Abstract: A method of performing spectroscopic measurements provides an optical frequency comb, and directs the comb through or at a sample. The optical frequency comb is generated by gain switching a laser diode constructed from Gallium Nitride and related materials. Various techniques are described for manipulating the comb source to achieve desired benefits for spectroscopy.

Abstract: The disclosure provides an apparatus, a device, and methods for improving optical analysis of a thin layer of a sample between two plates, particularly for multiple wavelengths.

Abstract: The gas detection apparatus comprises a figure of all or a part of n ellipsoids. When a region inside the ellipsoid Ei and not including the ellipsoid Esi is defined as a region Ri, the ellipsoid Ei including a light source region of the light emitting part is defined as an ellipsoid Es, the ellipsoid Ei including a light receiving region of the light receiving part is defined as an ellipsoid Ed, the region Ri of the ellipsoid Es is defined as a region Rin, and the region Ri of the ellipsoid Ed is defined as a region Rout, 60% or more of the light source region is present in the region Rin and 60% or more of the light receiving region is present in the region Rout.

Abstract: Provided is a microparticle measuring apparatus including a plurality of light detection sections that detects, at different positions, optical information emitted from microparticles flowing through a flow channel. The microparticle measuring apparatus further includes a detection timing control section that controls a detection timing of each light detection section, on the basis of a trigger signal detected at a first reference channel provided in a first light detection section, and an optical signal detected at a second reference channel provided in a second light detection section that detects optical information emitted from the microparticles, at a position different from a position of the first light detection section.

Abstract: An imaging system, and method of its use, for viewing a sample surface at an inclined angle, preferably in functional combination with a sample investigating reflectometer, spectrophotometer, ellipsometer or polarimeter system; wherein the imaging system provides that a sample surface and multi-element imaging detector surface are oriented with respect to one another to meet the Scheimpflug condition, and wherein a telecentric lens system is simultaneously positioned between the sample surface and the input surface of the multi-element imaging detector such that an image of the sample surface produced by said multi-element imaging detector is both substantially in focus over the extent thereof, and such that substantially no keystone error is demonstrated in said image.

Abstract: Methods for determining a parameter of a particle in a flow stream (e.g., in a particle analyzer of a flow cytometer) from scattered light are described. Methods according to certain embodiments include irradiating a particle in a flow stream with a frequency-modulated beam of laser light modulated at a reference frequency, detecting scattered light from the particle with a photodetector, generating a frequency-encoded data signal from the detected scattered light, synchronizing the frequency-encoded data signal with the reference frequency and determining one or more parameters of the particle based on the synchronized frequency-encoded data signal. Systems and non-transitory computer readable storage medium with instructions for practicing the subject methods are also provided.

Abstract: A polarimeter and a method of analyzing and imaging microstructural material orientation of a sample are disclosed.

Abstract: The present invention relates to dust concentration measurement and to dust composition and particle size determination. Multimodal dust sensor is able to simultaneously determine the concentration, size and origin of dust particles in real time. Method of operation of a single measurement channel of the multimodal dust sensor comprises: collimating laser radiation; splitting the laser radiation into two beams: a first beam and a second beam; and focusing the first beam to form a probe volume, wherein a dust particle entering the probe volume: a) scatters the first beam, thereby providing a homodyne mode of operation, in which the second beam and the scattered first beam are combined; the combined radiation falls on the photodetector that registers the Doppler effect; and/or b) fluoresces, thereby providing a fluorescent mode of operation, in which the fluorescent light falls on the photodetector that registers the fluorescent light.

Abstract: A sample classification device including a carrier, a first detection module, and a sample pipeline is provided. The first detection module includes a first light-emitting device, a second light-emitting device, and a first optical sensing device. The first light emitting device is located on the carrier and used to emit light of a first wavelength. The second light emitting device is located on the carrier and used to emit light of a second wavelength. The first wavelength is different from the second wavelength. The first optical sensing device is located on the carrier and between the first light emitting device and the second light emitting device. The sample pipeline is located above the carrier and passes above the first optical sensing device.

Abstract: The present relates to a measurement device (1) for the detection and/or measurement of particles in a fluid, the measurement device comprising a fluid source (11) for producing a flow of fluid (111) along a fluid flow path, a first laser source (12) positioned for emitting a first laser beam (120) of laser light in a measurement volume of the fluid flow path for light scattering; a scattered light detecting means (13) for detecting a presence of a particle in the fluid flow path through detection and measurement of laser beam light scattered on different angles by said particle, wherein it further comprises a second laser source (14) positioned for emitting a second laser beam (140) of laser light in said measurement volume of the fluid flow path for Raman and fluorescence excitation; a Raman and fluorescence detecting means (15) for detecting a Raman scattering signal emitted by the fluid and a Fluorescence signal emitted by said particle upon excitation by said second laser beam (140).

Abstract: A device may receive, from a sensor device, cable distance data identifying cable distances along the fiber cable to vibrations experienced by the fiber cable from a vibration device. The device may receive location data identifying geographic coordinates associated with the vibrations, and may correlate the cable distance data and the location data to generate correlated data. The device may receive, from the sensor device, data identifying a cable distance along the fiber cable to an alarm condition associated with the fiber cable, and may determine geographic coordinates associated with the alarm condition based on the correlated data and the data identifying the cable distance along the fiber cable to the alarm condition. The device may perform actions based on the geographic coordinates associated with the alarm condition.

Abstract: Device for improving an optical detecting smoke apparatus and implementing thereof. Apparatus and methods for detecting the presence of smoke in a small, long-lasting smoke detector are disclosed. Specifically, the present disclosure shows how to build one or more optimized blocking members in a smoke detector to augment signal to noise ratio. This is performed while keeping the reflections from the housing structure to a very low value while satisfying all the other peripheral needs of fast response to smoke and preventing ambient light. This allows very small measurements of light scattering of the smoke particles to be reliable in a device resistant to the negative effects of dust. In particular, geometrical optical elements, e.g., cap and optical defection elements, are disclosed.

Abstract: An apparatus for carrying out Raman spectroscopy on a sample includes a light source for providing a beam of excitation radiation, and an optical system including a spectrograph. The spectrograph includes a grating that divides a beam of scattered light into a spectrum of spatially separated wavelength components and to direct a portion of the spectrum to a detector. The spectrograph includes: 1) a first lens system for focusing the portion of the spectrum onto the detector and 2) a second lens system-configured to provide a focal plane with focal point in the optical path for focusing the beam of excitation radiation and/or the beam of scattered radiation at the focal point. The apparatus including a reference sample arranged in the focal plane, in particular at the focal point, for obtaining a reference spectrum from the reference sample.

Abstract: Aspects of the present disclosure include methods for adjusting sensitivity of a photodiode in a light detection system. Methods according to certain embodiments include determining a background data signal from a photodetector at a plurality of detector gains, irradiating the photodetector with a light source at a plurality of different light intensities, generating data signals from the photodetector for the plurality of light intensities at each detector gain and adjusting the photodetector to the detector gain that corresponds to the lowest light irradiation intensity that generates a data signal resolvable from the background data signal. Systems (e.g., particle analyzers) having a light source and a light detection system that includes a photodetector for practicing the subject methods are also described. Non-transitory computer readable storage medium are also provided.

Abstract: The present application discloses a nanoparticle recognition device and method based on detection of scattered light with electric dipole rotation. According to the scattering model of nanoparticles, the in situ detection of particle morphology in an optical trap is realized by the methods of particle suspension control and scattered light detection and separation. Specifically, two linearly polarized laser beams are used, wherein the first laser beam suspends nanoparticles and rotates nanoparticles by adjusting the polarization direction; the polarization direction of the second linearly polarized light is unchanged, and scattered light in a specific dipole direction is excited; the change of the polarizability of the nanoparticles is deduced by monitoring the change of the light intensity of the scattered light excited by the second laser beam at the fixed position, so that particle morphology recognition is realized.

Abstract: Various sensors, including particulate matter sensors, are described. One particulate matter sensor includes a self-mixing interferometry sensor and a set of one or more optical elements. The set of one or more optical elements is positioned to receive an optical emission of the self-mixing interferometry sensor, split the optical emission into multiple beams, and direct each beam of the multiple beams in a different direction. The self-mixing interferometry sensor is configured to generate particle speed information for particles passing through respective measurement regions of the multiple beams.

Abstract: Apparatus and methods for determining particle size, and optionally, the complex index of refraction for particle suspended in a gas or liquid are provided. The particle to be analyzed is caused to travel through a laser beam having a modified Gaussian profile. The particle causes light from the laser beam to scatter. The scattered light is measured by one or more photodetectors disposed at a particular scattering angle relative to the center of the laser beam. The apparatus and methods can be used in sensors configured to monitor air quality in enclosed environments, such as on-board aircraft and within buildings, and/or detect environmental contaminants.

Abstract: A particle detection device includes: a first light source to emit first irradiation light; a first light-collection member; a second light-collection member facing the first reflection surface; a second light source to emit second irradiation light; and a first light-reception element. When the first light source emits the first irradiation light, the first light-reception element detects, as the first incident light, scattered light generated when a particle existing at a detection position in a target space is irradiated with the first irradiation light. When the second light source emits the second irradiation light, the first light-reception element detects, as the first incident light, a light ray of the second irradiation light that is reflected by the first reflection surface and a light ray of the second irradiation light that is reflected by both the first reflection surface and the second reflection surface.

Abstract: A system comprises a particle sensor unit in communication with a processor. The sensor unit comprises a source that transmits light into an interrogation region; receive optics that collect scattered light from particles in the interrogation region; and an optical detector that receives the collected light from the receive optics. The detector comprises a sample area including one or more sampling pixels, and an edge region including one or more edge pixels. The processor analyzes intensity data from the detector by a method comprising: combining all intensity data from the sampling pixels; adding the combined intensity data to a data set; determining whether to accept overlap intensity data that corresponds to an overlap between the sampling pixels and the edge pixels; adding the overlap intensity data to the data set if accepted; discarding the overlap intensity data if not accepted; and discarding all non-overlapping intensity data from the edge pixels.

Abstract: An optical beam controller includes: an optical multiple-beam generator generating a plurality of wavelength-swept optical beams; and an optical frequency difference setter setting an optical frequency difference in any combination of the plurality of optical beams in such a way as to be larger than a band of a photodetector that receives an optical beam.