A measuring apparatus is provided with: an irradiator configured to irradiate fluid with light; a first light receiver configured to receive a forward scatter component of scattered light scattered by the fluid; a second light receiver configured to receive a backscatter component of the scattered light; a third light receiver configured to receive a side scatter component of the scattered light; and an outputting device configured to output fluid information about the fluid, which is obtained on the basis of light receiving signals of the first light receiver, the second light receiver, and the third light receiver. According to this measuring apparatus, it is possible to output accurate fluid information because of the use of the forward scatter component, the backscatter component, and the side scatter component of the scattered light.

A method for a wearable device to determine a biological parameter of a tissue of a person. To apply an emitting of a first and a second wavelength of light towards the tissue. To collect and sense a first and a second set of frequency bands from the signals received back from the first and the second wavelengths, respectively. The first set of frequency bands represents a first signal which corresponds to a combination of the biological parameter and an extraneous noise. The second set of frequency bands represents a second signal mainly comprising the extraneous noise. To subtract the first set of frequency bands from the second set of frequency bands in the frequency domain to obtain a third set of frequency bands. The third set of frequency bands represents a third signal corresponding to the biological parameter.

A method for characterizing particle objects comprises generating a radiation beam, illuminating with the radiation beam an observation region transited by a particle object, collecting an interference image determined by an interference between a transmitted fraction and a part of the scattered fraction of the radiation beam that propagates around the direction of the optical axis, collecting a part of the scattered fraction that propagates at the scattering angle, and measuring at least one scattered radiation intensity value determined by the part of the scattered fraction, calculating, from the interference image, a pair of independent quantities that define the complex field of the first part of the scattered fraction, calculating, starting from the pair of independent quantities, a theoretical value of scattered radiation intensity, and comparing the measured value with the theoretical scattered radiation intensity value.

A flow cell system for an optical fluid analysis comprises a disposable flow cell having at least one flow chamber comprising a fluid pathway, and at least one pair of opposed light transmitting windows along the fluid pathway, an external flow cell holder for holding the flow cell, at least one light source, and an external detection device couplable with at least one of the flow cell holder and the flow cell for bringing the external detection device in optical communication with the flow cell, the device having at least one optical detection unit. The external detection device is configured to conduct optical measurements of the fluid that flows in the flow cell through at least one pair of windows from externally under illumination by the at least one light source.

According to an aspect of the present inventive concept there is provided a light excitation and collection device for a micro-fluidic system, comprising: a light source configured to generate excitation light; a plurality of excitation waveguides, each associated with a flow channel of the micro-fluidic system; wherein each excitation waveguide is configured to receive and redirect the excitation light towards the flow channel, such that the excitation light is elastically scattered by a sample in the flow channel forming forward and side scattered light; and wherein the light excitation and collection device further comprises: at least one forward scattered light collection point; and at least one side scattered light collection point; and wherein the forward scattered light collected for all excitation waveguides is detected by a first plurality of light sensitive areas and the side scattered light collected for all excitation waveguides is detected by a second plurality of light sensitive areas, the first and the second pluralities of light sensitive areas form different groups of light sensitive areas.

A method for measuring concentrations of blood cell components is provided. The method comprises: obtaining a blood sample from a subject, the blood sample comprising at least one of red blood cells (RBCs), white blood cells (WBCs), and platelets (PLTs); mixing the blood sample with a non-lysing aqueous solution to form a sample mixture comprising a predetermined tonicity; passing the sample mixture through a flow cell; emitting light towards the flow cell; measuring at least one of an amount of light absorbed by the RBCs to obtain an RBC absorption value, an amount of light scattered by WBCs to obtain a WBC scatter value, and an amount of light scattered by PLTs to obtain a PLT scatter value; and determining a concentration of at least one of the RBCs, WBCs, and PLTs present in the sample mixture.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, that generate from a first pair and a second pair of images of livestock that are within an enclosure and that are taken at different times using a stereoscopic camera, at least two distance distributions of the aquatic livestock within the enclosure. The distance distributions can be used to determine a measure associated with an optical property of the water within the enclosure. A signal associated with the measure can be provided.

A fluid measuring apparatus is provided with: an irradiating device configured to irradiate a fluid with light; a light receiving device configured to receive light scattered by the fluid; a detecting device configured to detect a backflow of the fluid on the basis of a received light signal of the light receiving device; and a calculating device configured to calculate estimated concentration information indicating a concentration of the fluid, on the basis of a detection result of the detecting device and the received light signal of the light receiving device. By this, even if the backflow temporarily occurs in the fluid, the fluid concentration can be accurately measured.

Techniques for quantitative colorimetric liquid analysis with color and turbidity correction are provided. In one aspect, an optical detector includes: a vessel for containing a liquid sample; a light source on a first side of the vessel; a first sensor on a second side of the vessel opposite the first side and along a light path of the light source; and a second sensor on a third side of the vessel at an angle θ with respect to the light path. A method for quantitative measurement of an analyte is also provided, as is a method for color and turbidity analysis.

Nephelometric measuring devices are described. The nephelometric measuring devices can be configured such that an amount of scattered light having different pathlengths impingent upon one or more scattered-light detectors from a beam propagating through a suspension can result in substantially equivalent sensitivity and in correlation between the scattered-light detectors' response and a turbidity value of the suspension. The response of the scattered-light detector(s) receiving scattered light at a nephelometric angle of 85-110° from a beam of light propagating through the suspension can be in accordance to an equation selected from a group of non-linear equations where: x/y=a.sub.nx.sup.n+a.sub.n−1x.sup.n−1+ . . . +a.sub.2x.sup.2+a.sub.1x+a.sub.0; where “n” is an integer greater than 0; “x” is equal to the turbidity value of the suspension; “y” is equal to the response of the scattered-light detector; and “a.sub.n” are calibration coefficients. The maximum response of the scattered-light detector occurs at a turbidity value dependent upon the effective scattered-light pathlength.