An optical analysis of saliva or a fluid-saliva mix obtained during or after an oral care action is performed in order to check whether the saliva or fluid-saliva mix contains blood, which allows for determining whether or not a person may suffer from gingivitis or another condition affecting gum health. In particular, light received from a representative sample (23) containing saliva is detected and analyzed. The analysis involves determination of measurement values of light received by a light-receiving unit (25) for one or more main wavelengths of the light and one or more auxiliary wavelengths of the light. Advantageously, the main wavelength(s) is/are associated with high hemoglobin absorption and the auxiliary wavelength(s) is/are associated with low hemoglobin absorption. A measurement value at an auxiliary wavelength is used for correcting a measurement value at as main wavelength for background influences.

An optical coherence tomography (OCT) apparatus includes a light source unit to generate light, a coupler unit to generate coupled light using reference light and measurement light generated by splitting the light, split the coupled light into n coupled and split lights and irradiate the n coupled and split lights, wherein n is a natural number greater than or equal to 2, a detection unit to irradiate the incident n coupled and split lights to n spectroscopes respectively and sequentially scan each light separated from each of the spectroscopes by wavelength range, and an image generation unit to generate a 2-dimensional single image using a result of the scanning by the detection unit. Accordingly, it is possible to improve the OCT image acquisition rate by distributing the scan time for a plurality of split lights using a plurality of array detectors.

There is provided a gas sensing device for sensing a certain gas that is associated with a certain spectral band, the gas sensing device may include a passive gas sensor that is configured to generate passive gas sensor detection signals that are responsive to the certain spectral band; a passive dummy sensor that is configured to generate passive dummy sensor detection signals that are indifferent to the certain spectral hand; and at least one circuit that is configured to detect a presence or absence of the certain gas within a certain volume that is located within the fields of view of the passive gas sensor and the passive dummy sensor based on a comparison between the passive gas sensor detection signals and the passive dummy sensor detection signals.

A gas sensor device (100) is configured to measure a predetermined gas of interest and comprises an enclosure (101) comprising a semiconductor substrate (102) and defining a first cavity (124), an optically transmissive second closed cavity (126) and a third cavity (128). The second cavity (126) is interposed between the first and third cavities (124, 128). The first cavity (124) comprises an inlet port (130) for receiving a gas under test, an outlet port (132) for venting the gas under test. The first cavity (124) also comprises an optical source (112) and a measurement sensor (114). The second cavity (126) is configured as a gaseous filter comprising a volume of the gas of interest sealingly disposed in the second cavity (126), and the third cavity (128) comprises a reference measurement sensor (116) disposed therein.

A gas analyzer for measuring a respiratory gas component includes an emitter that emits two different wavelengths of infrared (IR) radiation in to a measurement chamber containing a respiratory gas, wherein the two different wavelengths include a first IR wavelength and a second IR wavelength. The gas analyzer further includes a first IR detector, a second IR detector, and a beam splitter. The beam splitter is configured to receive the two different wavelengths of radiation emitted by the emitter and to split the two wavelengths of radiation so as to reflect the first IR wavelength to the first IR detector and reflect the second IR wavelength to the second IR detector.

A sensor apparatus having a sensor unit. The sensor unit including pixel assemblages on a substrate upper side of a substrate located on a lower side of the sensor unit; a cap, on the substrate upper side, which covers the pixel assemblages, a cavity being formed between the substrate upper side and the cap; a plurality of filters that are transparent to wavelength regions that differ from one another, exactly one pixel assemblage being associated with each filter; and the filters being on the cap so that the infrared radiation propagated through an absorption gap of the sensor apparatus and the upper side of the sensor unit is detectable, through the respective filter, by the pixel assemblage associated with the respective filter; and a coating made of a light-absorbing and/or light-reflecting material being configured at least locally on a part of the cap which is not covered by the filters.

With the present invention, it is possible to provide an inspection tool capable of easily inspecting whether or not light which inactivates a virus or the like has been radiated and easily inspecting whether or not light which is harmful to the human body has been radiated. The inspection tool of the present invention includes a first display portion and a second display portion, in which the first display portion is a display portion which indicates a visual change before and after irradiation of the inspection tool with light having at least any of wavelengths in a wavelength range of 200 to 280 nm, and the second display portion is a display portion which does not indicate a visual change before and after irradiation of the inspection tool with light in a wavelength range of 200 to 230 nm, but indicates a visual change before and after irradiation of the inspection tool with light having at least any of wavelengths in a wavelength range of more than 230 nm and 280 nm or less.

Provided is a residual toxicant detection system and a residual toxicant detection method, the residual toxicant detection method including: allowing an aqueous solution containing a residual toxicant to flow into a detection portion including a cavity; providing at a side of the cavity a light containing a specific wavelength range to react with the residual toxicant; receiving the light that passes through the cavity on another side of the cavity, thereby generating a sensing signal; and calculating an amount of change in absorbance of the aqueous solution according to the sensing signal, wherein when the amount of change in absorbance is less than a threshold value, a detection count is accumulated, and when the accumulated detection count is greater than a predetermined value, a detection result is generated. Therefore, whether or not the residual toxicant on the object is cleaned can be determined easily and accurately.

A methodfor measuring an amount of a gaseous species present in a gascomprises placing the gas between a light source and a measurement photodetector. The light source is able to emit an incident light wave that propagates through the gas to the measurement photodetector. The gas is illuminated with the light source. A measurement intensity, of the light wave transmitted by the gas, is measured with the measurement photodetector. An intensity of a reference light wave, emitted by the light source in a reference spectral band, is measured with a reference photodetector. The illumination and measuring are performed at multiple measurement times, at each of which the gas's absorption of the incident light wave is estimated and an amount of the gaseous species is estimated on the basis of the estimated absorption. Estimating the absorption comprises applying a correction function, that varies over time, to the reference intensity.

In order to make it possible to conduct a zero calibration even though an interference gas exists in a measurement area of a detector, a light absorbance analysis apparatus includes a detector that detects an intensity of light that transmits a gas, a total pressure sensor that measures a total pressure of the gas, an absorbance calculating part that calculates an absorbance based on an output value of the detector and a previously set zero reference value, a partial pressureabsorbance relation storing part that stores a partial pressureabsorbance relational data that indicates a relationship between a partial pressure of an interference gas that exists in a measurement area of the detector and an absorbance calculated by the absorbance calculating part, and a partial pressure calculating part that calculates an interference gas partial pressure as a partial pressure of the interference gas.