The present invention enables an analysis device that utilizes light absorption to measure concentrations of target components by means of a simple calculation, and without any complex spectrum calculation processing being required, and analyzes target components that are contained in a sample, and is provided with a light source that emits modulated light whose wavelength is modulated relative to a central wavelength using a predetermined modulation frequency, a photodetector that detects an intensity of sample light obtained when the modulated light is transmitted through the sample, a correlation value calculation unit that calculates correlation values between intensity-related signals that are related to the intensity of the sample light, and predetermined feature signals, and a concentration calculation unit that calculates concentrations of the target components using the correlation values obtained by the correlation value calculation unit.

The present invention discloses a method of infrared spectrometric measurement of tunnel gas employing a gas measurement system including a gas collection unit, a gas analysis unit and a positioning indication unit for measuring the gas in the tunnel. The method performs sequential steps of installing the gas measurement system, starting the positioning indication unit for positioning one of the detection regions in the tunnel space, sampling the gas in the detection region through the gas collection unit, analyzing the gas by the gas analysis unit, generating a gas analysis result, and determining whether all of the detection regions are completed. With the newly designed gas collection unit in collocation with the gas analysis unit and the positioning indication unit, the method of the present invention does not only fast install the whole gas measurement system, but also well understands all preliminary information related to the harmful gas in the tunnel like sort and concentration, thereby instantly taking correct measures.

An analyzer analyzes a measurement sample on the basis of spectrum data obtained by irradiating light to the measurement sample. The analyzer includes a main analysis part, a correlation data storage part and a concentration calculation part. The main analysis part calculates a concentration of a predetermined hydrocarbon component contained in the measurement sample on the basis of the spectrum data of the measurement sample. The correlation data storage part stores therein a plurality of correlation data each indicating a correlation between a concentration of the predetermined hydrocarbon component or the spectrum data and a THC concentration. The concentration calculation part selects at least one correlation data from among a plurality of correlation data stored in the correlation data storage part according to the concentration of the predetermined hydrocarbon component, and calculates a concentration of the total hydrocarbon components in the measurement sample by using correlation data thus selected.

A device for measuring oxygen saturation includes circuitry configured to measure a first diode voltage at a light emitting diode while applying a first current through the light emitting diode, measure a second diode voltage at the light emitting diode while applying a second current through the light emitting diode, and measure a third diode voltage at a light emitting diode while applying a third current through the light emitting diode. The circuitry is further configured to determine a series resistance based on the first diode voltage, the second diode voltage, and the third diode voltage and determine an intensity of a received photonic signal corresponding to an output photonic signal output using the light emitting diode. The circuitry is further configured to determine an oxygen saturation level based on the intensity of the received photonic signal and the series resistance.

A cavity enhanced absorption spectroscopy (CEAS) system is provided that utilizes collimators the incorporate gradient index (GRIN) lenses in lieu of conventional spherical or aspheric refractive lenses. The use of smaller diameter GRIN lenses facilitates a reduced initial beam size entering the sample cavity, which reduces self-interference noise and increases a signal to noise ratio of the measurements. Further, a reduced size and mass of the GRIN lens can reduce a size of the mounting hardware utilized to mount the optical components, which enables more laser beams to be coupled to a single gas cell compared to a similar gas cell integrated with conventional refractive collimators. A larger number of lasers enables more gas peaks to be measured substantially simultaneously using the CEAS system.

A method of detecting natural gas releases that includes the step of traversing a target area with a gas-filter correlation radiometer having a field of view oriented towards the target area. The gas-filter correlation radiometer receives reflected radiation in a passband from the target area and produces gas-filter correlation radiometer signals from the received reflected radiation. A surface reflectivity spectral profile of the target area is determined. The presence of methane in the target area is then determined based upon the received reflected radiation and the surface reflectivity spectral profile of the target area.

The present invention enables an analysis device that utilizes light absorption to measure concentrations of target components by means of a simple calculation, and without any complex spectrum calculation processing being required, and analyzes target components that are contained in a sample, and is provided with a light source that emits modulated light whose wavelength is modulated relative to a central wavelength using a predetermined modulation frequency, a photodetector that detects an intensity of sample light obtained when the modulated light is transmitted through the sample, a correlation value calculation unit that calculates correlation values between intensity-related signals that are related to the intensity of the sample light, and predetermined feature signals, and a concentration calculation unit that calculates concentrations of the target components using the correlation values obtained by the correlation value calculation unit.

There is provided a substance detecting device emits first invisible light to the inside and the outside of a detection region of a substance, changes an emitting direction of the first invisible light inside and outside the detection region, receives third invisible light which is passing light of the first invisible light through the reference cell in which a detection target substance is stored, outside of the detection region, and adjusts a temperature of the first invisible light and controls the wavelength of the first invisible light based on the wavelength characteristics of the third invisible light.

A method of detecting natural gas releases that includes the step of traversing a target area with a gas-filter correlation radiometer having a field of view oriented towards the target area. The gas-filter correlation radiometer receives reflected radiation in a passband from the target area and produces gas-filter correlation radiometer signals from the received reflected radiation. A surface reflectivity spectral profile of the target area is determined. The presence of methane in the target area is then determined based upon the received reflected radiation and the surface reflectivity spectral profile of the target area.

A gas concentration-length quantification method, including: acquiring a first image including a gas plume with a camera; identifying and segmenting pixels corresponding to the gas plume in the first image; generating a background image corresponding to the first image using an image inpainting algorithm with the first image and positional information of the segmented pixels corresponding to the gas plume as inputs; calculating a gas concentration-length for each pixel corresponding to the gas plume in the first image, based on the first image and the background image data; and triggering an alert when the gas concentration-length for at least one pixel exceeds a threshold level.