According to one embodiment, a gas analysis device includes: a base including a concave portion; a window includes a first film and a second film; an optical part that is located at a side of the window opposite to the base side and includes a light projector and a light receiver; and an optical path length controller that is located between the base and the window and has a controllable thickness. The concave portion includes a first sidewall that is oblique to a surface of the base, and a second sidewall that is oblique to the surface of the base. An oblique direction of the second sidewall is opposite to an oblique direction of the first sidewall. The light projector is configured to irradiate light toward the first sidewall. The light receiver is configured to convert light reflected by the second sidewall.

A sample cell apparatus for use in spectroscopic determination of an analyte in a body fluid sample includes a first plate member made from an optically clear material and a second plate member made from an optically clear material and opposing the first plate member. A channel extending into a surface of the first plate member and an opposing surface of the second plate member houses a floating seal. The floating seal surrounds a fluid chamber that retains a sample of body fluid for optical measurement. The fluid chamber may be opened for flushing by separating the first plate member from the second plate member. During measurements the fluid chamber is closed to define a repeatable optical path-length therethrough by urging the first plate member against the second plate member without compressing the floating seal between the first plate member and the second plate member.

An optical cell comprises first and second opposed reflecting elements, an entrance aperture in the first reflecting element and an exit aperture in the second reflecting element, wherein the entrance and exit apertures are configured such that, in operation, light introduced into the cell via the entrance aperture is reflected at least once by the second reflecting element and at least once by the first reflecting element before leaving the cell via the exit aperture.

The present invention relates generally to a slope spectroscopy standards and methods of making slope spectroscopy standards, specifically standards and methods of developing standards specifically for variable pathlength (slope) measurements.

An optical density testing system includes a light source, a first light splitting device used to divide the light into at least two light paths, at least two second light splitting devices used for receiving the at least two paths of light from the first light splitting device, first light-passing holes provided corresponding to each of the at least two second light splitting devices, a first filter device detachably arranged at each of the first light-passing holes, a first diaphragm detachably installed on each of the first filter devices, and a light receiving device. The second light splitting device is used to transmit the light onto a product to be tested through the first filter device and the first diaphragm. The light receiving device is used to receive transmitted light formed after the light passes through the product to be tested.

Gas analyzer or gas analysis method, in which beams of at least two different radiation sources are coupled into a Herriott cell containing a measurement gas and, after being reflected multiple times, are coupled out therefrom and detected, wherein the beams are aligned such that they strike mirrors in point patterns which extend along ellipses, where the different ellipses lie inside one another and have two shared vertices (co-vertices) on a shared axis of symmetry, whereas the other co-vertices (or vertices) do not coincide, the beams of at least two of the different radiation sources are coupled into the Herriott cell at differing points of the associated point pattern and/or are coupled into the Herriott cell such that they pass through the associated point patterns along the ellipses in opposite directions, and where all beams are coupled out at the point of one of the shared vertices.

A flow cell system for an optical fluid analysis comprises a disposable flow cell having at least one flow chamber comprising a fluid pathway, and at least one pair of opposed light transmitting windows along the fluid pathway, an external flow cell holder for holding the flow cell, at least one light source, and an external detection device couplable with at least one of the flow cell holder and the flow cell for bringing the external detection device in optical communication with the flow cell, the device having at least one optical detection unit. The external detection device is configured to conduct optical measurements of the fluid that flows in the flow cell through at least one pair of windows from externally under illumination by the at least one light source.

An optically thin sample of a sample material is analyzed by propagating probe electromagnetic radiation from a beam source along a plurality of different ray paths, directing each ray so that each ray path intersects upon the sample at a plurality of different locations where the rays interact with the sample material to cause a modification of the ray. The rays received at each of a plurality of detection spatial region are measured separately and the measurements analyzed to provide information about at least one property of the sample material at each interaction location. An analysis is carried out to trace the path of probe radiation from a location at the probe beam source to the detection spatial region on the detection surface so as to identify the interaction locations so as to provide information about the presence of target material at each interaction location.

Disclosed are methods of determining the suitability of a variable-length spectrophotometer using Patent Blue dye or AMG Blue dye. Also disclosed herein are methods of determining the suitability of a fixed path length spectrophotometer for determining protein concentration of a protein sample. AMG Blue dye may also be used to determine the suitability of fixed path length spectrophotometers.

A device for measuring the flocculation threshold of a colloidal medium, and a method for measuring the flocculation threshold of a colloidal medium by the addition of aliphatic solvent using the device, including the step of determining the flocculation after the addition of the amount of aliphatic solvent necessary for flocculation.