A method for harmonizing the responses of a plurality of Raman analyzers includes steps of calibrating an intensity axis response of a spectrometer to a reference light source and measuring a laser wavelength of a laser using the spectrometer. The method also includes steps of measuring a fluorescence spectrum induced by the laser at the laser wavelength of a plurality of standard reference material samples using the spectrometer, measuring a temperature of each standard reference material sample while measuring the fluorescence spectrum, and correcting the fluorescence spectrum of each standard reference material sample based on the respective temperature. The method further includes steps of deploying each standard reference material sample in one of a plurality of field calibrator devices and calibrating the intensity axis of one of the Raman analyzers using one of the field calibrator devices and the corrected fluorescence spectrum of the respective standard reference material sample.

System and apparatus for robust, portable gas detection. Specifically, this disclosure describes apparatuses and systems for optical gas detection in a compact package using two optical pathways. There is a need for a very compact, low-power, gas detection system for gases such as CO2, NOx, water vapor, methane, etc. This disclosure provides an ultra-compact and highly stable and efficient optical measurement system based on principals of optical absorption spectroscopy using substantially collinear pathways.

A concentration measurement method is performed using a concentration measurement device comprising: a measurement cell for flowing a fluid to be measured; a light source for generating light incident on the measurement cell; a photodetector for detecting light emitted from the measurement cell; an arithmetic unit for calculating the absorbance and concentration of the fluid to be measured based on an output of the photodetector; and a temperature sensor for measuring the temperature of the fluid to be measured. The concentration measurement method includes: a step of flowing a gas whose molecular structure varies with the temperature as the fluid to be measured in the measurement cell; a step of making light of a wavelength absorbable by the fluid to be measured to be incident from the light source to the measurement cell; a step of measuring the intensity of light emitted from the measurement cell by the photodetector; and a step of calculating the concentration of the fluid to be measured based on the temperature and the output of the photodetector measured by the temperature sensor.

Provided is a sensor system having an improved SNR. The sensor system (1) includes: a sensor (gas sensor 10) including a light-emitting element (11) and a detecting element (light-receiving element 12) that detects a signal that is based on light emitted from the light-emitting element; and a computation device (20) that, by taking an interval in which the light-emitting element emits light as an ON interval and an interval in which the light-emitting element does not emit light as an OFF interval, uses the signal as detected in the ON interval and the signal as detected in a plurality of the OFF interval to compute one measurement value.

An imaging apparatus of the present disclosure includes: a liquid crystal panel configured to adjust light transmittance; a light emitting element configured to apply detection light; a first light receiving element configured to receive first detection light transmitted through the liquid crystal panel in the detection light, and to output a first output value related to a light amount of the first detection light; a second light receiving element configured to receive second detection light not transmitted through the liquid crystal panel in the detection light, and to output a second output value related to a light amount of the second detection light; a transmittance calculator configured to calculate a liquid crystal transmittance of the liquid crystal panel based on the first output value and the second output value; and an imaging element configured to image imaging light transmitted through the liquid crystal panel.

A Concentration measurement device 100 comprises: a measurement cell 4 having a flow path through which a gas flows, a light source 1 for generating incident light to the measurement cell, a photodetector 7 for detecting light emitted from the measurement cell, a pressure sensor 20 for detecting a pressure of the gas in the measurement cell, a temperature sensor 22 for detecting a temperature of the gas in the measurement cell, and an arithmetic circuit 8 for calculating a concentration of the gas based on an output P of the pressure sensor, an output T of the temperature sensor, an output I of the photodetector, and an extinction coefficient α, wherein the arithmetic circuit 8 is configured to calculate the concentration using the extinction coefficient α determined on the basis of the output of the temperature sensor 22.

A device for optical detection of analytes in a sample includes at least two optoelectronic components. The optoelectronic components include at least one optical detector configured to receive a photon and at least one optical emitter configured to emit a photon. The at least one optical emitter includes at least three optical emitters disposed in a flat, non-linear arrangement, and the at least one optical detector includes at least three optical detectors disposed in a flat, non-linear arrangement. The at least three optical emitters and the at least three optical detectors include at least three different wavelength characteristics.

System and apparatus for robust, portable gas detection. Specifically, this disclosure describes apparatuses and systems for optical gas detection in a compact package using two optical pathways. There is a need for a very compact, low-power, gas detection system for gases such as CO2, NOx, water vapor, methane, etc. This disclosure provides an ultra-compact and highly stable and efficient optical measurement system based on principals of optical absorption spectroscopy using substantially collinear pathways.

Quantitative colorimetric carbon dioxide detection and measurement systems are disclosed. The systems can include a gas conduit, a colorimetric indicator adapted to exhibit a color change in response to exposure to carbon dioxide gas, a temperature controller operatively coupled to the colorimetric indicator and configured to control the temperature of the colorimetric indicator, an electro-optical sensor assembly including a light source or sources adapted to transmit light to the colorimetric indicator, and a photodiode or photodiodes configured to detect light reflected from the colorimetric indicator and to generate a measurement signal, and a processor in communication with the electro-optical sensor assembly. The processor can be configured to receive the measurement signal generated by the electro-optical sensor assembly and to compute a concentration of carbon dioxide based on the measurement signal. Methods for using the systems are also disclosed including providing a breathing therapy to a patient or user.

A concentration measurement method is performed using a concentration measurement device comprising: a measurement cell for flowing a fluid to be measured; a light source for generating light incident on the measurement cell; a photodetector for detecting light emitted from the measurement cell; an arithmetic unit for calculating the absorbance and concentration of the fluid to be measured based on an output of the photodetector; and a temperature sensor for measuring the temperature of the fluid to be measured. The concentration measurement method includes: a step of flowing a gas whose molecular structure varies with the temperature as the fluid to be measured in the measurement cell; a step of making light of a wavelength absorbable by the fluid to be measured to be incident from the light source to the measurement cell; a step of measuring the intensity of light emitted from the measurement cell by the photodetector; and a step of calculating the concentration of the fluid to be measured based on the temperature and the output of the photodetector measured by the temperature sensor.