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.

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.

An illuminator/collector assembly can deliver incident light to a sample and collect return light returning from the sample. A sensor can measure ray intensities as a function of ray position and ray angle for the collected return light. A ray selector can select a first subset of rays from the collected return light at the sensor that meet a first selection criterion. In some examples, the ray selector can aggregate ray intensities into bins, each bin corresponding to rays in the collected return light that traverse within the sample an estimated optical path length within a respective range of optical path lengths. A characterizer can determine a physical property of the sample, such as absorptivity, based on the ray intensities, ray positions, and ray angles for the first subset of rays. Accounting for variations in optical path length traversed within the sample can improve accuracy.

A method for implementation by a laser spectrometer is provided. The method includes first scanning, by a control unit using a first set of laser spectrometer operating parameters, a first wavelength range by adjusting a wavelength of light of a beam emitted by a laser light source and passing through a sample gas. The first wavelength range encompasses a first spectral feature corresponding to a first constituent. The method also includes at least one second scanning, by the control unit using a second set of laser spectrometer operating parameters, a second wavelength range by adjusting the wavelength of light emitted from the laser light source and passing through the sample gas. The second wavelength range has a second spectral feature corresponding to at least one second constituent. The control unit also determines a first concentration of the first constituent and a second concentration of the at least one second constituent.

An electrically modulated light source is provided. The electrically modulated light source comprises a carbon nanotube film structure. The electrically modulated light source heats up to a highest temperature and emits thermal radiation in less than 10 milliseconds after a voltage is applied, and the electrically modulated light source cools down to an initial temperature of the electrically modulated light source in less than 10 milliseconds after the voltage is removed. An modulation frequency of the electrically modulated light source is greater than or equal to 150 KHz. A non-dispersive infrared spectrum detection system used the electrically modulated light source, and a method for detecting gas used the electrically modulated light source are also provided.

An illuminator/collector assembly can deliver incident light to a sample and collect return light returning from the sample. A sensor can measure ray intensities as a function of ray position and ray angle for the collected return light. A ray selector can select a first subset of rays from the collected return light at the sensor that meet a first selection criterion. In some examples, the ray selector can aggregate ray intensities into bins, each bin corresponding to rays in the collected return light that traverse within the sample an estimated optical path length within a respective range of optical path lengths. A characterizer can determine a physical property of the sample, such as absorptivity, based on the ray intensities, ray positions, and ray angles for the first subset of rays. Accounting for variations in optical path length traversed within the sample can improve accuracy.

Apparatus and methods for optical detection of contamination are disclosed. In one arrangement, an excitation source (24) directs excitation radiation (26) into or onto an entity (22) to be tested. A first optical concentrator (28) is configured to receive radiation emitted due to fluorescence indicative of contamination in or on the entity (22). The emitted radiation (30) is received via an input surface (32). Concentrated radiation is output via an output surface (34). The first optical concentrator (28) comprises a first wavelength converting element that converts the received radiation to longer wavelength radiation prior to the output of the radiation via the output surface (34). A detection system (38) detects radiation output from the output surface of the first optical concentrator.

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 device and a method for analyzing a substance (5), comprising an excitation transmitting device in the form of a laser device (3) for generating at least one electromagnetic excitation beam (8), a measuring body (1) having a detection region (4), which is adjacent to a measuring surface (2) of the measuring body (1) and has a pressure-dependent or temperature-dependent specific electrical resistance and/or generates electrical, in particular piezoelectric, voltage signals in the event of pressure or temperature changes, and comprising a device for analyzing the substance on the basis of detected signals.

A system, device, and method for detecting and quantifying an analyte in a liquid include a vial having one or more pre-dosed reagents disposed in the vial. The vial is configured to hold a volume of a liquid including an analyte. The one or more pre-dosed reagents are dissolvable in the volume of the liquid to form a sample liquid solution comprising chromophores or fluorophores. The analyte and the one or more pre-dosed reagents react to yield the chromophores or fluorophores. The system further includes a detection device including a chamber configured to retain the vial, the detection device configured to quantify the analyte in the sample liquid solution. A device and method may perform the functions of the system.