Abstract: A method of detecting the presence of bacterial spores in a sample comprises non-destructively to the spores carrying out the steps of assessing the absorption, reflectance, and/or index of refraction (IOR) of the sample, subjecting the sample to UV radiation, and reassessing the absorption, reflectance, and/or index of refraction (IOR) of the sample to determine the presence or absence of spores. A detector is also disclosed.

Abstract: A laser scanner, in particular a safety laser scanner, in accordance with the operating principle of the time of flight process, comprising a light transmission unit having at least one light transmitter for transmitting a polarized transmitted light beam into a monitored zone; a light reception unit having at least one light receiver for detecting the polarization component of the light reflected in the monitored zone being orthogonal to the polarization direction of the transmitted light beam, and/or the polarization component of the light reflected in the monitored zone being parallel to the polarization direction of the transmitted light beam, and for generating a received signal corresponding to the detected orthogonal polarization component and/or the detected parallel polarization component; and an evaluation unit configured to evaluate the time development of the detected orthogonal polarization component and/or of the detected parallel polarization component.

Abstract: The present invention relates to ellipsometer and polarimeter systems, and more particularly is an ellipsometer or polarimeter or the like system which operates in a frequency range between 300 GHz or lower and extending to higher than at least 1 Tera-hertz (THz), and preferably through the Infra-red (IR) range up to, and higher than 100 THz, including: a source such as a backward wave oscillator; a Smith-Purcell cell; a free electron laser, or an FTIR source and a solid state device; and a detector such as a Golay cell; a bolometer or a solid state detector; and preferably including a polarization state generator comprising: an odd bounce image rotating system and a polarizer, or two polarizers; and optionally including least one compensator and/or modulator, in addition to an analyzer.

Abstract: Provided is a multi-channel surface plasmon resonance sensor using beam profile ellipsometry; and, more particularly, to a high sensitive measuring technology, which is coupled with a vertical illumination type focused-beam ellipsometer using a multi-incident angle measurement method, and a surface plasmon resonance (SPR) sensing part deposited with a metal thin film. The multi-channel surface plasmon resonance sensor includes a vertical illumination type focused-beam ellipsometer, in which light is polarized; a surface plasmon resonance (SPR) sensing part which is provided at the objective lens part of the focused-beam ellipsometer so as to generate SPR according to an angle change of the polarized light; and a flow unit which supplies a buffer solution containing a bio material binding to or dissociation from the metal thin film generating surface plasmon, wherein the SPR and the ellipsometric phase change by change in an angle and a wavelength are simultaneously detected.

Abstract: Provided is a multi-channel surface plasmon resonance sensor using beam profile ellipsometry; and, more particularly, to a high sensitive measuring technology, which is coupled with a vertical illumination type focused-beam ellipsometer using a multi-incident angle measurement method, and a surface plasmon resonance (SPR) sensing part deposited with a metal thin film. The multi-channel surface plasmon resonance sensor includes a vertical illumination type focused-beam ellipsometer in which light is polarized; a surface plasmon resonance (SPR) sensing part which is provided at the objective lens part of the focused-beam ellipsometer; and a multi-channel flow unit which supplies a buffer solution containing a bio material binding to or dissociation from a metal thin film generating surface plasmon.

Abstract: In an evaluation device, an analyzer is rotated so that the azimuth of the transmission axis of the analyzer has an inclination angle of 90 degrees±3 degrees with respect to the transmission axis of a polarizer. An imaging camera captures a regularly reflected image of a wafer under each condition, and an image processing unit evaluates the shape of a repeating pattern and detects dose defects and focus defects on the basis of the two images of the wafer captured by the imaging camera.

Abstract: A detector for detecting a birefringent object near a skin surface of a human body part or an animal body part includes a source for emitting optical radiation having first and second wavelengths and an incident polarization state. An imaging unit is configured to image the birefringent object near the surface includes a detection unit for detecting optical radiation scattered and/or reflected by the birefringent object and/or the surface at the first and second wavelengths. A control unit is configured to process a signal from the detection unit for discrimination between the birefringent object and the surface. The detection unit is configured to detect scattered and/or reflected optical radiation coming from the birefringent object and/or the surface, having a first polarization state corresponding to the incident polarization state and a second polarization state being different from the first polarization state.

Abstract: A system for monitoring thin-film fabrication processes is herein disclosed. Diffraction of incident light is measured and the results are compared to a predictive model based on at least one idealized or nominal structure. The model and/or the measurement of diffracted incident light may be modified using the output of one or more additional metrology systems.

Abstract: Provided herein is an apparatus, including an optical characterization device; a photon detector array configured to sequentially receive a first set of photons scattered from surface features of an article and a second set of photons scattered from surface features of the article and subsequently processed by the optical characterization device; and a chemical characterization means for chemically characterizing the surface features of the article, wherein the chemical characterization means is configured for processing the first set of photons received by the photon detector array and the second set of photons received by the photon detector array.

Abstract: An ellipsometer includes an integrated focusing system with a beam splitter between the sample and the ellipsometer detector. The beam splitter provides a portion of the radiation to a lens system that magnifies any deviation from a best focus position by at least 2×. The focusing system includes a 2D sensor, where the spot of light focused on the sensor is 50 percent or smaller than the sensor. The focusing system may further include a compensator to correct optical aberrations caused by the beam splitter. A processor receives an image signal and finds the location of the spot from which focus error can be determined and used to correct the focal position of the ellipsometer. The processor compensates for movement of the spot caused by rotating optics. Additionally, a proportional-integral-derivative controller may be used to control exposure time and/or gain of the camera.

Abstract: A system is configured to measure two separately polarized beams upon diffraction from a substrate in order to determine properties of a grating on a substrate. Linearly polarized light sources are passed via a fixed phase retarder in order to change the phase of one of two orthogonally polarized radiation beams with respect to the other of the two beams. The relative phases of the two radiation beams and other features of the beams as measured in a detector gives rise to properties of the substrate surface. The grating and the initial linear polarization of the radiation beam are angled non-orthogonally relative to each other.

Abstract: Through silicon imaging and probing. A light source provides unpolarized light to be projected on a device under test (DUT). Light reflected from the DUT may be captured by a camera or other image capture device. A pellicle is utilized to reflect light from the light source toward the DUT. The pellicle also passes light reflected by the DUT to the camera. One or more linear polarizers or half wave plates may be used to provide the desired light polarization. The ability to provide the desired polarization provides an improved image that can be captured by the camera.

Abstract: Optical detection of molecules using a biochip having at least one reagent immobilizing area designed to receive one or more reagents and at least one calibration structure with a predetermined height to provide a height reference for optical measurement is disclosed. When the calibration structure is illuminated by a probe beam of light, a first reflected beam of light is reflected off the calibration structure, and a second reflected beam of light is reflected off the reagent immobilizing area. The first reflected beam and the second reflected beam are compared to determine a height at the reagent immobilizing area.

Abstract: An apparatus for inspecting a measurement object, comprising a workpiece support for receiving the measurement object and a measuring head carrying an optical sensor. The measuring head and workpiece support are movable relative to one another. The optical sensor has an objective and a camera for capturing an image of the measurement object. The objective has a light entrance opening and a light exit opening, a diaphragm, and a multitude of lens-element groups arranged in the objective between the light entrance opening and the light exit opening one behind another along a longitudinal axis of the objective. At least two lens-element groups are displaceable parallel to the longitudinal axis. An illumination device illuminates the measurement object at a triangulation angle relative to the longitudinal axis, and a sensor device detects radiation from the illumination device that is incident on the sensor device through the objective.

Abstract: A method and system are presented for use in characterizing properties of an article having a structure comprising a multiplicity of sites comprising different periodic patterns, where method includes providing a theoretical model of prediction indicative of optical properties of different stacks defined by geometrical and material parameters of corresponding sites, said sites being common in at least one of geometrical parameter and material parameter; performing optical measurements on at least two different stacks of the article and generating optical measured data indicative of the geometrical parameters and material composition parameters for each of the measured stacks; processing the optical measured data, said processing comprising simultaneously fitting said optical measured data for the multiple measured stacks with said theoretical model and extracting said at least one common parameter, thereby enabling to characterize the properties of the multi-layer structure within the single article.

Abstract: A method for optically inspecting a specimen by directing a probe beam onto the specimen at varying angle of incidence and azimuth angle, thereby producing a reflected probe beam, gathering the reflected probe beam, separating the reflected probe beam as a function of wavelength, adding astigmatism to separate the reflected probe beam as a function of at least one of the angle of incidence and the azimuth angle, and evaluating the specimen based at least on changes in the reflected probe beam as a function of wavelength of the reflected probe beam and at least one of the angle of incidence and the azimuth angle.

Abstract: To provide a surface plasmon sensor for measuring a refractive index by which a refractive index can be easily measured with high accuracy without relying on an absorption curve. The surface plasmon sensor includes: a reflection plate which includes a metal layer having a periodic structure and on which a specimen is arranged; a light source which irradiates an incident light to the reflection plate; a light receiving part which receives a reflected light reflected on the reflection plate; and a measurement part which measures a refractive index of the specimen based on phase information on two kinds of waves which are included in reflected light reflected on a periodic structure surface and differ in polarization direction.

Abstract: Provided are a defect inspecting method and a defect inspecting apparatus, wherein defect detecting sensitivity is improved and also haze measurement is performed using polarization detection, while suppressing damages to samples. The defect inspecting apparatus is provided with a light source which oscillates to a sample a laser beam having a wavelength band wherein a small energy is absorbed, and two independent detecting optical systems, i.e., a defect detecting optical system which detects defect scattered light generated by a defect, by radiating the laser beams oscillated by the light source, and a haze detecting optical system which detects roughness scattered light generated due to roughness of the wafer surface. Polarization detection is independently performed with respect to the scattered light detected by the two detecting optical systems, and based on the two different detection signals, defect determination and haze measurement are performed.

Abstract: The embodiments of the invention relate to a method for determining at least one characteristic of a physical resource for use in a physical resource consuming apparatus.

Abstract: An apparatus and method for providing image contrast enhancement is disclosed. A mobile object is equipped with a laser source, polarization filter, and imaging apparatus. The reflection of the laser source output passes through the filter and is received by the imaging apparatus. If the output of the laser source impinges a metallic marker plate located at a pre-determined location, the filter decreases the intensity level of image components not associated with the reflection of the laser source output. The imaging apparatus uses such filtered image components to determine the position and/or orientation of the mobile object.

Abstract: A method and system are presented for determining a line profile in a patterned structure, aimed at controlling a process of manufacture of the structure. The patterned structure comprises a plurality of different layers, the pattern in the structure being formed by patterned regions and un-patterned regions. At least first and second measurements are carried out, each utilizing illumination of the structure with a broad wavelengths band of incident light directed on the structure at a certain angle of incidence, detection of spectral characteristics of light returned from the structure, and generation of measured data representative thereof. The measured data obtained with the first measurement is analyzed, and at least one parameter of the structure is thereby determined.

Abstract: Systems and methods for inspecting a wafer are provided. One system includes an illumination subsystem configured to illuminate the wafer; a collection subsystem configured to collect light scattered from the wafer and to preserve the polarization of the scattered light; an optical element configured to separate the scattered light collected in different segments of the collection numerical aperture of the collection subsystem, where the optical element is positioned at a Fourier plane or a conjugate of the Fourier plane of the collection subsystem; a polarizing element configured to separate the scattered light in one of the different segments into different portions of the scattered light based on polarization; and a detector configured to detect one of the different. portions of the scattered light and to generate output responsive to the detected light, which is used to detect defects on the wafer.

Abstract: The present invention provides an inspection apparatus having a high throughput and high sensitivity with respect to a number of various manufacturing processes and defects of interest in inspection of a specimen such as a semiconductor wafer on which a pattern is formed. The apparatus illuminates with light the specimen having the pattern formed thereon, forms an image of the specimen on an image sensor through a reflective optics, and determines the existence/nonexistence of a defect. The reflective optics has a conjugate pair of Fourier transform optics. An aberration of the reflective optics is corrected off-axis. The reflective optics has a field of view in non-straight-line slit form on the specimen surface. Also, the optics is of a reflection type, includes a conjugate pair of Fourier transform optics and has a field of view in non-straight-line slit form. An optimum wavelength band is selected according to the specimen (FIG. 1).

Abstract: An orientation tracking system for a moving platform includes a transmitter which generates an beam having a known polarization with respect to a predefined coordinate system. The moving platform includes an ellipsometric detector capable of detecting the polarized beam when within the line-of-sight of the transmitter, and measuring its polarization state. The polarization state indicates the rotational orientation of the moving platform with respect to the predefined coordinate system. The beam could also be used to convey guidance commands to the platform.

Abstract: A sensor and method for determining the optical properties of a sample material is disclosed. The sensor comprises a light source that generates a linearly polarized light beam having a predetermined polarization orientation with respect to the plane of incidence. The linearly polarized light beam is reflected off the sample and is split into second and third light beams where the second and third light beam consist of the combined projections of mutually orthogonal components of the first light beam. A signal processor measures the intensity difference between the second and third light beams to calculate the phase difference induced by the sample material.

Abstract: Methods and systems for small angle CD metrology with a small spot size are introduced to increase measurement sensitivity while maintaining adequate throughput necessary for modern semiconductor manufacture. A small angle CD metrology system includes a small angle spectroscopic ellipsometry (SE) subsystem combined with a small angle spectroscopic reflectometry system, both operated at small angles of incidence. The small angle SE subsystem is configured to operate in a complete Mueller Matrix mode to further improve measurement sensitivity. The small angle CD metrology system includes an objective having all reflective surfaces in the light path. In some embodiments, the all-reflective objective is a Schwartzschild objective having an axicon mirror element to further reduce measurement spot size. In some embodiments, the small angle CD metrology system includes a dynamic aperture subsystem to isolate specific ranges of angles of incidence and azimuth for improved measurement sensitivity.

Abstract: Light from a light source device (4) is polarized through a polarizer (5) and is caused to impinge obliquely on an object (W) to be inspected. The resulting scattered light (SB) is received by a CCD imaging device (7) having an element (9) for separating scattered light disposed in a dark field. Component light intensities are worked out for an obtained P-polarized component image and an obtained S-polarized component image and a polarization direction is determined as a ratio of them. The component light intensities and the polarization directions are determined from images obtained by imaging of the light scattering entities in a state where stress is applied to the object to be inspected and in a state where stress is not applied thereto. The component light intensities and the polarization directions are compared with predetermined threshold values.

Abstract: A defect inspecting apparatus inspects defects of a sample having a pattern formed on the surface. The defect inspecting apparatus is provided with a stage which has a sample placed thereon and linearly moves and turns; a light source; an illuminating optical system, which selects a discretionary wavelength region from the light source and epi-illuminates the sample surface through a polarizer and an objective lens; a detecting optical system, which obtains a pupil image, by passing through reflection light applied by the illuminating optical system from the surface of the sample through the objective lens and an analyzer which satisfies the cross-nichols conditions with the polarizer; and a detecting section which detects defects of the sample by comparing the obtained pupil image with a previously stored pupil image. Conformity of the pattern on a substrate to be inspected can be judged in a short time.

Abstract: Methodology for determining uncertainty in a data set which characterizes a sample involving elimination of the influence of sample alteration drift caused by data set acquisition, and/or elimination of the influence of system drift during data acquisition.

Abstract: An optical system is presented for use in measuring in patterned structures having vias. The system is configured and operable to enable measurement of a via profile parameters. The system comprises an illumination channel for propagating illuminated light onto the structure being measured, a detection channel for collecting light returned from the illuminated structure to a detection unit, and a modulating assembly configured and operable for implementing a dark-field detection mode by carrying out at least one of the following: affecting at least one parameter of light propagating along at least one of the illumination and detection channels, and affecting propagation of light along at least the detection channel.

Abstract: A system and method for detection of a target object/material includes identifying a polarimetric signal for a plurality of aspect angles. One/two-dimensional Mueller matrix image or one/two-dimensional Stokes vector image can be processed using power spectral analysis, wavelet and fractal analysis for further image, having increased discrimination with reduced false-ratio. In addition, each of the angular polarization states due to their association with a particular aspect angle are then cross-correlated to generate a two-dimensional image that relates the level of correlation with the aspect angle. Finally, the output information, including statistical parameters are fed to the input of a neural-fuzzy network for further optimization and image enhancement.

Abstract: A system for and method of allowing visual observation of a sample being subject to investigation by an electromagnetic beam, to identify where thereupon a beam of sample investigating electromagnetic radiation is caused to impinge, in combination with a data detector of the beam of sample investigating electromagnetic radiation after it interacts with the sample.

Abstract: An adjustable, composite polarizer can include first and second plate polarizers and an adjusting apparatus. The adjusting apparatus can adjust a pitch angle and a roll angle for the first and second plate polarizers while maintaining a predetermined, minimal distance between those plates. In this configuration, the adjustable, composite polarizer can provide mirror symmetric polarization with respect to an incident plane while providing the flexibility of any polarization.

Abstract: A device for measuring the rotating angle of two objects rotating in relation to each other around an axis includes a light source and a polarizer, whereby the light source and the polarizer rotate in relation to each other as function of the rotating angle. The device also includes a receiver measuring the luminous intensity reflected by the polarizer, to produce a signal dependent on the rotating angle. The receiver has at least one initial reception element and the light emitted by the light source is either polarized or becomes polarized. A polarizing filter with an initial direction of polarization is positioned in front of the first reception element. At least one element casting a shadow is positioned in front of the receiver and the receiver has at least one quadrant diode. The position and/or shape of the shadow are varied on the receiver over a rotation of 360°.

Abstract: System for, and method of ellipsometric investigation of and analysis of samples which have, for instance, a non-random effectively “regular” textured surface, and/or a surface characterized by an irregular array of faceted structures.

Abstract: An optical system configured to visually inspect a target having a variable position with respect to the optical system is provided. The optical system includes a polarizer configured to convert an incident light reflected or diffused from the target into linearly polarized light; a light modulating element configured to modulate a polarization state of the linearly polarized light in response to control signals; and a lens group comprising at least one birefringent element, the birefringent element configured to refract or reflect the modulated linearly polarized light with a first polarization state under a first refraction index to enable inspection of the target at a first object position, and the birefringent element further configured to refract or reflect the modulated linearly polarized light with a second polarization state under a second refraction index to enable inspection of the target at a second object position.

Abstract: The embodiments relate to a method of calculating an image for simulating by calculation an image imaged by a projection optical system. In this method, a Stokes vector showing a characteristic of an illumination light is acquired first. Next, this Stokes vector is divided into a polarized light component vector and a non-polarized light component vector. The polarized light component vector is divided into a first coherent component vector and a first non-coherent component vector. The non-polarized light component vector is divided into a second coherent component vector and a second non-coherent component vector. Then, imaging calculation is performed at least for the first coherent component vector and the second coherent component vector, respectively.

Abstract: An ellipsometer includes an integrated focusing system with a beam splitter between the sample and the ellipsometer detector. The beam splitter provides a portion of the radiation to a lens system that magnifies any deviation from a best focus position by at least 2×. The focusing system includes a 2D sensor, where the spot of light focused on the sensor is 50 percent or smaller than the sensor. The focusing system may further include a compensator to correct optical aberrations caused by the beam splitter. A processor receives an image signal and finds the location of the spot from which focus error can be determined and used to correct the focal position of the ellipsometer. The processor compensates for movement of the spot caused by rotating optics. Additionally, a proportional-integral-derivative controller may be used to control exposure time and/or gain of the camera.

Abstract: A polarimetric measurement device and method with microscopic resolution include a polarization conversion device to modify the polarization of a beam so as to switch from a spatially uniform distribution to a distribution that is cylindrically symmetric about the optical axis, and vice versa. The conversion device is positioned on the axis of a focusing objective for focusing the cylindrically symmetric polarized beam onto the surface of a sample to be measured. The device may be incorporated into a microellipsometer, or an interference contrast microscope, or used as a polarimetric accessory for a microscope.

Abstract: An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent. The radiation that is reflected off the substrate is radially polarized.

Abstract: Disclosed here is a macro inspection apparatus for a sample such as a semiconductor wafer having a pattern formed thereon, the apparatus being capable of detecting abnormalities in dimension and size with high sensitivity. The inspection apparatus for a sample having pattern formed thereon includes: an illumination optical system which illuminates the sample having the pattern formed thereon; a detection optical system which receives scattered light from the pattern; an imaging device which is disposed over a pupil plane of the detection optical system, the imaging device acquiring Fourier images of the pattern; and a processing unit which compares the Fourier images with the Fourier image of the normal pattern to detect an irregularity of the pattern.

Abstract: A dual optical metrology system includes a first metrology device and a second metrology device, each producing light at different oblique angles of incidence on the same spot of a sample from different azimuth angles. The dual optical metrology system further includes a rotating stage or flip mirrors capable of altering the orientation of the light beams so the first and second metrology devices can measure the same spot on the sample at different orientations. Thus, the first and second metrology devices generate first and second sets of optical metrology data, respectively, at a first orientation with respect to the sample. After the sample is rotated, the first and second metrology devices generate third and fourth sets of optical metrology data. The first, second, third, and fourth sets of data can then be used to determine one or more parameters of the sample.

Abstract: A surface position detecting apparatus includes a light projection system that projects a beam from an oblique direction onto a detection target surface, and a light reception system that receives a beam reflected on the detection target surface, said surface position detecting apparatus adapted to detect a surface position of the detection target surface based on an output from the light reception system. At least one of the light projection system and the light reception system includes a total reflection prism member including an internal reflection surface which totally reflects an incident beam. Upon detection of the surface position of the detection target surface, a refractive index of an optical material forming the total reflection prism member and an angle of incidence of the incident beam to the internal reflection surface of the total reflection prism member are set so as to satisfy a predetermined relation.

Abstract: Provided herein are new methods and apparatus for quantitative measurement and analysis of particles, including new apparatus systems to process and detect nanoparticles in suspension. By focusing a laser beam at the center of a reservoir, nanoparticles are concentrated by optical energy, and fluorescent intensity at the focal point of the laser is measured to quantify particle concentration in the reservoir. The techniques may be applied to the analysis of suspensions of nanoparticles, including natural particles (e.g., microorganisms including whole viruses, bacteria, animal cells, and proteins) and synthetic particles (e.g., colloidal latexes, paints, pigments, and metallic or semiconductor nanoparticles) for medical and industrial applications, among others.

Abstract: An optical sensor includes: a light emission module to emit a linearly polarized light beam having a first polarizing direction to a surface of an object in an incident direction inclined relative to a direction of a normal to the surface; a first photodetector module including a first photodetector disposed within a plane of incidence of the surface in an optical path inclined relative to an optical path of a light beam emitted from the light emission module and regularly reflected on the surface; and a second photodetector module including an optical element disposed within the plane of incidence of the surface in an optical path of a diffused reflection light beam from the surface to separate a linearly polarized light beam having a second polarizing direction perpendicular to the first polarizing direction, and a second photodetector to receive the light beam separated by the optical element.

Abstract: An ellipsometer system comprising a small internal volume cell having fluid entry, and exit ports wherein bubble traps are present in a bifurcated fluid pathway continuous with the fluid exit port. There further being present input and output apertures, for entering and exiting electromagnetic radiation, positioned to allow causing a beam of electromagnetic radiation to impinge on a sample substrate at a location thereon at which, during use, fluid contacts; as well as methodology of its use.

Abstract: Asymmetry metrology is performed using at least a portion of Mueller matrix elements, including, e.g., the off-diagonal elements of the Mueller matrix. The Mueller matrix may be generated using, e.g., a spectroscopic or angle resolved ellipsometer that may include a rotating compensator. The Mueller matrix is analyzed by fitting at least a portion of the elements to Mueller matrix elements calculated using a rigorous electromagnetic model of the sample or by fitting the off-diagonal elements to a calibrated linear response. The use of the Mueller matrix elements in the asymmetry measurement permits, e.g., overlay analysis using in-chip devices thereby avoiding the need for special off-chip targets.

Abstract: The present invention relates to a device for optical characterisation of a sample and/or of the material/materials of the same having an illumination unit which is orientated or can be orientated to illuminate with incident light a sample spatial portion into which the sample can be introduced, a detection unit which is orientated or can be orientated to image the sample introduced into the sample spatial portion by receiving light reflected by the sample, and which is configured to detect at least two different, preferably two orthogonal, polarisation components in the reflected light, and an evaluation unit with which, in the imaging data recorded by the detection unit, those imaged surface elements (reflection elements) of the sample can be identified, the reflected, received light of which is based on a reflection of the incident light on the sample, and with which the detected different polarisation components for these reflection elements can be evaluated for optical characterisation.

Abstract: A polarizing device may be used with sample inspection system having one or more collection systems that receive scattered radiation from a region on a sample surface and direct it to a detector. The polarizing device disposed between the collection system(s) and the detector. The polarizing device may include a plurality of polarizing sections. The sections may be characterized by different polarization characteristics. The polarizing device is configured to transmit scattered radiation from defects to the detector and to block noise from background sources that do not share characteristics with scattered radiation from the defects from reaching the detector while maximizing a capture rate for the defects the detector at a less than optimal signal-to-noise ratio.

Abstract: An optical sensor is disclosed. The optical sensor includes an irradiating system which irradiates a linearly polarized light; a first photodetecting system including a first photodetector which is arranged on an optical path of a light which is specularly reflected from a subject; a second photodetecting system including an optical element which is arranged on an optical path of a light which is diffuse reflected from the subject within an incident face in the subject and which separates a linearly polarized component in a second polarizing direction which is orthogonal to a first polarizing direction and a second photodetector which receives a light separated by the optical element, wherein an angle of taking in the light in the first photodetector and an angle of taking in the light in the second photodetector are mutually different.