Abstract: A system and method include a sensor disposed adjacent a power actuated movable panel of a vehicle for detecting an approach of an operator to the power actuated movable panel and measuring at least one operator characteristic of the operator in proximity to the sensor. The system and method also include a controller in communication with the sensor to interpret sensor data of the operator from the sensor to determine the at least one operator characteristic to adjust a position of the power actuated movable panel based on the at least one operator characteristic.

Abstract: A sample observation device includes a flow cell in which a fluid containing samples flows, an irradiation unit configured to irradiate the samples flowing in the flow cell with planar light, an image formation unit having an observation axis inclined with respect to an irradiation surface for the planar light, and configured to form an image of observation light generated in the sample due to the irradiation with the planar light, a two-dimensional imaging element configured to capture a light image including at least a cross section of the fluid among light images according to the observation light formed by the image formation unit, and outputs image data, and an analysis unit configured to analyze a light intensity profile of the sample in a flow direction of the fluid on the basis of the image data.

Abstract: Systems, apparatuses, and methods for identifying and tracking objects (e.g., debris, particles, space vehicles, etc.) using one or more light detection and ranging (LIDAR)-based sensors are disclosed. Such systems, apparatuses, and methods may be particularly beneficial for detecting millimeter scale and/or sub-millimeter scale objects. Such systems, apparatuses, and methods may be used for detection of objects in space, in the atmosphere, or in the ocean, for example.

Abstract: The present disclosure provides a system and method for determining a range to an object in a fluid. The system includes a polarized light source directed to the object in the fluid, a first imaging sensor, a second imaging sensor, and at least one processor. The at least one processor characterizes a depolarization rate of the fluid and determines the range to the object. The method includes generating polarized light via a polarized light source, polarizing an imager relative to the polarized light, transmitting the polarized light from the polarized light source into the fluid, receiving reflected light from the object, characterizing a depolarization rate of the fluid, based, at least in part, on the reflected light, and determining the range to the object, based, at least in part, on the depolarization rate of the fluid.

Abstract: A monitoring device performs a method of detecting a need for maintenance of an exercise machine comprising a time-of-flight, ToF, sensor. The method comprises obtaining a measurement signal from the ToF sensor at a predefined operating condition of the exercise machine. Based on the measurement signal, the method determines a measured distance between the ToF sensor and a reflective element in the exercise machine. The measured distance has been found to be responsive to accumulation of deposits on the ToF sensor and is thus evaluated by the method to detect a need for cleaning. The method thereby enables preventive maintenance.

Abstract: A measurement method includes: (a) measuring an emission intensity for each wavelength of light detected from a plasma generated in a plasma processing apparatus at each different exposure time by a light receiving element; (b) specifying, with respect to each of a plurality of different individual wavelength ranges that constitutes a predetermined wavelength range, a distribution of the emission intensity in the individual wavelength range measured at an exposure time at which an emission intensity of a predetermined wavelength included in the individual wavelength range becomes an emission intensity within a predetermined range; (c) selecting a distribution of the emission intensity in the individual wavelength range from the distribution of the emission intensity specified in (b); and (d) outputting the distribution of the emission intensity selected for each individual wavelength range.

Abstract: A damage identification method based on cable force tests of a cable system and test error self-adaptive analysis is proposed to measure cable forces in prestressed steel structures and find out possible damage positions of the cable system. The method includes placing a laser velocimeter; measuring the vibration speed history data of the measuring point P on the cable by the laser velocimeter; calculating the cable force; calculating all the cable forces of the cable system through the same procedure; analyzing error between cables and finding out the possible damage of the cable or of the tie rod connected to the cable. The dynamic response characteristics of both in-plane and out-of-plane of a cable can be obtained through the method of the present invention. The self-verified more accurate results can be obtained, and the damage in a cable system can be determined according to error self-adaptive analysis.

Abstract: Apparatus and associated methods relate to determining metrics of a cloud atmosphere using time difference measurements. A light projector projects a pulse of light into a cloud atmosphere, and a light sensor detects a portion of the projected pulse of light backscattered by the cloud atmosphere. A backscatter coefficient is calculated based on peak amplitude of the detected portion. An optical extinction coefficient is calculated based on a time difference between a peak time and a post-peak time, which correspond to times at which the peak amplitude of the detected portion occurs and at which the detected portion equals or crosses a sub-peak threshold, respectively. In some embodiments, a logarithm amplifier is used to facilitate processing of signals of widely varying amplitudes. In some embodiments, the sub-peak threshold is calculated as a fraction of the peak amplitude of the detected portion.

Abstract: A Raman spectrometric imaging method, including: placing a sample on a two-dimensional translation stage; emitting a first light beam by a first optical comb light source; dividing the first light beam into a pump light beam and a depletion light beam to illuminate the sample; guiding the pump light beam to illuminate a region of the sample to excite molecules of the sample in the region; guiding the depletion light beam to the region of the sample to make excited molecules at a periphery of the region to return into a vibrational ground state; emitting a second light beam as a probe light beam by a second optical comb light source to the remaining excited molecules to generate a CARS signal; recording the CARS signal for imaging; moving the two-dimensional translation stage to scan other regions of the sample to form an image of the sample.

Abstract: A system and method include scanning a light detection and ranging (LIDAR) device through a range of orientations corresponding to a scanning zone while emitting light pulses from the LIDAR device. The method also includes receiving returning light pulses corresponding to the light pulses emitted from the LIDAR device and determining initial point cloud data based on time delays between emitting the light pulses and receiving the corresponding returning light pulses and the orientations of the LIDAR device. The initial point cloud data has an initial angular resolution. The method includes identifying, based on the initial point cloud data, a reflective feature in the scanning zone and determining an enhancement region and an enhanced angular resolution for a subsequent scan to provide a higher spatial resolution in at least a portion of subsequent point cloud data from the subsequent scan corresponding to the reflective feature.

Abstract: An efficient method of scanning is provided that may be used for treatment, analysis, inspection and testing physical objects and spaces. High precision, resolution and throughput of scanning are achieved by employing a dual motion of probing devices and scanned objects. A probing device spins with high speed about an axis of spinning directed towards a scanned object. Concurrently, the spinning axis is set in a relatively slow motion with respect to the scanned object. Both the spinning of the probing and the motion of the spin axis are implemented in a controlled and predetermined way to achieve objectives of scanning. Accordingly, arbitrary large and shaped objects may be efficiently scanned with high precision and throughput.

Abstract: A LIDAR system, including a transmitting unit that includes a polarization device, the polarization device being configured to set a polarization of a scanning beam, a receiving unit that is configured to receive the scanning beam after it has been reflected on a point in the surroundings of the LIDAR system, the receiving unit including a polarization recognition device that is configured to recognize a polarization of the reflected scanning beam, and an evaluation unit that is configured to ascertain a polarization difference, based on a difference between the polarization that is set by the transmitting unit and the polarization that is recognized by the receiving unit.

Abstract: An underwater data capture and transmission system has a base configured to sink in water, at least one sensor configured to capture data while submerged in water, a processing unit configured to receive data collected by the sensor, and a variable buoy. The variable buoy has a ballast system configured to adjust a depth of the variable buoy in the water, and a communication device configured to transmit data to a remote communications device. The system further has at least one tether connecting at least the base, the processing unit, and the variable buoy.

Abstract: Methods and systems provide a non-ionizing alternative to conventional mammography X-ray techniques, which expose patients to ionizing radiation, for breast cancer tumor detection, using a miniaturized (wafer scale) array of ultra wide band (UWB) radio frequency (RF) sensors operating at 60 GHz (non-ionizing—no X-ray type accumulative radiations) that have capability to use both linear and polarized sensors, tomography, and suppression of scattering for improved imaging. Coding techniques provide significant processing gain that is essential for the large attenuation of transmitted signals in breast tissue operating at these high frequencies. The increased bandwidth of UWB RF detection provides better depth resolution of breast and body tissue. Using polarization improves detection of abnormal tissues.

Abstract: A light detection and ranging (LIDAR) system includes a transceiver, a laser source coupled to the transceiver, a time-division multiplexing (TDM) circuit, and one or more processors. The TDM circuit is configured to generate a plurality of first signals. The one or more processors are configured to control the laser source to provide an optical beam to a first input optical channel of a plurality of input optical channels of the transceiver during a first time slot, based on the optical beam provided to the first input optical channel, control the transceiver to send a first reflected beam and a second reflected beam to the TDM circuit through a first output optical channel of a plurality of output optical channels of the transceiver, and based on a control signal provided to the TDM circuit, control the TDM circuit to select the plurality of first signals during the first time slot.

Abstract: The invention discloses a device for simulating an evolution process of an internal combustion engine exhaust particle flow for reducing automotive emissions, and the device comprises an exhaust source; an exhaust channel, comprising a plurality of sections of cylindrical tubes with specified length that are fixedly connected; a soluble organic compound generator, used to produce soluble organic compounds; a carbon particle generator, used to produce carbon particles. The device for simulating the evolution process of an internal combustion engine exhaust particle flow for reducing automotive emissions has the advantages of simple structure and low cost; controls the mixing concentration of soot particles and soluble organic compounds through various adjustment methods to obtain a suitable mixed aerosol, so as to better simulate the exhaust particle flow of an internal combustion engine.

Abstract: The present disclosure discloses an optical sensor for liquid or gas analysis including a light source that emits measurement radiation and a housing, wherein the light source is arranged in the housing, and wherein the light source radiates measurement radiation out of the housing in a solid angle. The optical sensor further includes a signal light source that emits visible light from the housing in at least the same solid angle.

Abstract: An airfield visibility monitoring system may include a measurement unit to emit one or more pulses of electromagnetic radiation along an aircraft glideslope associated with a runway and detect backscattered radiation from the glideslope associated with the emitted pulses. The measurement unit may further determine round-trip times between emission of the one or more pulses and detection of the backscattered radiation. The system may further include a controller. The controller may determine values of a visibility metric for multiple distances from the measurement unit along the glideslope based on the detected backscattered radiation and round-trip times, determine values of the visibility metric for multiple altitudes based on the values of the visibility metric along the glideslope, and direct an airfield communication unit to broadcast values of the visibility metric for at least some of the altitudes.

Abstract: It is disclosed optical communication system and method capable or monitoring underwater information in real time. An optical communication system may be configured to include a first optical communication module configured with a photographing unit which is installed on objects moving underwater and photographs underwater pictures or images and a first optical transceiver module for transmitting and receiving image information for the underwater pictures or images photographed in the photographing unit; a second optical communication module for receiving the image information from the first optical transceiver module of the first optical communication module and transmitting the image information to an external device or a displaying unit.

Abstract: An optical particle sensor apparatus is equipped with a housing (MD) having an optical exit region (OF); an optical emitter device (LD) in the housing that is set up to emit an optical measurement beam (OB) for capturing particles; a focusing lens device (LE) in the housing for directing the optical measurement beam through the optical exit region to outside the housing in a focus region (FA), within which particle capturing is performable; an optical detector device (DD) arranged in the housing and set up to capture the measurement beam (OB?) scattered by particles (P) and to output information produced using an algorithm relating to the presence of the particles; and a controllable adaptation device (C, E), which is set up to adapt at least one optical property of the lens device and/or of the optical emitter device and/or of the optical detector device based on an input signal (ES; ES?) that provides information relating to a presence and to optical properties of an external optical window (EF) arranged be

Abstract: A system and method include scanning a light detection and ranging (LIDAR) device through a range of orientations corresponding to a scanning zone while emitting light pulses from the LIDAR device. The method also includes receiving returning light pulses corresponding to the light pulses emitted from the LIDAR device and determining initial point cloud data based on time delays between emitting the light pulses and receiving the corresponding returning light pulses and the orientations of the LIDAR device. The initial point cloud data has an initial angular resolution. The method includes identifying, based on the initial point cloud data, a reflective feature in the scanning zone and determining an enhancement region and an enhanced angular resolution for a subsequent scan to provide a higher spatial resolution in at least a portion of subsequent point cloud data from the subsequent scan corresponding to the reflective feature.

Abstract: A lidar system includes a lighting module configured to (i) select a wavelength from among a plurality of wavelength values, for a particular time period, and (ii) emit light at the selected wavelength. The lighting module emits light at different wavelengths during at least two adjacent periods of time. The lidar system further includes a scanner configured to direct the pulse of light to illuminate a respective region within a field of regard of the lidar system and a receiver module configured to (i) receive a light signal and (ii) determine whether the received light signal includes the light emitted by the lighting module and scattered by a remote target, based at least in part on the wavelength selected by the lighting module.

Abstract: In one example, a LIDAR device includes a light sources that emits light and a transmit lens that directs the emitted light to illuminate a region of an environment with a field-of-view defined by the transmit lens. The LIDAR device also includes a receive lens that focuses at least a portion of incoming light propagating from the illuminated region of the environment along a predefined optical path. The LIDAR device also includes an array of light detectors positioned along the predefined optical path. The LIDAR device also includes an offset light detector positioned outside the predefined optical path. The LIDAR device also includes a controller that determines whether collected sensor data from the array of light detectors includes data associated with another light source different than the light source of the device based on output from the offset light detector.

Abstract: There is provided a cell image evaluation device, method, and program to appropriately evaluate the state of a stem cell colony according to different changes in form of respective local regions of the cell colony. There are included a low magnification image acquisition unit 20 that acquires a cell image by imaging cells; a cell evaluation unit 23 that evaluates the cell image; and a local region information acquisition unit 21 that acquires the specific information of a local region in a colony region of the cells in the cell image. The cell evaluation unit 23 determines, for each local region in the colony region, an evaluation method for a cell image in the local region based on the specific information of the local region, and evaluates the cell image of the local region using the determined evaluation method.

Abstract: Described herein is a method for enhancing image data that includes dividing an image into multiple regions. The method includes measuring variations in pixel intensity distribution of the image to determine high pixel intensity variations for identifying an intensity-changing region. The method includes calculating a histogram of intensity distribution of pixel intensity values for the intensity-changing region without calculating a histogram of intensity distribution of pixel intensity values for each region of the multiple regions. The method also includes determining a transformation function based on the intensity distribution for the intensity-changing region. The method includes applying the transformation function to modify an intensity for each pixel in the image to produce an enhanced image in real time. The method also includes detecting in the enhanced image a horizon for providing to an operator of a vehicle an indication of the horizon in the image on a display in the vehicle.

Abstract: A lidar system includes a lighting module configured to (i) select a wavelength from among a plurality of wavelength values, for a particular time period, and (ii) emit light at the selected wavelength. The lighting module emits light at different wavelengths during at least two adjacent periods of time. The lidar system further includes a scanner configured to direct the pulse of light to illuminate a respective region within a field of regard of the lidar system and a receiver module configured to (i) receive a light signal and (ii) determine whether the received light signal includes the light emitted by the lighting module and scattered by a remote target, based at least in part on the wavelength selected by the lighting module.

Abstract: The invention concerns an aircraft propulsion control system in which a gas turbine engine has an actuable flow opening for control of flow to or from a portion of the engine. One or more sensor is arranged to sense a condition indicative of vapor trail formation by the exhaust flow from the engine. A controller is arranged to control actuation of the flow opening so as to reduce the efficiency of the engine upon sensing of said condition by the one or more sensor. In one example, the flow opening is a variable area fan nozzle.

Abstract: The automatic analysis device measures time sequential data on a scattered light amount as reaction process data, and quantitatively determines the concentration of an analyte from a change in light amount. The automatic analysis device has a function of selecting reaction process data to be used for quantitative determination from the reaction process data obtained by measurement using a plurality of light receivers at different angles. As a result of using this function, data is selected from the reaction process data obtained by measurement using the plurality of light receivers at different angles in accordance with the concentration of the analyte and whether the priority is given to high sensitivity in the case where sensitivity is prioritized or a dynamic range, and the result of the quantitative determination is displayed.

Abstract: The invention relates to a method for light detecting and ranging (LIDAR) measurement of speeds, in which a laser beam is directed at the medium to be measured, and radiation which is subsequently emitted from the medium (16) is measured by a detector. In order to optimize the measurement, a spatial measurement range can be selected by activation and/or deactivation of the detector for at least one predetermined or regulated time duration of less than about 500 ?s after emission of a laser pulse to the medium to be measured. Furthermore, a direct reception Doppler LIDAR apparatus can be used to perform the method.

Abstract: An apparatus and method for managing a liquid volume in a container includes a detector for detecting liquid volume changes in the container during a first preset period, a first determiner for determining whether the changes are lower than the first preset threshold value, and a presenter for presenting the first prompt information in case the changes are lower than the preset threshold value.

Abstract: Provided is a device for concentrating and separating cells, which has a function for continuously concentrating cells; a function for then continuously arranging the concentrated cells in predetermined regions of a flow path; a function for simultaneously identifying shape and fluorescent emission in one-cell units on the basis of cell concentration and purification images, which serve to continuously separate and purify cells that have different properties in that they are either attracted to or repelled by an induction electrophoresis force of a predetermined frequency; and a function for identifying cells on the basis of this shape and fluorescent emission information and thereby separating and purifying the cells.

Abstract: There is provided an inside observation apparatus of an endoscope and the like which can perform an inside observation for irradiating an illumination light to a minute area of a surface of an object (for example, a living tissue) having a light scattering property and detecting a back-scattered light of the illumination light, can increase a detected light amount by a simply and low cost configuration by making an area of a detection region larger than an illumination region, and can reduce a time necessary to detect an body (for example, a blood vessel) to be observed and detect a region deeper than a conventional region.

Abstract: A method of optically determining the presence of volcanic ash within a cloud comprises emitting a circularly polarized illuminating beam within a cloud and analyzing backscatter light to identify the presence of volcanic ash within the cloud. The method further includes determining the degree to which the cloud has altered the polarization state of the emitted beam. The index of refraction of the backscatter light and the opacity of the backscatter light are also analyzed.

Abstract: [Subject] To provide laser Doppler blood flow measuring method and device which achieve multi-dimensional measurement efficiently at a high degree of accuracy over a wide range with a simple optical system and device. [Solving Means] Laser light from a semiconductor laser 12 is split and formed into sheet lights Ls using a cylindrical lens 22, and the sheet lights Ls are crossed with each other at a predetermined position. A lens system 30 configured to form an image of scattered lights into a linear shape at a linear irradiation site Lx where the sheet lights Ls cross with each other is provided. An optical fiber array 32 having a plurality of optical fibers 34 is provided at an image-forming position of the lens system 30. Avalanche photodiodes 42 configured to convert the scattered lights which are shifted in frequency by the Doppler effect caused by the blood flow into electric signals for the each optical fiber 34 are provided.

Abstract: A method of using LIDAR on an airborne vehicle is described. A beam of radiation is transmitted to target areas at least one of above, below, and in front of the airborne vehicle, the target areas including particles or objects. Scattered radiation is received from the target areas. Respective characteristics of the scattered radiation are determined. An air turbulence factor or characteristics are determined from the respective characteristics. The airborne vehicle is controlled based on the air turbulence factor, such that turbulence experienced by the airborne vehicle is minimized. Alternatively, the airborne vehicle is controlled based on the characteristics to avoid colliding with the one or more objects. In another example, the airborne vehicle is controlled based on the characteristics to reduce headwind or increase tailwind, and substantially reduce a carbon footprint of the aircraft.

Abstract: An inspection method and an inspection device, or apparatus each capable of conducting composition analysis of a defect detected by elastic or stokes scattered light, an inspection surface or defect on the surface of the inspection surface, or a defect on the surface of the inspection object and its internal composition. A surface inspection method for optically detecting elastic or stokes scattering or inelastic or anti-stokes scattered light from inside the surface of the inspection object, for detecting existence of defects of the inspection object and features of the defects, for detecting positions of the detected defects on the surface of the inspection object, classifying and analyzing the detected defects in accordance with their features on the basis of the positions of the defects and the features of the defects or the classification result of the defects.

Abstract: An optical system includes a radiation source, a radiation-illuminating device, and a radiation-collecting device. The radiation source is configured to generate radiation. The radiation-illuminating device is optically coupled to the radiation source and configured to direct and focus the radiation obliquely with respect to an optical axis thereof onto a sample. The radiation-collecting device is configured to collect back-scattered radiation scattered from the sample and spatially separated from noise radiation. Associated apparatus and method are also described.

Abstract: A method of optically determining the presence of volcanic ash within a cloud comprises emitting a circularly polarized illuminating beam within a cloud and analyzing backscatter light to identify the presence of volcanic ash within the cloud. The method further includes determining the degree to which the cloud has altered the polarization state of the emitted beam. The index of refraction of the backscatter light and the opacity of the backscatter light are also analyzed.

Abstract: A weapon-locating ladar system estimates a backward trajectory of an airborne target by using flow field measurements to follow the wake turbulence trailing the airborne target from a position at which the target is detected backwards until the wake is no longer observable. The system may use the backward trajectory to estimate the point-of-origin of the target. The system may also use the flow field measurements along the backward trajectory to classify the target. Target classification may be used to refine the point-of-origin estimate, to influence counter-fire or to adapt the flow field measurements.

Abstract: A method of using a light detection system for increasing the accuracy of a precision airdrop is described. Radiation is transmitted to target areas between an airborne vehicle and a dropzone target. Scattered radiation is received from the target areas. Respective wind characteristics are determined from the scattered radiation and a wind velocity map is generated, based on the respective wind characteristics, between the airborne vehicle, and at least the dropzone target. An aerial release point for the precision airdrop is computed based on the generated wind velocity map and a location of the dropzone target.

Abstract: A method and apparatus are disclosed for providing image data for generating an image of a region of a target object. The method includes the steps of providing incident radiation, focusing the radiation downstream or upstream of a target object and via at least one detector located downstream of a focusing element, detecting an intensity of radiation scattered by the target object at an observation plane offset from a back focal plane associated with the focusing element.

Abstract: An apparatus for identifying defects within the volume of a transparent sheet, such as a glass sheet, is provided. The apparatus includes an illumination device that directs incident light onto at least a portion of a surface of the sheet so as to illuminate the sheet, and an image detector onto which the light backscattered from the sheet is directed to image the sheet. The apparatus generates at least two interference images under different capturing conditions in order to perform identification of defects by evaluating the at least two interference images.

Abstract: The present invention relates to a method for determining at least one gas condition at a location in a combustion chamber of a power plant or a combined heat and power plant by means of a laser pulse. The method comprises emitting (S1) the laser pulse into the chamber, determining (S2) a first point of time at which the laser pulse is emitted into the chamber, detecting (S3) laser light backscattered by gas molecules at the location in the chamber, determining (S4) a second point of time at which the laser light backscattered by the gas molecules is detected, determining (S5) the location based on the first point of time, the second point of time, and a pulse length of the laser pulse, and determining (S5) the at least one gas condition at the location based on at least one characteristic of the backscattered laser light detected at the second point of time. A gas measurement system and a combustion system are also presented herein.

Abstract: An optical interrogation system, e.g., an OFDR-based system, measures local changes of index of refraction of a medium contained within a light guiding tube and includes an optical interferometric interrogator, optical detection circuitry, and a data processor. The data processor initiates a sweep of the light source and guide light from an interrogating light source into a medium contained by a tube which restricts movement of particles provided into the tube, where the medium is subjected to a driving force that overcomes resistance to movement of particles through the medium in the tube. The optical interferometric interrogator provides an optical interference pattern associated with a group of particles having moved in the tube as a result of the driving force. Based on the optical interference pattern, the data processor identifies a current location of the group of particles in the tube.

Abstract: The invention relates to a method for determining the size d of a transparent particle, according to which method the particle is illuminated with light from a light source, a radiation detector measures a time-resolved intensity profile of light of the light source scattered by the particle, a reflection peak (10) and a refraction peak are determined in the intensity profile and the size d of the particle is determined based on a time difference between the reflection peak (10) and the refraction peak.

Abstract: A LIDAR device may transmit light pulses originating from one or more light sources and may receive reflected light pulses that are then detected by one or more detectors. The LIDAR device may include a lens that both (i) collimates the light from the one or more light sources to provide collimated light for transmission into an environment of the LIDAR device and (ii) focuses the reflected light onto the one or more detectors. The lens may define a curved focal surface in a transmit path of the light from the one or more light sources and a curved focal surface in a receive path of the one or more detectors. The one or more light sources may be arranged along the curved focal surface in the transmit path. The one or more detectors may be arranged along the curved focal surface in the receive path.

Abstract: In one aspect, methods of determining a size distribution of water droplets in a cloud are described herein. In some embodiments, a method of determining a size distribution of water droplets in a cloud comprises sampling a depth of the cloud with a beam of electromagnetic radiation, measuring a scattering signal of the electromagnetic radiation returned from the cloud over a range of field of view angles to provide a measured scattering curve [ptotal(?)], removing a portion of the measured scattering curve, replacing the removed portion with an extrapolation of the remaining measured scattering curve to provide an estimated scattering curve, and determining a first estimate droplet size distribution [n(1)(D)] from the estimated scattering curve.

Abstract: A particle detection system including; at least one light source adapted to illuminate a volume being monitored at at least two wavelengths; a receiver having a field of view and being adapted to receive light from at least one light source after said light has traversed the volume being monitored and being adapted to generate signals indicative of the intensity of light received at regions within the field of view of the receiver; a processor associated with the receiver adapted to process the signals generated by the receiver to correlate light received at at least two wavelengths in corresponding regions within the field of view of the receiver and generate an output indicative of the relative level of light received at the two wavelengths.

Abstract: A beam detector (10) including a light source (32), a receiver (34), and a target (36), acting in co-operation to detect particles in a monitored area (38). The target (36), reflects incident light (40), resulting in reflected light (32) being returned to receiver (34). The receiver (34) is a receiver is capable of recording and reporting light intensity at a plurality of points across its field of view. In the preferred form the detector (10) emits a first light beam (3614) in a first wavelength band; a second light beam (3618) in a second wavelength band; and a third light beam (3616) in a third wavelength band, wherein the first and second wavelengths bands are substantially equal and are different to the third wavelength band.

Abstract: A method for detecting atmospheric icing potential comprises emitting, by a lidar (light detection and ranging) entity (108a, 108b) such as a Doppler lidar entity, electromagnetic radiation to the atmosphere and receiving radiation backscattered from the aerosol, such as a cloud, present in the atmosphere (304), determining an indication of signal intensity, such as the CNR (carrier-to-noise ratio), on the basis of the received backscattered signal relative to one or more distances such as heights from a predetermined basic level such as the location of the lidar (306), comparing the indication of signal intensity with at least one predetermined reference in order to obtain an indication of the likelihood of cloud (110) presence at said one or more distances (308), and determining an indication of the icing potential at said number of distances on the basis of the comparison and an indication of the temperature at said one or more distances (310). An arrangement for executing the method is presented.