Abstract: In an embodiment, a pressure transducer includes a first portion, a second portion, and a third portion. The third portion is positioned in a cavity contained in the second portion. In addition, a seal is placed in the cavity. The first portion and second include provisions for applying a downward pressure on the third portion when the first portion and the second portion are joined. The downward pressure is applied by the third portion to the seal the cavity. The first portion also includes a stop and the second portion also includes a snap member. The snap member includes a prong that contains a first edge and a second edge. The snap member allows movement of the first portion after the first edge of the prong meets the stop and restricts movement of the first portion after the second edge of the prong meets the stop.

Abstract: A semiconductor pressure sensor for measuring an external pressure exerted on the sensor, comprises a membrane, and a bridge comprising a first and a second resistor pair, arranged on a first resp. second side portion of the membrane. The first resistor pair comprises a first and a second resistor (R1, R2) comprising elongated piezo-resistive strips connected in series, and located closely together, such that R1 and R2 have substantially the same temperature. The sensor has a reduced sensitivity to: a temperature gradient over the membrane, and optionally also a non-uniform stress gradient caused by packaging and a inhomogeneous disturbing electric field perpendicular to the sensor. The piezo-resistive strips of the first and second resistor may be oriented in orthogonal directions of maximum piezo-resistive coefficients. A second bridge may be added outside the membrane, for compensating for package pressure.

Abstract: An automobile turbocharger examination device is provided. A connection tube set connects an outlet tube of a turbocharger and an inlet tube of an engine to define a detection channel which includes a hard tube portion and a flexible tube portion which is provided for being connected among the hard tube portion, the outlet tube and the inlet tube. The examination device is for being connected between the hard and flexible tube portions. A first connection end of a connection tubular body includes at least one connection tube. One of the at least one connection tube of the first connection end is for being communicably connected with the flexible tube portion, and a second connection end of the connection tubular body is for being communicably connected with the hard tube portion. A pressure-detecting channel is for detecting pressure.

Abstract: A pipeline apparatus comprising a flexible pipe body and a detection apparatus. The flexible pipe body includes an optical fibre extending at least partially along the length of the flexible pipe body, the optical fibre being encased in a metal tube. The detection apparatus comprises an optical sensor and an electrical sensor. The optical sensor is coupled to a first end of the optical fibre, the optical sensor being arranged to inject optical pulses into the optical fibre and to detect scattered or reflected light. The electrical sensor is coupled to a first end of the metal tube and to detect variation of an electrical impedance between the first end of the metal tube and a separate terminal. Variation of the scattered or reflected light, or impedance variation, is indicative of a potential pipe body defect.

Abstract: A fluorescent dye in combination with an aviation functional fluid. The fluorescent dye is present in the functional fluid from about 0.0001% by weight to about 1% by weight. A method of detecting a leak in an aviation mechanical system that includes a functional fluid with a fluorescent dye. The method would include irradiating select areas of an airplane with a select spectrum of light, and observing an emission from the fluorescent dye.

Abstract: The invention relates to a system (1) and to a corresponding method for tank leakage diagnosis. The system (1) comprises a fuel tank (3), a pressure source (5, 9), and a pressure sensor (7). The pressure source (5, 9) is configured to increase the pressure in the fuel tank (3). The pressure sensor (7) is configured to detect the pressure progression at the fuel tank (3). The system (1) is configured to seal the fuel tank (3) in a gas-tight manner such that the fuel tank (3) can be used as a pressure store. Furthermore, the system (1) is configured to conclude, independently of a current operation of the pressure source (5, 9) based on the determined pressure progression at the fuel tank (3), that a leak is present.

Abstract: Systems, devices, and methods for leak testing surgical conduit grafts or valved conduits such as aortic-valved conduits with a pressurized gas such as air. Air is non-destructive and especially useful for leak testing conduits that have coatings or sealants that may be functionally impacted when exposed to fluids such as water or saline. Open ends of the conduit are clamped and sealed, and a pressurized gas introduced into an inner lumen thereof. A change in mass flow rate is measured to quantify the leakage. One end of a tubular conduit may be clamped to a fixed manifold, and the opposite end to a manifold slidably mounted to accommodate any conduit elongation when pressurized. The clamping and sealing structure may be pneumatic and/or mechanical, and complementary contoured clamp members may be used to seal a scalloped external sealing ring of an aortic conduit.

Abstract: Example apparatus and methods for performing measurements on an optical device are described for characterizing the optical device. An interrogating laser light source generates light at multiple different wavelengths during a single sweep of the laser light source. One or more optical interferometric interrogators are connected to the interrogating laser light source and connectable to the optical device such that light from the laser is coupled to the optical device and light from the optical device is received by the one or more optical interferometric interrogators in multiple different directions along a number of optical interferometric measurement paths. Optical detection circuitry detects an optical interference pattern, for each of the number of optical interferometric light paths, generated during the single sweep of the interrogating laser light source.

Abstract: A monitoring system for a gearbox containing a lubricant is disclosed. The monitoring system may include a first sensor configured to measure a concentration of debris particles in the lubricant, a second sensor configured to generate data indicative of a deterioration of the gearbox, and a controller in communication with the first and second sensors. The controller may be configured to estimate a concentration of debris particles in the lubricant based on the data from the second sensor using a mathematical function, and estimate a remaining useful life of the gearbox based on a difference between concentration of debris particles measured by the first sensor and concentration of debris particles estimated to be in the lubricant.

Abstract: The present disclosure provides a testing apparatus of an auxiliary belt system. The testing apparatus of the auxiliary belt system includes: a tester bracket, a torque pulse simulation motor mounted to the tester bracket, a crankshaft pulley mounted to the tester bracket and rotated by operations of the torque pulse simulation motor, an auxiliary system mounted to the tester bracket, connected to the crankshaft pulley through a belt and rotated by rotation of the crankshaft pulley and a controller controlling operations of the torque pulse simulation motor.

Abstract: An apparatus for estimating a crank angle when an engine stops includes a crank sensor generating an output signal indicating a rotational angle of a crankshaft. A resolver generates an output signal indicating a rotor absolute angular position of a motor which is connected to the engine to transmit power. A controller is configured to store output signal data of a crank sensor and output signal data of the resolver until the engine stops, and determines the crank angle based on motor reverse rotation information from the stored crank sensor output signal data and the stored resolver output signal data when the engine stops completely.

Abstract: A temperature and pressure probe (40) comprising an elongate outer tube (42) and elongate inner tube (56). Each tube having a peripheral wall (44, 58), a first open end (46, 60) and a second closed end (48, 62); the outer tube thereby defining an outer cavity (52) and the inner tube defining an inner cavity (66). The inner tube is located wholly within the outer cavity and is spaced from the outer peripheral wall (44) and second end (48). A temperature sensor (70) is located in the inner cavity. A pressure sensor (68) is located in the outer cavity. A vent pipe (76) is coupled between the inner peripheral wall and the outer peripheral wall, the vent pipe having a first end open to the inner cavity (66) and a second end open to vent outside the probe (40).

Abstract: Described is a wheel service machine (1) comprising: a shaft (3) rotating about a relative longitudinal axis (A), and a contact element (4), connected to the shaft (3) for rotating integrally with it and designed to make contact with the rim (2a) supported by the shaft (3); a locking device (5), which can be removably coupled to the shaft (3) and designed to slide relative to the shaft (3) along the longitudinal axis (A) and lock the rim (2a) interposed between the contact element (4) and the locking device (5); a fastening element (6) movably connected to the shaft (3) for moving parallel to the longitudinal axis (A) and designed for coupling with the locking device (5), for pulling it in movement; actuator (7) positioned on the machine and connected to the fastening element (6), wherein the locking device (5) comprises an emitter (8) designed for generating a wireless control signal, received by a wireless signal receiver (9) connected to the actuator (7), activates them for moving the locking device (5).

Abstract: A rigidity measurement device of a tread ring comprises a support jig for detachably holding a tread ring unit. The support jig has an open part for deformably exposing a measurement area, which is one portion of the tread ring, to the exterior, and a restraining part for essentially non-deformably restraining a non-measurement area, which is an area other than the measurement area of the tread ring. The restraining part inhibits deformation of the non-measurement area, whereby stress is no longer generated in the non-measurement area and the rigidity of the measurement area alone can be measured.

Abstract: An energy-efficient industrial sensor is provided that optimizes power consumption based on characteristics of the requirements of the sensing application in which the sensor is used. Operating parameters of the sensor, such as sensing range, operating frequency, response time, noise immunity, or other such parameters, can be scaled to suit the sensing and response requirements and environmental conditions of the sensing application. This allows the sensor to consume less energy when used in sensing applications that do not require peak sensor performance. In some embodiments, the sensor can measure the environmental or machine operating conditions in its immediate vicinity and dynamically scale its operating parameters based on the measured information. By down-scaling the sensor's operating parameters from their maximum performance levels where appropriate, the overall energy footprint of a network of sensors can be reduced.

Abstract: A vehicle closure cycling device is provided. The device includes a fixture, a first actuator mounted to the fixture and displaceable to open the vehicle closure and a second actuator mounted to the fixture and displaceable to close the vehicle closure at a predetermined closing speed. The device also includes a controller configured to cycle the first actuator and the second actuator in sequence to repeatedly open and close the vehicle closure.

Abstract: A mechanical part-stream sampler includes a housing positionable over a conveyor belt from which material is to be sampled. The housing encases one or more cutter arms and adjustable cutters. The cutter arms rotate 360 degrees such that the cutters extract a sample of material from the conveyor belt and deposit the sample in a discharge chute in the housing for later analysis. A programmable logic controller and human machine interface screen can be used to operate the sampler and to control the timing and speed of the cutter arms.

Abstract: Devices, systems and methods including a sonicator for sample preparation are provided. A sonicator may be used to mix, resuspend, aerosolize, disperse, disintegrate, or de-gas a solution. A sonicator may be used to disrupt a cell, such as a pathogen cell in a sample. Sample preparation may include exposing pathogen-identifying material by sonication to detect, identify, or measure pathogens. A sonicator may transfer ultrasonic energy to the sample solution by contacting its tip to an exterior wall of a vessel containing the sample. Multipurpose devices including a sonicator also include further components for additional actions and assays. Devices, and systems comprising such devices, may communicate with a laboratory or other devices in a system for sample assay and analysis. Methods utilizing such devices and systems are provided. The improved sample preparation devices, systems and methods are useful for analyzing samples, e.g. for diagnosing patients suffering from infection by pathogens.

Abstract: The present invention provides an aminoalcohol together with, as necessary, at least one selected from the group consisting of: at least one compound selected from the group consisting of urea and a urea derivative; a nonionic detergent; and sucrose to provide a biological material having an excellent light-transmitting property. The present invention provides a technique that allows a high-throughput observation of gene expression/localization or cell morphology in tissue at an whole-tissue level.

Abstract: A one-dimensional linear array of liquid plugs separated by a gas phase is coalesced by (1) pumping the array through a conduit having a flow restriction of sufficient resistance or (2) a rapid and sudden increase in applied pressure (such as by increasing the flow rate). In this way, the flow of material through the conduit is restricted sufficiently to compress the gas phase into (partial or full) solubility within one or more components of the liquid phase.

Abstract: In order to surely discharge dust produced in a sample containing part 10, the present invention is adapted to include: a dust introduction part 30 that has a through-hole 3a formed penetrating in a vertical direction and introduces dust produced in the sample containing part 10 into the through-hole 3a; a dust containing part 43 that contains the dust discharged through the through-hole 3a; and a dust discharge path 41a of which one end is connected to the dust introduction part 30 to communicatively connect to the through-hole 3a and the other end is connected to the dust containing part 43, in which the dust discharge path 41a is linearly formed along the vertical direction from the one end to the other end.

Abstract: The present invention relates to a method for separating multiple biological materials using characteristics of magnetic nanoparticles. The method of the present invention is able to separate multiple biological materials at once due to differences in trajectory in an external magnetic field of the same intensity after attaching magnetic nanoparticles to the biological materials to be separated using differences in magnetic susceptibility or magnetization depending on compositions of the magnetic nanoparticles.

Abstract: The present invention provides a novel method of in vitro sample preparation for the analysis of proteins. In a first aspect, the present invention is a method comprising the separation and individual treatment of blood platelets and platelet-poor plasma obtained from a platelet-rich plasma sample. This allows for optimal treatment of both fractions and overcomes many of the problems associated with current methods. In a second aspect of the present invention the platelet sample preparation method can be implemented before a biochip based immunoassay for the detection of platelet proteins in combination with plasma proteins.

Abstract: A conduit includes at least one tag having a known location, or a plurality of tags having different longitudinal or radial locations or depths, wherein each tag is responsive to a reader to uniquely identify itself. A wear monitoring method and system includes a tag reader and a processor which executes instructions to compare the presence of each tag identified by the reader with a list of all tags initially present in the conduit.

Abstract: A rotational rheometer for measuring powdery or granular materials has a measuring container for receiving the product to be measured and a cover for the measuring container. A measuring body is held by a measuring shaft. The measuring body and the container are rotatable relative to one another. The measuring shaft is guided through the cover with low friction, or without contact altogether. An evaluation unit is arranged outside the measurement container to evaluate the measured values received by the measuring shaft. To seal the bearing gap or the passage of the measuring shaft in or through the cover in the measuring container, both a fluid seal with a sealing fluid inlet and at least a geometric seal cooperating with the fluid seal are provided as a powder barrier.

Abstract: A unit for measuring the falling speed of particles in suspension in a fluid comprises a sealed container having an open compartment containing fluid, and a sealed compartment, and, in the sealed compartment, at least three electromagnetic radiation emitters distributed along a longitudinal axis of the open compartment and oriented according to a radiation axis crossing the open compartment at different heights along the longitudinal axis, an equal number of receivers distributed along the longitudinal axis, each receiver placed in the radiation axis of a corresponding emitter, and a system for acquiring data connected to the receivers which is used to obtain the falling speed of the particles and the change of same as a function of the height in the open compartment and as a function of time, said change quantifying the flocculation of the particles.

Abstract: A cell for measuring the permeation of a target gas through a sample includes upstream and downstream chambers connected by an opening, a primary seal in contact with the bottom of the upstream chamber and surrounding the opening, and a removable sample holder and means for assembling the sample holder in the cell. Upper and lower frames included in the sample holder are each provided with a through opening. The sample holder includes means for assembling the sample in the sample holder and a first seal flush with the front surface of the lower frame, and surrounding the through opening of the lower frame. In the lower frame of the sample holder, a second seal is flush with the front surface of the lower frame, surrounding the through opening of the lower frame, and being surrounded with the first seal, and a second channel emerging between the two secondary seals.

Abstract: A system and method for a flow cytometer system including a prepared sample fluid with reference beads; an interrogation zone that analyzes the prepared sample fluid; a peristaltic pump system that draws the sample fluid through the interrogation zone; and a processor that monitors a measured volume of sample fluid sampled by the peristaltic pump system and an expected sample volume based on data generated by the analysis of the sample fluid. A system and method is additionally described using an alternative volume sensing fluidic system.

Abstract: A device for separating a sample of cells suspended in a bio-compatible ferrofluid is described, The device includes a microfluidic channel having a sample inlet, at least one outlet and a length between the same inlet and the at least one outlet, wherein a sample can be added to the sample inlet and flow along the microfluidic channel length to the at least one outlet. The device includes a plurality of electrodes and a power source for applying a current to the plurality of electrodes to create a magnetic field pattern along the microfluidic channel length. The present invention also includes a method of using said device for separating at least one cell type.

Abstract: [Object] To provide a particle sorting apparatus, a particle sorting method, and a program that are capable of efficiently sorting particles even when sizes of particles to be sorted are not uniform. [Solving Means] A particle sorting apparatus includes a charge section that imparts charges to at least a part of droplets discharged from an orifice from which a fluid stream is generated, and a charge control section that adjusts a charge amount to be imparted to the droplets by the charge section. Further, the charge control section is structured to adjust the charge amount according to sizes of particles included in the droplets.

Abstract: A method is presented by which means small particles in solution, of various structures and of sizes up to several hundred nanometers, may be measured by light scattering means. An inventive technique is described, permitting the traditional Rayleigh-Gans approximation to be extended, allowing thereby measurement of the mean square radii of particles over a greater size range. Such determinations obviate the need to fit the collected data to a particular closed form model of which, in any event, only a few exist. The new method is particularly important for determining structural features of irregular particles whose scattering depends on their orientation with respect to the direction of the incident illumination.

Abstract: A flow cytometry system having a flow channel defined through the thickness of a substrate is disclosed. Fluid flowing through the flow channel is illuminated by a first plurality of surface waveguides that are arranged around the flow channel in a first plane, while a second plurality of surface waveguides arranged around the flow channel in a second plane receive light after it has interacted with the fluid. The illumination pattern provided to the fluid is controlled by controlling the phase of the light in the first plurality of surface waveguides. As a result, the fluid is illuminated with light that is uniform and has a low coefficient of variation, improving the ability to distinguish and quantify characteristics of the fluid, such as cell count, DNA content, and the like.

Abstract: Techniques for determining mudcake properties include positioning a member of a test apparatus into a prepared mudcake sample at a specified depth of the mudcake sample, the mudcake sample associated with a drilling fluid and including a specified thickness; detecting, with the test apparatus, a force exerted on the member relative to a displacement distance of the member from the specified depth in the mudcake sample during removal of the member from the mudcake sample; recording, with the test apparatus, the detected force relative to the displacement distance; and determining, with the test apparatus, one or more properties of the mudcake sample based on the recorded force relative to the displacement distance.

Abstract: An isotope ratio of a continuous sample is measured in an isotope ratio spectrometer. At least one sample isotope ratio is measured over a measurement time period tns, (n?1) and a sample concentration cns is measured over at least a part of the measurement time period cns. A reference gas concentration cnref for the spectrometer is selected for reference to the sample measured during the measurement time period tns, on the basis of the measured sample concentration cnref. An isotope ratio of the reference gas is measured at the selected reference gas concentration cnref in the spectrometer. The at least one isotope ratio of the sample measured during the measurement time period tnref is calibrated using the measured isotope ratio of the reference gas at the corresponding reference gas concentration cnref and a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements are determined, each being for a different time.

Abstract: A photometer is provided for measuring the concentration of a chromophore in a fluid. The photometer includes a light source, a sample cell and a detector. The light source includes first, second, third and fourth light emitting diodes (LEDs). Each of the first and second LEDs emit light at a measurement wavelength and each of the third and fourth LEDs emit light at a reference wavelength. The first and second LEDs are arranged diagonal to each other and the third and fourth LEDs are arranged diagonal to each other. The photometer performs a routine for correcting concentration measurement for LED drift.

Abstract: An optical computing device utilizes an Integrated Computational Element (“ICE”) core to correct calibration transfer errors in the device.

Abstract: A laser spectrometer can be operated for analysis of one or more analytes present in a combustible gas mixture. The spectrometer can include one or more features that enable intrinsically safe operation. In other words, electrical, electronic, thermal, and/or optical energy sources can be limited within an hazardous are of the spectrometer where it is possible for an explosive gas mixture to exist. Methods, systems, articles and the like are described.

Abstract: MIR spectroscopy systems comprising hierarchical spectral dispersion that enables fine spectral resolution and high sensitivity spectroscopy are disclosed. Hierarchical spectral dispersion is derived by employing at least two diffractive lens arrays, located on either side of a test sample, each receiving input radiation having an input spectral range and distributing the input radiation into a plurality of output signals, each having a fraction of the spectral range of the input radiation. As a result, the signal multiplication factor of the two arrays is multiplied in a manner that mitigates the propagation of wavelength harmonics through the system. In some embodiments, an emitter array comprising a plurality of spectrally selective emitters provides the input MIR radiation to a spectroscopy system. In some embodiments, spectrally selective detectors are used to detect narrow spectral components in the radiation after they have passed through the test sample.

Abstract: One disclosed optical computing device includes a sampling window arranged on a housing, an electromagnetic radiation source configured to emit electromagnetic radiation, the electromagnetic radiation being configured to optically interact with a substance outside of the sampling window, at least one integrated computational element (ICE) core arranged to optically interact with the electromagnetic radiation, and a detector arranged to receive the electromagnetic radiation following its optical interaction with the substance and the at least one ICE core and generate an output signal corresponding to a characteristic of the substance, wherein the electromagnetic radiation impinges upon the surfaces of the sampling window at an angle of incidence from normal to the sampling window, and wherein specular reflected light reflects off the sampling window at an opposing angle of incidence, the specular reflected light emanating away from the sampling window such that it is not detected by the detector.

Abstract: A method detects whether or not a workpiece is coated with a water-soluble protective film. The method includes a preparatory step before detection and a detecting step. The preparatory step includes irradiating with infrared light a first region coated with the water-soluble protective film and a second region not coated with the water-soluble protective film for a reference, receiving the reflected light, and thereby acquiring an intensity of reflection from the first region and an intensity of reflection from the second region; and a threshold determining step of determining a threshold from the intensity of reflection from the first region and the intensity of reflection from the second region at a wavenumber of 3000 cm?1 to 3600 cm?1. The detecting step includes irradiating a surface of the workpiece with the infrared light, receiving the reflected light, and comparing the thus obtained intensity of reflection with the threshold.

Abstract: Disclosed is a surface plasmon resonance sensor chip, comprising a glass substrate layer, a gold film layer and a probe molecule layer. The gold film layer is disposed on the glass substrate layer and the probe molecule layer is disposed on the gold film layer. Also disclosed is a method for preparing the surface plasmon resonance sensor chip. By means of a surface plasmon resonance spectrum generated by the surface of the gold film disposed on the glass substrate, the content of lipopolysaccharide in an aqueous solution is detected in a fast, simple, quantitative and ultra-sensitive way.

Abstract: An optical element includes a main body formed of a light transmissive material and including an arc-shaped optical path, and a gap formed on the arc-shaped optical path in the main body. The gap may have a notch shape. The main body may have a semicircular plate shape. The main body may have a hemispherical shape.

Abstract: An optical measuring apparatus and method for analysis of samples contained in liquid drops provided by a liquid handling system has a liquid handling tip. A light source irradiates the liquid drop; a detector measures sample light; and an optics system with first optical elements transmits irradiation light, and a processor processes the measurement signals. The liquid drop is suspended at the liquid handling orifice of the liquid handling tip in a position where the liquid drop is penetrated by a first optical axis defined by the light source and the first optical elements. The liquid drop is physically touched only by the liquid handling tip and the liquid sample inside the liquid handling tip. A mutual adaption of the size and position of the liquid drop with respect to the first optical elements is achieved.

Abstract: The invention encompasses analyzers and analyzer systems that include a single molecule analyzer, methods of using the analyzer and analyzer systems to analyze samples, either for single molecules or for molecular complexes. The single molecule uses electromagnetic radiation that is translated through the sample to detect the presence or absence of a single molecule. The single molecule analyzer provided herein is useful for diagnostics because the analyzer detects single molecules with zero carryover between samples.

Abstract: Compositions and methods for increasing fluorescent signals generated by biomarkers are described. This serves to increase the accuracy of results when the biomarkers are used for the detection and diagnosis of physiological conditions, such as organ function and plasma volume.

Abstract: A modular device for remote chemical material analysis with a basic function unit which is formed with a transport module, which is partly equipped with a mobile frame construction which is set up with at least a power supply of the laser, a detection system, designed for plasma radiation dispersion according to the wavelength and its record, a control and evaluation block in the form of PC and a control electronic block and partly is connected with a laser module which contains a laser head, which serves as a source of laser pulses, where the essence of the invention is that the laser module is equipped with a laser beam router of optional routing of laser pulses either into a stand-off module when analyzed with a “Stand-Off LIBS” method or into a fiber module when analyzed with a “Remote LIBS” method.

Abstract: An optochemical sensor comprises a measuring element excitable by the light of an excitation light source and in contact with a medium to be measured, and a measuring arrangement including at least one excitation light source and a detector as well as a hood separating the measuring arrangement from the measuring element, wherein the excitation light source and the detector are fixed to a base plate arranged in parallel with the measuring element, the hood, the excitation light source and the detector are separated from one another by at least a portion of the material thickness of the hood, and light from the excitation light source through an optical waveguide impinges on the measuring element at such an angle that fluorescence light emitted by the measuring element impinges perpendicularly on the detector.

Abstract: The present invention provides near-infrared fluorogenic and/or chromogenic formulations, methods, systems and kits. Upon contacting an azine with an oxidant and a peroxidase, the azine is converted to an azine derivative which is both visibly colored and fluorescent. This invention also provides high sensitive methods to detect biological molecules, showing better sensitivity than chemiluminescence methods. Advantageously, the formulation and reaction is free of luminol or luminol derivatives.

Abstract: A defect inspection system is provided for inspection of defects in the surface of a sample. An array of light sources is used, with different light sources providing light to the sample from different directions. A main direction of illumination is defined with highest intensity, and this direction evolves over time. By providing varying directional illumination instead of blanket illumination, it becomes easier to detect defects.

Abstract: In an optical inspection tool, an illumination aperture is opened at each of a plurality of aperture positions of an illumination pupil area one at a time across the illumination pupil area. For each aperture opening position, an incident beam is directed towards the illumination pupil area so as to selectively pass a corresponding ray bundle of the illumination beam at a corresponding set of one or more incident angles towards the sample and an output beam, which is emitted from the sample in response to the corresponding ray bundle of the incident beam impinging on the sample at the corresponding set of one or more incident angles, is detected. A defect detection characteristic for each aperture position is determined based on the output beam detected for each aperture position. An optimum aperture configuration is determined based on the determined defect detection characteristic for each aperture position.