guide, wherein the second light guide is configured such that reception light is coupled into the interior of the housing and guided from the second path to the light detector via the second light guide.

A spectroscopic assembly may include a spectrometer. The spectrometer may include an illumination source to generate a light to illuminate a sample. The spectrometer may include a sensor to obtain a spectroscopic measurement based on light, reflected by the sample, from the light illuminating the sample. The spectroscopic assembly may include a light pipe to transfer the light reflected from the sample. The light pipe may include a first opening to receive the spectrometer. The light pipe may include a second opening to receive the sample, such that the sample is enclosed by the light pipe and a base surface when the sample is received at the second opening. The light pipe may be associated with aligning the illumination source and the sensor with the sample.

A spectroscopic assembly may include a spectrometer. The spectrometer may include an illumination source to generate a light to illuminate a sample. The spectrometer may include a sensor to obtain a spectroscopic measurement based on light, reflected by the sample, from the light illuminating the sample. The spectroscopic assembly may include a light pipe to transfer the light reflected from the sample. The light pipe may include a first opening to receive the spectrometer. The light pipe may include a second opening to receive the sample, such that the sample is enclosed by the light pipe and a base surface when the sample is received at the second opening. The light pipe may be associated with aligning the illumination source and the sensor with the sample.

An in situ near infrared sensing unit includes a housing allowing the sensing unit to be inserted in a variety of media. A transparent window is formed in the sidewall of the housing. A sensing element is mounted inside the housing. The sensing element is configured to emit near infrared light provided from a light source external to the housing, and the sensing element is configured to collect near infrared light transmitted through the transparent window. A mirror is mounted in the housing at an angle with respect to the transparent window and opposite the sensing element. The angle allows the mirror to reflect the near infrared light, emitted by the sensing element, through the transparent window.

A method for determining contents of sample liquids spectrometrically includes an empty-state measurement with no liquid present, to obtain an empty-state light intensity measurement I.sub.e. A liquid-blank measurement is then taken of a pure unmixed volume of said liquid component, to obtain a liquid-blank light intensity measurement I.sub.w. A sample measurement of the sample liquid is then taken to obtain a sample light intensity measurement I.sub.s. Using I.sub.e, I.sub.w, and I.sub.s, determination is made of a volume concentration of a liquid component [H2O] in the sample liquid, and a liquid-corrected light intensity measurement I.sub.wc. From I.sub.s, I.sub.wc and a known length of the light path, a volume concentration of alcohol [Alc] is calculated. From [H2O] and [Alc], a remnant volume concentration attributable to other constituents is determined, from which a carbohydrate concentration [Carb] is calculated using a predetermined carbohydrate coefficient. Provisions for turbidity determination and light scatter correction are included.

An optical process sensor for measuring at least one measured variable of a medium in a container includes: a housing; a light source in the housing for emitting transmission light; a light detector in the housing for receiving reception light; and an interface including a first mechanical section, which is an integrated part of the housing, and a first optical section having a first path and a first light guide, wherein the first light guide is configured such that transmission light is guided from the light source into the first path via the first light guide and decouples transmission light from the housing, and having a second path and a second light guide, wherein the second light guide is configured such that reception light is coupled into the interior of the housing and guided from the second path to the light detector via the second light guide.

A spectroscopic assembly may include a spectrometer. The spectrometer may include an illumination source to generate a light to illuminate a sample. The spectrometer may include a sensor to obtain a spectroscopic measurement based on light, reflected by the sample, from the light illuminating the sample. The spectroscopic assembly may include a light pipe to transfer the light reflected from the sample. The light pipe may include a first opening to receive the spectrometer. The light pipe may include a second opening to receive the sample, such that the sample is enclosed by the light pipe and a base surface when the sample is received at the second opening. The light pipe may be associated with aligning the illumination source and the sensor with the sample.

An apparatus for detecting one or more properties of a downhole fluid includes a housing. The apparatus also includes a location-sensitive optical detector, arranged within a chamber formed by the housing. The apparatus further includes a light source, arranged within the chamber. The apparatus also includes a lens, positioned at an end of the housing, the lens preferably having a flat side and a curved side, the flat side positioned proximate the chamber to position the flat side closer to the light source than the curved side. The apparatus further includes a mirror, arranged outside the housing.