On-line detection of mesophase particles employs a laser diode light source to illuminate a target area with a pulsed laser linearly or circularly polarized probe beam. Analysis of images determines extent of presence the birefringent mesophase particles, which are precursors to coking in catalytic hydrocracking processes. The inherently polarized low-coherence, unfocused but sufficiently collimated, pulsed laser beam yield sharp imaging with high depth of field of very small mesophase particles that are present in a moving, dark reactor liquid environment.

A polarization inspector for inspecting an inspection target, the polarization inspector having a polarization divider for spatially dividing at least a reflected beam of light from the inspection target by irradiating an illumination beam into divided beams of lights mutually different in polarization direction; one or more optical receivers for receiving the divided beams of lights and generating an image signal based on the divided beams of lights; and a processor for calculating at least one of an elliptical azimuth angle, a polarization degree and a polarization component intensity from the image signal.

A novel methodology for detecting cloud particles is disclosed herein. This methodology exploits the optical glory phenomenon. According to one embodiment, a method for detecting clouds includes receiving data from a sensor which is configured to measure polarization of scattered light in a direction substantially opposite to the direction of incident light, and identifying, from the received sensor data, a cloud based on the polarization of the scattered light.

In one aspect, the present invention generally provides methods for characterizing mineralization of a material, e.g., a biomaterial, by illuminating the material with radiation and analyzing radiation scattered from the material in response to the illumination. For example, in some embodiments, a material can be illuminated with polarized radiation at a plurality of wavelengths and the elastically scattered radiation corresponding to two or more of those wavelengths can be collected at two polarizations: one parallel and the other perpendicular to the illumination polarization. A differential intensity of the scattered radiation at the two polarizations can be analyzed as a function of wavelength to obtain information regarding the morphology of mineral deposits in the sample. Further, the total scattered radiation can be analyzed to derive information regarding the level of mineralization.

Provided are a cooperative polarization skylight background radiation measurement device and method, belonging to the field of polarized radiation remote sensing. The device includes a measurement probe, a lower computer control system, a two-dimensional turntable, a base and data transmission interface, as well as an upper computer. The method includes the following steps: the cooperative skylight background radiation polarization measurement device is initialized, a polarization wheel is returned to a zero position, and dark noise is collected by a double-path spectrometer; then a measurement mode is selected for measurement; and finally, spectral polarization data of each wave band acquired by the double-path spectrometer and a division-of-focal plane polarization camera is transmitted to the upper computer through a data line, original spectral light intensity data is calculated according to a measurement principle, and finally a degree of polarization and an azimuth angle of polarization are obtained.

Provided is an apparatus for detecting smoke based on polarization. The apparatus includes a chamber into which smoke is introduced, a detection unit comprising a light-emitting unit configured to emit light beams having a plurality of different wavelengths into a space in the chamber, and a light-receiving unit configured to receive scattered light from a plurality of light sources, a control unit configured to control an operation of the detection unit, and a fire determination unit configured to distinguish between fire smoke and non-fire analogous smoke by detecting and analyzing a light-receiving signal received by the light-receiving unit, in which horizontal polarization and vertical polarization are applied to the plurality of light sources of the light-emitting unit and the light-receiving unit.

Proposed is an inspection device that is provided with: an illuminating optical unit that irradiates a discretionary region of a sample with light; a control unit that gives instructions to the illuminating optical unit; and at least one detection unit that detects light transmitted from the sample. The illuminating optical unit includes a light source unit that generates light, and an electrooptic element unit to which the light generated by the light source unit is inputted, and on the basis of the instructions given from the control unit, the electrooptic element unit adjusts the light to be in a desired polarization state, said light having been generated by the light source unit, and irradiates the sample with the light.

A polarimeter includes an integrated device with an array of antennas including multiple column pairs. Each column pair has two columns, and each column in each column pair includes multiple antennas. A first column of each column pair in the array scatters a first polarization component of an incident radiation, and a second column of each column pair in the array scatters a second polarization component of the incident radiation. The scattered fields of the column pairs interfere constructively in a direction depending on the polarization of the incident radiation, resulting in maximal intensity at a certain point in space for a specific polarization state. Multiple column pairs in parallel and oriented at angles with respect to each other can be used to scatter different polarization components of the incident radiation directionally to different points in space. Detectors are positioned with respect to the integrated device to detect polarization components.

An attenuation meter is provided for use in a water environment. In operation, a transmitter of the meter transmits a laser pulse focused to a size at a predetermined range. A receiver of the meter images a focused spot to minimize unwanted light back scattering and avoid diffractive spreading within the back scattering region. Filtering the angular region can further reject scattered light. The filtered light is received, measured and processed by a oscilloscope as pulse averages. The meter also includes a photodetector to measure a diffuse attenuation coefficient. The output voltage of the photodetector is measured and processed by the oscilloscope that produces an average voltage over a preset number of pulses. A controller best fits voltage to time dependence to produce the diffuse attenuation coefficient. Only the shape of the receiver time dependence is required to provide the diffuse attenuation coefficient measurement.

An authentication structure and an authenticating method using the same are provided. The authentication structure includes a plurality of input couplers that generate surface plasmons by being selectively coupled to lights because the plurality of input couplers are different in terms of at least one of a geometric structure and an arrangement, and an output coupler that outputs a speckle pattern based on the surface plasmons.