The present invention provides a system for measuring concentrations of trace gases in gas mixtures using the absorption spectroscopy method. The system comprising an optical cell containing a gas mixture, a continuous-wave tunable laser, a detector system for measuring an absorption of laser light by the gas in the optical cell, and a processor to conduct an absorption spectroscopy analysis of the gas mixture based on light intensity measured by the detector system at one or more laser frequencies.

A method of suppressing retroreflector fringe noise in TDL spectrometers (TDLS) that use a laser and retroreflector. The path between the laser and each retroreflector element is changed mechanically for example by using a movable support for the retroreflector. The phase of light reaching the retroreflectors is very sensitive to the pathlength. A pathlength change of a fraction of the light wavelength will significantly change the phase of the light. In this method the pathlength to each retroreflector is modulated by mechanical means and this modulation is both stronger and faster than atmospheric effects on phase. If mechanical modulation occurs at a sufficiently high frequency retroreflector fringe noise can be averaged by integration of the spectrometer output over a reading period of typically one second.

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.

An analyzer of a component in a sample fluid includes an optical source and an optical detector defining a beam path of a beam, wherein the optical source emits the beam and the optical detector measures the beam after partial absorption by the sample fluid, a fluid flow cell disposed on the beam path defining an interrogation region in the a fluid flow cell in which the optical beam interacts with the sample fluid and a reference fluid; and wherein the sample fluid and the reference fluid are in laminar flow, and a scanning system that scans the beam relative to the laminar flow within the fluid flow cell, wherein the scanning system scans the beam relative to both the sample fluid and the reference fluid.

A method is provided for detecting a property of a gas comprising: emitting a light, comprising a plurality of wavelengths covering a plurality of absorption lines of the gas, along a first axis, the light being scattered by particles of the gas resulting in a scattered light, generating a sensor image using a detection arrangement configured to receive the scattered light and comprising: an optical arrangement having an optical plane and being configured to direct the scattered light on to a light sensor, the light sensor having at least one pixel columns, wherein the pixel columns are aligned to an image plane and configured to output a sensor image, wherein the first axis, the optical plane, and the image plane intersect such that a Scheimpflug condition is achieved, determining, from the sensor image, properties of the gas at a plurality of positions along the first axis.

There is described an infrared spectrometer having an optical circuit which comprises one or more hollow waveguides provided by elongate channels formed in a substrate. The optical circuit is arranged such that infrared light in the optical circuit acquires one or more spectral properties for detection by the spectrometer. A laser source couples laser light into an input hollow waveguide portion of the optical circuit, and an optical detector receives the light from an output hollow waveguide portion of the optical circuit, so that an analyser can determine said one or more spectral properties from the detected light.

Apparatuses, systems, and methods for open path laser spectroscopy with mobile platforms. An example system may include a first mobile platform and a second mobile platform, each of which supports a payload. A light beam directed from one payload to another may define a measurement path, which may be at a particular height above the ground. The payloads may determine a gas concentration along the measurement path. Wind information at the measurement height may be used to determine a gas flux. One or both of the mobile platforms may then move to a new location, and take a measurement along a new measurement path. By combining the measurement paths, gas flux through a flux surface may be determined.

Systems and method for analysing contaminants of a gas sample of natural gas are provided. An interrogation light beam propagates into a chamber of a multipass gas cell receiving the gas sample. The interrogation light beam has a wavelength controlled to alternately correspond to an absorption wavelength of H.sub.2S and an absorption wavelength of an additional gas contaminant. The additional gas contaminant may for example be CO.sub.2 or H.sub.2O. In some implementation, a single laser emitter may be used to generate the interrogation light beam at the H.sub.2S and CO.sub.2 wavelengths. In some implementations, two different laser emitters may be used to generate the interrogation light beam at the H.sub.2S and H.sub.2O wavelengths. A WMS detection scheme may be used.

The invention relates to a test device (10) for analysing, more particularly for detecting, non-destructively, pressure and temperature, and preferably for detecting a gas concentration in foodstuffs (50.4) contained in packaging (50), the test device having: —a detection assembly (30) for detecting at least one parameter in a foodstuff (50.4) contained in packaging (50), the parameter being specific to a property to be examined of the foodstuff (50.4). According to the invention, the test device (10) is designed as a hand-held device.

An optical system measures one or more physiological parameters with a wearable device that includes a light emitting diode (LED) source including a driver and a plurality of semiconductor sources that generate an output optical light. One or more lenses deliver a lens output light to tissue of a user. A detection system receives at least a portion of the lens output light reflected from the tissue and generates an output signal having a signal-to-noise ratio. The detection system comprises a plurality of spatially separated detectors and an analog to digital converter. The detection system increases the signal-to-noised ratio by comparing a first signal with the LEDs off to a second signal with the LEDs on. An imaging system including a Bragg reflector is pulsed and has a near infrared wavelength. A beam splitter splits the light into a sample arm and a reference arm to measure time-of-flight.