Methods and apparatus for detecting biological agents suspended in air in real time. A method includes emitting towards an air sample a beam of monochromatic polarized light whose wavelength corresponds to an absorption maximum of a biological molecule. The method further includes receiving, at different scattering angles, the scattered light beam after passing through the sample and determining that there are particles in the sample that contain the biological molecules of interest if the intensity of the scattered light has a substantially higher peak than the rest of the scattered light. The amount of the biological molecules is then estimated according to the amplitude of the peak. The size of the particles containing the biological molecules is also estimated as a function of the scattering angle where the peak was detected.

A lidar system for detection of a gas comprises an optical transceiver for transmitting and receiving optical radiation. A method of operating the system comprises performing spatially scanned sensing measurements of the gas across a system field of view, and analyzing the sensing measurements to determine the presence and location of excess of the gas in the system field of view. Based on the determined location, an adjusted system field of view is determined and spatially scanned sensing measurements of the gas are performed across the adjusted system field of view to obtain sensing measurements at higher spatial resolution.

Disclosed herein is an apparatus including a structure containing a multiphase fluid and having a transparent window. A collimated light source emits light through the transparent window structure at a wavelength at which a component of a desired phase of the multiphase fluid is absorptive. A photodetector is positioned such that the emitted light passes through the multiphase fluid in the structure and out through the transparent window structure to impinge upon the photodetector. The photodetector has an actual dynamic range for light detection. Processing circuitry adjusts a power of the collimated light source in a series of steps dependent upon a relationship between an output level of the photodetector and a threshold to cause measurement of the emitted light over an effective dynamic range greater than the actual dynamic range. Properties of the multiphase fluid are determined as a function of the measured emitted light.

An apparatus includes a pipe through which a multiphase fluid flows, with a transparent window structure formed in the pipe. A collimated light source emits light through the transparent window structure into the pipe having a wavelength at which a component of a desired phase of the multiphase fluid is absorptive. A photodetector is positioned such that the emitted light passes through the multiphase fluid in the pipe to impinge upon the photodetector. The photodetector has an actual dynamic range for collimated light detection. Processing circuitry is configured to continuously adjust a power of the collimated light source dependent upon an output level of the photodetector so as to cause measurement of the emitted light over an effective dynamic range greater than the actual dynamic range, and determine a property of the multiphase fluid as a function of the power of the collimated light source.

A new liquid flow cell assembly for light scattering measurements is disclosed which utilized a floating manifold system. The assembly operates with minimal stacked tolerances by aligning the cell to the windows within a manifold and independently aligning the cell to the read head directly. This configuration enables the ability to replace the flow cell or the flow cell/manifold assembly within a light scattering instrument without the need to realign the flow through elements with the light scattering illumination source while still maintaining reproducible, quality data. Some embodiments employ wide bore cells which enable the measurement of process analytic technology (PAT) including online monitoring of reactions.

The present invention relates in one aspect to a ballast water analysis system comprising fluorometer and light scattering meter. The fluorometer comprises a first light source arranged to illuminate a first ballast water sample for obtaining a first fluorescence measurement on a first ballast water sample. The light scattering meter comprises a second light source arranged to illuminate a second ballast water sample with a second light beam and first and second photodetectors arranged to receive light at respective angles relative to a direction of the second light beam. The second and third photodetectors are configured to receive scattered light resulting from interaction between light from the second light source and matter, such as viable or non-viable microorganisms and other particles, in the second ballast water sample.

This disclosure concerns methods and apparatus for interferometric spectroscopic measurements of particles with higher signal to noise ratio utilizing an infrared light beam that is split into two beams. At least one beam may be directed through a measurement volume containing a sample including a medium. The two beams may then be recombined and measured by a detector. The phase differential between the two beams may be selected to provide destructive interference when no particle is present in the measurement volume. A sample including medium with a particle is introduced to the measurement volume and the detected change resulting from at least one of resonant mid-infrared absorption, non-resonant mid-infrared absorption, and scattering by the particle may be used to determine a property of the particle. A wide range of properties of particles may be determined, wherein the particles may include living cells.

A turbidimeter (1) according to the present disclosure is for measuring turbidity of an object to be measured (S) and includes a light source (21) that irradiates an irradiation light (L1) towards the object to be measured (S), a light receiver (22) including a solid-state image sensor (222) that outputs a detection signal of light to be measured (L2) that includes transmitted light (L21) and scattered light (L22) based on the irradiation light (L1) irradiated towards the object to be measured (S), and a controller (31) that calculates a spatial distribution (D) of intensity of the light to be measured (L2) on a light-receiving surface (A) of the solid-state image sensor (222) based on a detection signal of the light to be measured (L2) and calculates the turbidity based on the calculated spatial distribution (D).

A method for continuously evaluating the effectiveness of debridement of a root canal of a tooth, the tooth having an open access cavity and an apex end, includes delivering a fluid to the open access cavity of the tooth, evacuating the fluid near the apex end of the tooth such that the fluid flushes most of the root canal before being evacuated, and continuously evaluating the evacuated fluid for at least one of a presence of debris, a concentration level of the debris, or a type of the debris. An apparatus for use in debriding a root canal of a tooth includes a microcannula or a macrocannula configured to evacuate a fluid in the root canal, and a sensing mechanism fluidically coupled to the microcannula or the macrocannula, the sensing mechanism configured to continuously sense debris in the evacuated fluid in real time.

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.