A maturity determination device includes an image capturing device to capture a image including a plurality of first and second pixels; and a signal processing circuit configured to find an area size ratio of an intensity distribution of light of a first wavelength band on the basis of a predetermined reference value based on pixel values obtained from the plurality of first and second pixels, and to generate maturity determination information in accordance with the area size ratio. The first pixel includes a first light transmission filter, and the second pixel includes a second light transmission filter. The intensity of the light of the first wavelength band reflected by the fruits and vegetables varies in accordance with the maturity level, and the intensity of the light of the second wavelength band reflected by the fruits and vegetables is substantially the same regardless of the maturity level.

An apparatus includes an integrated sensor module for detection of chemical substances. The sensor module includes a UV radiation source operable to emit UV radiation onto a sample. The sensor module also includes a sensor including dedicated channels disposed so as receive UV radiation reflected by the sample. Each of the channels is selectively sensitive to a different respective portion of the UV spectrum; collectively, the channels cover at least part of the UV spectrum sufficient for reconstruction of a spectral curve of the sample. An electronic control unit can be used to identify a composition of the sample based on signals from the channels.

One example provides a system for reading birefringent data. The system comprises one or more light sources, a first polarization state generator positioned to generate first polarized light from light of a first wavelength band output by the one or more light sources, a second polarization state generator positioned to generate second polarized light from light of a second wavelength band output by the one or light sources, an image sensor configured to acquire an image of the sample region via the first polarized light and the second polarized light, a polarization state analyzer disposed between the sample region and the image sensor, a first bandpass filter configured to pass light of the first wavelength band onto the image sensor, and a second bandpass filter configured to pass light of the second wavelength band onto the image sensor.

A non-dispersive multi-channel radiation sensor assembly includes a beamsplitter assembly, a first band-pass filter, which has a predefined first bandwidth and has a transmission maximum at a predefined first useful-signal wavelength, a first measurement-radiation useful-signal sensor, which is arranged downstream of the first band-pass filter in the beam path, a second band-pass filter, which has a transmission maximum at a predefined first reference-signal wavelength, a first measurement-radiation reference-signal sensor, which is arranged downstream of the second band-pass filter in the beam path. The beamsplitter assembly has a first irradiation region and a second irradiation region, in which irradiation regions the beamsplitter assembly is irradiated with measurement radiation. The irradiation regions are optically designed in such a way that the beamsplitter assembly deflects, in the first irradiation region, a first part of the measurement radiation onto the first band-pass filter and a second part of the measurement radiation onto the second band-pass filter.

A gas sensor (2) distinguishes between a target gas and a contaminant and includes a light source (8), a measurement volume (4), a detector (22), and an adaptable filter system (20) with a first optical filter and a second optical filter. The filter system switches between a first composite state, with both filters in a reference state, a second composite state, with the first filter in a first reference state and the second filter in a second measurement state, a third composite state with the first filter in a first measurement state and the second filter in a second reference state, and a fourth composite state, with both filters in a measurement state. The gas sensor detects a target gas and makes a determination as to a presence of the contaminant by comparing the respective detector signals, generated during at least three of the composite states, with each other.

One example provides a system for reading birefringent data. The system comprises one or more light sources, a first polarization state generator positioned to generate first polarized light from light of a first wavelength band output by the one or more light sources, a second polarization state generator positioned to generate second polarized light from light of a second wavelength band output by the one or light sources, an image sensor configured to acquire an image of the sample region via the first polarized light and the second polarized light, a polarization state analyzer disposed between the sample region and the image sensor, a first bandpass filter configured to pass light of the first wavelength band onto the image sensor, and a second bandpass filter configured to pass light of the second wavelength band onto the image sensor.

One example provides a system for reading birefringent data. The system comprises one or more light sources, a first polarization state generator positioned to generate first polarized light from light of a first wavelength band output by the one or more light sources, a second polarization state generator positioned to generate second polarized light from light of a second wavelength band output by the one or light sources, an image sensor configured to acquire an image of the sample region via the first polarized light and the second polarized light, a polarization state analyzer disposed between the sample region and the image sensor, a first bandpass filter configured to pass light of the first wavelength band onto the image sensor, and a second bandpass filter configured to pass light of the second wavelength band onto the image sensor.

A method—for measuring an amount of a gaseous species present in a gas—comprises 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.

A method for measuring an amount of a gas species able to absorb light in an absorption spectral band includes placing a gas between a measurement photodetector and a light source able to emit an incident light wave propagating through the gas to the photodetector. Electrical supply current passes through the light source to bring it to a temperature value. At multiple times: the light source illuminates the gas; the measurement photodetector measures a “measurement” intensity of a light wave transmitted by the gas in a measurement spectral band; and a reference photodetector measures a “reference” intensity of a reference light wave emitted by the light source in a reference spectral band. At each measurement time, a correction function representative of a variation in the incident light wave's intensity in the measurement band relative to in the reference spectral band is taken into account based on the measured reference intensity.

One example provides a system for reading birefringent data. The system comprises one or more light sources, a first polarization state generator positioned to generate first polarized light from light of a first wavelength band output by the one or more light sources, a second polarization state generator positioned to generate second polarized light from light of a second wavelength band output by the one or light sources, an image sensor configured to acquire an image of the sample region via the first polarized light and the second polarized light, a polarization state analyzer disposed between the sample region and the image sensor, a first bandpass filter configured to pass light of the first wavelength band onto the image sensor, and a second bandpass filter configured to pass light of the second wavelength band onto the image sensor.