113 results about "Elastic scattering" patented technology

Enhanced methods, apparatuses and systems are disclosed for the real-time detection and classification of biological and non-biological particles by substantially simultaneously measuring a single particle's characteristics in terms of size and density, elastic scattering properties, and absorption and fluorescence.

An apparatus for image elastic scattering spectroscopy is disclosed that is comprised of a light source for generating polarized light. Means are provided to convey the polarized light to a target. A collector receives light reflected from the target. A detector is responsive to the collector for generating images at both parallel and perpendicular polarizations for each of a plurality of wavelengths. A range finder detects a distance to the target. Control electronics control the image generation and the range finder. The apparatus may be configured to image areas on the surface of the body or configured so as to be inserted into various body cavities. Typically, the apparatus will be used in conjunction with an analyzer for analyzing the images for evidence of abnormal cells. Methods of gathering data and of screening for abnormal cells are also disclosed.

A compact and robust imaging Raman spectrograph has a collimating input lens assembly, a spectral filter assembly, a transmission diffraction grating, a focusing lens assembly, and a light detector. The spectral filter assembly is located between the two lenses and comprises a notch or long-pass filter optical interference filter, a plurality of optical channel plates for limiting the optical acceptance angle of the light passing the optical interference filter, and a transmission diffraction grating, all mounted in a single assembly. The spectral filter assembly permits a very high degree of elastically scattered light rejection and excellent stray-light reduction and management, while permitting a high level of optical throughput to maximize the signal of the weakly scattered Raman signal.

A neutron elastic scattering detector device for non-invasively detecting the presence of at least one predetermined element of an object of interest. The detector device comprises a neutron source that simultaneously outputs, at a creation time, a neutron in a first direction and an associated baseline particle in a second direction. The first direction is opposite of the second direction. The neutron can impinge upon the predetermined element of the object of interest and scatter therefrom in a third direction. A baseline particle detector system detects the baseline particle and outputs a baseline signal characteristic thereof. A neutron detector system detects the neutron and outputs a scattering signal in characteristic thereof. The processing unit analyzes the baseline signal and the scattering signal to determine the presence of the predetermined element.

To enable measurement of an elastically scattered electron image, a characteristic-X-ray-based element image and an electron-beam-energy-spectroscopy-based element image with a high S/N and high spatial resolution in an electronic microscope having a function to produce an element image. Measurement of a characteristic X-ray signal and electron beam energy loss spectra or measurement of a plurality of energy filter signals including a core loss of an observed element is performed simultaneously and continuously with detection of elastically scattered electrons transmitted through a specimen to be analyzed, and element images based on characteristic X-rays and electron beam energy spectroscopy are added up while correcting a positional misalignment with respect to elastically scattered electron images continuously observed (see FIG. 1).

The invention discloses a vibration-rotational Raman-Mie scattering multi-wavelength laser radar system and a working method thereof. The system comprises a first system and a second system, wherein the first system works in an ultraviolet wave segment, the second system works in a visible infrared wave segment, and the first system and the second system both comprise laser emission units, optical receiving units, signal detection and data collecting units and control units. The laser emission units are used for emitting lasers to air, the optical receiving units are used for receiving back scattering echo signals of the air on the lasers emitted by the laser emission units, and conduct rotational Raman, vibration Raman and elastic scattering light splitting on the back scattering echo signals, the signal detection and data collecting units are used for obtaining parameter information of air temperature, water vapor, aerosol and cloud from the back scattering echo signals after light splitting, and the control units are used for controlling the laser emission units, the optical receiving units and the signal detection and data collecting units to run. The vibration-rotational Raman-Mie scattering multi-wavelength laser radar system and the working method of the system can achieve all-weather air comprehensive continuous automatic observation.

A flow cytometer assembly includes a fluid controller configured to form a hydrodynamically focused flow stream including an outer sheath fluid and an inner core fluid. A coherent light source is configured to illuminate a particle in the inner core fluid. A detector is configured to detect a spatially coherent distribution of elastically scattered light from the particle excited by the coherent light source. An analyzing module configured to extract a three-dimensional morphology parameter of the particle from a spatially coherent distribution of the elastically scattered light.

The invention discloses a laser radar device for detecting the atmospheric temperature based on a vibration-rotation Raman spectrum. After laser is emitted from a laser device, the light beam can be amplified and the diffusion angle can be compressed by using a beam expander, and finally the light beam is emitted to the atmosphere through a pointing mirror; atmospheric back scattering light is collected by using a telescope, subsequently passes through an aperture diaphragm, and is finally led into a subsequent optical system through an optical fiber; the outgoing light of the optical fiber is converted into collimated parallel light by using a collimating lens, and is subsequently divided into two paths of signals by using a beam splitter, one path of the signals passes through a low-order signal light filtering piece, and the other path of the signals passes through a high-order signal light filtering piece; the two paths of the signal light is converted into electric signals through a photomultiplier I and a photomultiplier II, and is subsequently acquired and stored by using an acquirer. The strength of a vibration-rotation Raman spectral line is related to the atmospheric temperature, and different from a pure rotation Raman spectral line which is in an interval of 1-3nm from an elastic scattered ray, a vibration Raman spectral line is in an interval of 70nm from the elastic scattered ray, so that interference of an elastic scattering signal can be effectively avoided by adopting the vibration Raman spectral line.

The invention provides a vibration Raman laser radar scattering optical processing system based on a narrow bandpass filter and a reflex prism, and a processing method thereof. Aiming at two problems of a wide dynamic range of laser radar signal intensity and strong noise signal relative to a Raman scattering signal, the method and the system divide back scattering light into a high channel and a low channel for detecting and sufficiently utilize the narrow bandpass filter to improve the accuracy of temperature measurement and enlarge the range of the temperature measurement. An upper noise signal is relative weak, and can be fed into a photoelectric detection system for detecting through the narrow bandpass filter for once; and a lower noise signal is strong, the back scattering light of atmosphere passes through the same optical filter for twice by special optical technology, and spectrum of total transmittance is equivalent to squared spectrum of single transmittance so as to furthest suppress photonoise. After elastic scattering and background light of emission wavelength are compressed, under the condition of a multiplier tube is unsaturated, the echo intensity of the Raman scattering signal can be improved by increasing single pulse energy of emission laser, thereby achieving the aims of improving the accuracy of the temperature measurement and enlarging the range of the temperature measurement.

A method and apparatus for enabling chemical identification of individual particles, cells of molecules by obtaining a Raman spectrum of a particle, cell or molecule as it flows past a sensing point in a flow cytometer. The particles, which may be cells or molecules, are associated with a suitable noble metal colloid or colloidal aggregate. Cellular particles may be associated with gold or silver colloidal particles by ultra-sonic sonification while in a sample preparation reservoir containing the gold or silver colloidal suspension. The colloid associated particles are then hydrodynamically focused into a single file by a fluid control module. The surface-enhance Raman Spectrum of individual particles are obtained by illuminating the particle with a laser as the particle flows past a sensing point and gathering the light that is non-elastically scattered (Raman scattered) by the particle. The surface-enhanced Raman spectrum is then analyzed to identify the particle.

The invention discloses a backward elastic scattering spectral measurement analysis system and method for online detection of size distribution of small particles in a suspension. A linear array fiber probe and an off-axis parabolic reflector are used to construct a multi-angle spectral measurement system, and a spectral analysis method based on wavelet multi-scale analysis is utilized to provide quick and accurate acquisition for the size distribution of particles. The method may be used for real-time monitoring of the production of standard particle, detection of oil-in-water pollutants, granularity detection for milk products, study on particle structure in biological cells and the like. The system is simple, and analytical results are accurate.

Systems, methods, and devices are provided to determine an accurate neutron-gamma density (NGD) measurement for a broad range of formations, including low-hydrogen-index or low-porosity formations and formations with heavy elements. For example, such an NGD measurement may be obtained by emitting neutrons into a formation such that some of the neutrons inelastically scatter off elements of the formation and generate inelastic gamma rays. The neutrons and inelastic gamma rays that return to the downhole tool may be detected. Some characteristics of certain formations are believed to affect the fast neutron transport of the formations. Thus, if a formation has one or more of such characteristics, a correction may be applied to the count rate of neutrons, the count rate of inelastic gamma rays, or the neutron transport correction function, upon which the neutron-gamma density (NGD) may be determined.

Provided is a high-accuracy fast neutron reactor assembly few-group cross section obtaining method. The fine-group cross section of a fast neutron reactor assembly is calculated in the mode that point cross section data and multi-group data are combined, online calculation of an elastic scattering matrix is performed, a neutron transport equation is solved by using the fine-group cross section to obtain fine-group neutron-flux density, energy groups are merged on the basis, and accordingly few-group parameters of the fast reactor assembly are obtained. Due to the fact that the method directly uses the point cross section data, the elastic scattering resonance effect of a medium mass nuclide and the resonance interference effects of all nuclides are accurately considered. The neutron-flux density of a real system is adopted in the energy group merging process, and merging results are more accurate. The overall errors of fast reactor assembly few-group parameters calculated by adopting the method are within 1% compared with a reference value, and the method has higher accuracy.

Methods, apparatuses, and systems for detecting and classifying individual airborne biological and non-biological particles, in real time, based on particle size and polarized elastic scatter. Auto-fluorescence content may also be used along with particle size and polarized elastic scatter for further orthogonal classification. With polarized elastic scattering, the degree of linear or circular depolarization produced from particle morphology, refractive index, internal asymmetric structures and molecular optical activity can be used for classifying individual airborne particles. Alternatively, circular intensity differential scattering (CIDS) or linear intensity differential scattering (LIDS) can be used to discriminate individual particles.

A coherent confocal microscope for fully characterizing the elastic scattering properties of a nanoparticle as a function of wavelength. Using a high numerical aperture lens, two-dimensional scanning and a simple vector beam shaper, the rank-2 polarizability tensor is estimated from a single confocal image. A computationally efficient data processing method is described and numerical simulations show that this algorithm is robust to noise and uncertainty in the focal plane position. The measurement of the polarizability removes the need for a priori assumptions regarding the nanoparticle shape.

The present invention discloses an ultraviolet quasi-single pure-rotation Raman spectrum extraction-based all-day temperature measurement laser radar. The laser radar comprises a laser emitting unit, an optical receiving unit and a signal acquisition and control unit. The laser emitting unit emits the ultraviolet laser of 354. 82 nm in wavelength and the ultraviolet laser is adopted as a detection light source. The laser emitting unit sends a pulse laser beam to the atmosphere. The pulse laser beam and atmospheric particles interact to generate a series of discrete spectrum line scattering signals. The optical receiving unit receives the scattering signals through a telescope and then respectively and simultaneously extracts elastic scattering signals and quasi-single-branched anti-stoke pure-rotation Raman spectral line signals through three channels. The signal acquisition and control unit realizes the real-time acquisition and the inversion of signals, so that the normal and orderly operation of the entire laser radar system is ensured. According to the technical scheme of the invention, the signal-to-noise ratio of the system is enhanced, and the light-receiving path is optimized. The system stability is improved. The all-day detection of the atmospheric temperature, the aerosol space distribution and time evolution parameters is implemented.

Methods, apparatus, and compositions calibrate a bio-photonic scanner detecting selected molecular structures of tissues, nondestructively, in vivo. The apparatus may include a processor, memory, and scanner. The scanner directs light nondestructively onto tissue in vivo, then receives back a radiant response through a system of mirrors and lenses back into the detector. Software for controlling the scanner and processing its output may be calibrated using a synthetic material to mimic the radiant response of tissue. Calibration may account for background fluorescence and elastic scattering, mimicking skin tissue materials having substantially no Raman scattering response of interest. Dopants may be added to the matrix of white scan material to mimic selected molecular structures in tissue. Matrix materials include a dilatant compound, and dopants include biological materials as well as K-type polarizing film and other materials.