Abstract: Disclosed herein are systems and methods including polarization sorting metasurface microlens array devices. In certain embodiments, a polarization imaging device is provided. The polarization imaging device includes: a source of image light; a metasurface lenslet array comprising a plurality of repeating metasurface lenslets, where the plurality of repeating metasurface lenslets comprise a plurality of first metasurface lenslets configured to diffract the image light into a first polarization light in a first direction and a second polarization light in a second direction; an image sensor positioned in the optical path of the first polarization light and the second polarization light, and where the image sensor includes a plurality of image sensing units including a first image sensing unit positioned to sense the first polarization light and a second image sensing unit positioned to sense the second polarization light.

Abstract: A single-shot Mueller matrix polarimeter (1700), MMP, comprising: a polarization state generator (1706), PSG, arranged to receive a source optical field (1704) and provide a probe field (1708) having a plurality of spatial portions, each portion having a different polarization state; a polarization state analyser (1718), PSA, arranged to receive a modified probe field (1716) resulting from interaction of the probe field generated by the PSG with a sample under investigation, and further arranged to apply, to each of a corresponding plurality of spatial portions of the modified probe field, a plurality of retardances and a plurality of fast axis orientations; and a detector (1720) arranged to detect an output (1722) of the PSA.

Abstract: Methods for determining a parameter of a particle in a flow stream (e.g., in a particle analyzer of a flow cytometer) from scattered light are described. Methods according to certain embodiments include irradiating a particle in a flow stream with a frequency-modulated beam of laser light modulated at a reference frequency, detecting scattered light from the particle with a photodetector, generating a frequency-encoded data signal from the detected scattered light, synchronizing the frequency-encoded data signal with the reference frequency and determining one or more parameters of the particle based on the synchronized frequency-encoded data signal. Systems and non-transitory computer readable storage medium with instructions for practicing the subject methods are also provided.

Abstract: An optical system for particle size and concentration analysis, includes: at least one laser that produces an illuminating beam; a focusing lens that focuses the illuminating beam on particles that move relative to the illuminating beam at known or pre-defined angles to the illuminating beam through the focal region of the focusing lens; and at least two forward-looking detectors, that detect interactions of particles with the illuminating beam in the focal region of the focusing lens. The focusing lens is a cylindrical lens that forms a focal region that is: (i) narrow in the direction of relative motion between the particles and the illuminating beam, and (ii) wide in a direction perpendicular to a plane defined by an optical axis of the system and the direction of relative motion between the particles and the illuminating beam. Each of the two forward-looking detectors is comprised of two segmented linear arrays of detectors.

Abstract: A reflector arrangement for position determination and/or marking of target points, comprising a retroreflector and a first sensor arrangement, by means of which the orientation measurement radiation passing through the retroreflector is acquirable. The first sensor arrangement comprises a first optical assembly providing a fisheye lens, and a first sensor, wherein the retroreflector and the first sensor arrangement are arranged in such a way that orientation measurement radiation passing through the retroreflector is projectable onto the detection surface of the first sensor by means of the first optical assembly.

Abstract: A spectral measurement device capable of achieving a high level of diffraction efficiency by reducing the polarization sensitivity of the device. Many such embodiments are capable of achieving high diffraction efficiency by fixing the polarization of the incoming light to a fixed polarized state internal to the device, thereby allowing for the full spectrum of light to be captured and measured by the device.

Abstract: A light source system is provided. The light source system is capable of measuring a polarization angle and includes a light source configured to emit an original light beam, and the original light beam has an original polarization angle. The light source system further includes an amplifying module configured to amplify the original light beam and generate a forward beam for hitting a target, and the forward beam has a forward polarization angle that is equal to the original polarization angle. The light source system further includes a polarization measurement unit, and the polarization measurement unit includes a first polarization measurement module configured to receive a first return beam and measure a first polarization angle of the first return beam. The first return beam is reflected from the target.

Abstract: The embodiments implement polarization-based disturbed earth identification. At least one sensor apparatus comprising a plurality of detector elements receives polarized electromagnetic radiation (EMR) in a first waveband from a scene of an area of a surface of the earth and polarized EMR in a second waveband from the scene, the polarized EMR in the first waveband having a first polarization orientation and the polarized EMR in the second waveband having a second polarization orientation. The sensor apparatus outputs sensor information that quantifies EMR received by each detector element of the plurality of detector elements. A computing device processes the sensor information to generate an image or a classification image of the scene based on an amount of polarized EMR received by each detector element, and presents the image on a display device.

Abstract: The disclosure discloses a method of measuring optical parameters of a polarizer and a measuring device. The polarizer includes a compensation film and a PVA layer. The measuring method includes the following steps. In the first state, providing an incident linearly polarized light sequentially to pass through the compensation film and the PVA layer, acquiring a first measurement parameter and a second measurement parameter when the brightness of the light emitted from the polarizer is lowest and is highest. In the second state, providing the incident linearly polarized light sequentially to pass through the PVA layer and the compensation film, acquiring a third measurement parameter and a fourth measurement parameter when the brightness of the light emitted from the polarizer is lowest and is highest; and acquiring optical parameters of the compensation film and/or the PVA layer in the polarizer according to one or more of the above measurement parameters.

Abstract: In step S101, a specimen containing blood plasma and a coagulation activating agent are introduced into a flow channel, with the coagulation activating agent being positioned ahead, in a state in which portions arrayed in series in the extending direction of the flow channel flow in contact with each other. In step S102, in the process in which the coagulation activating agent, the contact region between the coagulation activating agent and the specimen, and the specimen pass through a measurement portion provided midway along the flow channel in the order named, the refractive indices of the coagulation activating agent and the contact region are measured in a time-series manner. In step S103, the blood coagulation ability of the specimen is measured by comparing the first refractive index value which is the refractive index of the coagulation activating agent with the second refractive index value which is the minimum refractive index of the contact region.

Abstract: Systems and methods for performing semiconductor laser annealing using dual loop control are disclosed. The first control loop operates at a first frequency and controls the output of the laser and controls the 1/f laser noise. The second control loop also controls the amount of output power in the laser and operates at second frequency lower than the first frequency. The second control loop measures the thermal emission of the wafer over an area the size of one or more die so that within-die emissivity variations are average out when determining the measured annealing temperature. The measured annealing temperature and an annealing temperature set point are used to generate the control signal for the second control loop.

Abstract: Active components in an optical spectroscopy based sensor are moved to a remote site and the light is guided between the remote site and the sensing site through optical fibers.

Abstract: An apparatus and system for use in determining location of a celestial body are presented. The apparatus comprises: a polarizer comprising an array of polarized light filter cells and a light sensor array. The array of polarized light filter cells comprises at least a first polarization direction and a second polarization direction different from said first polarization direction. And the polarizer thereby produces polarized light of at least first and second different polarizations. The light sensor array is configured to receive the polarized light from the polarizer and produce data indicative of a pattern of at least one of light polarization intensity and direction. The pattern is indicative of at least one of azimuth and elevation of the celestial body to be located.

Abstract: A single-shot real-time spectropolarimeter for use in astronomy and other sciences that captures and encodes some or all of the Stokes polarization parameters simultaneously using only static, robust optical components with no moving parts is described. The polarization information is encoded onto the spectrograph at each wavelength along the spatial dimension of the 2D output data array. The varying embodiments of the concept include both a two-Stokes implementation (in which any two of the three Stokes polarization parameters are measured) and a full Stokes implementation (in which all three of the Stokes polarization parameters are measured), each of which is provided in either single beam or dual beam forms.

Abstract: Described herein are systems, devices, and methods facilitating optical characterization of scattering samples. A polarized optical beam can be directed to pass through a sample to be tested. The optical beam exiting the sample can then be analyzed to determine its degree of polarization, from which other properties of the sample can be determined. In some cases, an apparatus can include a source of an optical beam, an input polarizer, a sample, an output polarizer, and a photodetector. In some cases, a signal from a photodetector can be processed through attenuation, variable offset, and variable gain.

Abstract: Optical measurement methods are described that are suitable for determining the relaxation behavior of nanoparticles dispersed in a solution. The particles have optically anisotropic properties and are alignable by an external stimulus, for example, an electric or magnetic field. In this manner the optical detection of certain molecules that can bind specifically to the surface of the nanoparticles and thus change the relaxation behavior of the nanoparticles as well as to provide devices for carrying out the methods is possible.

Abstract: An in-line polarization extinction ratio (PER) monitor that generates a value of an optical signal's PER from a single measurement, without requiring the optical transmission signal path of the system to be directly coupled into a separate measurement device. The polarization extinction ratio may be defined as: 10 log(PEx/PEy), where PEx is the power of the optical signal propagating along the “x axis” and PEy is the power propagating along the orthogonal “y axis” (with the z-axis defined as a longitudinal optical axis of the system and the x-y plane orthogonal to this direction of propagation). The PER monitor comprises a section of optical fiber (preferably birefringent or with induced birefringency), with a pair of gratings formed along the fiber and oriented to out-couple orthogonal components of the propagating signal. Photodetectors are used to convert the scattered light into electrical signal equivalents and then processed to yield the PER value.

Abstract: An optical apparatus has a light detecting section which detects light and emits transmitted light where linearly polarized light, which is converted by a polarizing section, is transmitted through a subject. In addition, the optical apparatus has an orthogonal separating section which orthogonally separates the emitted light from the light detecting section and a light reception section which receives light which is orthogonally separated by the orthogonal separating section. A calculation apparatus outputs a rotation control signal to a rotation apparatus and rotation controls the light detecting section so that the rotation plane is orthogonal with regard to an optical path of the transmitted light. Then, the calculation apparatus measures the polarization state of the transmitted light, which is transmitted through the subject S using the intensity with which the light, is received by the light receiving section.

Abstract: A system and method for polarimetry are disclosed in which a polarimeter may include a light source for transmitting a light beam through a sample within a container; a wavelength selector configured to specify a target wavelength at which the polarization rotation of the light beam emerging from the sample will be evaluated; a polarization rotator configured to be selectively moved into and out of a path of the light beam from the light source; and a detector for obtaining a first measurement of the light beam polarization rotation with the polarization rotator outside the path of the light beam, and a second measurement of the light beam polarization rotation with the polarization rotator within the path of the light beam, with both measurements occurring at the wavelength resulting from the configuration of the wavelength selector.

Abstract: Disclosed is a normal-incidence broadband spectroscopic polarimeter containing reference beam, comprising a light source, a first reflecting unit, a first concentrating unit, a second concentrating unit, a polarizer, a first curved mirror, a first planar mirror, a second reflecting unit and a probing unit. Also disclosed is an optical measurement system, comprising the normal-incidence broadband spectroscopic polarimeter containing reference beam. The normal-incidence broadband spectroscopic polarimeter containing reference beam achieves an integral combination of the light beams after splitting, can maintain the polarization state of the light beams while increasing the light transmission efficiency, and has a low complexity.

Abstract: A polarimeter is proposed that utilizes additional Stokes parameter measurements to determine both an average Stokes vector, as well as any rotation of the state of polarization around the Stokes vector. The optical polarimeter is configured to measure the state of polarization (SOP) under multiple, different conditions that yield both averaged Stokes vector and at least one other secondary (filtered) Stokes vector, the latter thus being determined from a subset of the conditions used to create the average Stokes vector. The secondary Stokes vector created from a filtered input will necessarily exhibit changes over time as a function of polarization transformations (based on filter-dependent changes), while the average Stokes vector will retain a constant value. Thus, a comparison of the average Stokes vector to the changing secondary Stokes vector allows for these polarization-dependent transformations to be recognized.

Abstract: A method for imaging skin includes illuminating a subject with at least one light source of one or more light sources. The method includes acquiring a first image of the subject in a first polarization with a respective photodetector of one or more photodetectors configured to acquire images of the subject as illuminated by the at least one light source, and acquiring a second image of the subject in a second polarization with the respective photodetector. The method also includes generating a subtraction image by subtracting at least a portion of the first image from a corresponding portion of the second image, and providing at least a portion of the subtraction image for display.

Abstract: An in-line polarization extinction ratio (PER) monitor that generates a value of an optical signal's PER from a single measurement, without requiring the optical transmission signal path of the system to be directly coupled into a separate measurement device. The polarization extinction ratio may be defined as: 10 log(PEx/PEy), where PEx is the power of the optical signal propagating along the “x axis” and PEy is the power propagating along the orthogonal “y axis” (with the z-axis defined as a longitudinal optical axis of the system and the x-y plane orthogonal to this direction of propagation). The PER monitor comprises a section of optical fiber (preferably birefringent or with induced birefringency), with a pair of gratings formed along the fiber and oriented to out-couple orthogonal components of the propagating signal. Photodetectors are used to convert the scattered light into electrical signal equivalents and then processed to yield the PER value.

Abstract: A depolarizer includes a pair of wedge-shaped plates made of an optically isotropic material, laid one on top of another such that the total thickness is constant and wedge-plate holding means for holding the pair of wedge plates separately. The wedge-plate holding means includes a pressure-applying section for applying pressure to each of the pair of wedge plates in a direction perpendicular to the thickness direction of the pair of wedge plates. The pressure-applying direction for one of the pair of wedge plates and the pressure-applying direction for the other of the pair of wedge plates intersect at an angle of 45 degrees.

Abstract: The invention relates to a method and to a device for determining a piece of polarisation information on a measurement point of a target sample, the device comprising: —a light source capable of emitting a rectilinearly polarised light beam in a predefined direction, the light beam being intended to be reflected by the measurement point of the target sample; —a unit for computing the piece of polarisation information on the measurement point using the beam reflected by the target sample; -a waveguide for guiding the incident beam towards the target sample and the reflected beam towards the computing means; and —a unit for rotating the polarisation, capable of rotating two orthogonal polarimetric components of the incident beam exiting the waveguide and two orthogonal polarimetric components of the reflected beam before passing through the waveguide.

Abstract: The invention provides spectroscopy apparatuses and methods allowing precise overlapping between circularly polarized pump beam and a counter propagating linearly polarized probe beams in a sample which presents unique advantages for precision spectroscopy. In general, the apparatus comprises a phase retarding element with which by double pass by retro reflection of an incident beam turn linearly polarized light to circular and vice versa. This unique configuration enable to design a compact and miniature apparatus which may be applied for measuring polarization spectroscopy, nonlinear optical rotation and coherent population trapping phenomena with certain advantages resulting from the unique optical arrangement. The design of the apparatus further facilitates integration and scaling to produce arrays of units which may be particularly useful for magnetometry applications. Other important applications of the invention include laser frequency stabilization and atomic clocks.

Abstract: A method of determining lighting contributions of elements of a lighting component includes obtaining optical data representative of light output of the lighting component. Relative intensity data may be calculated from the optical data, and may indicate intensity differences in the light output of the lighting component as compared to that of a reference component. An optical property of an element of the lighting component is determined based on a comparison of the optical data with that of the reference component, where the reference component includes at least one reference element. Related systems and apparatus are also discussed.

Abstract: A method of measuring a relative phase of a bio-cell using a digital image sensor, comprising the steps of firstly filtering a light emitted from a light source, using a first polarizer and a first wave plate, which are arranged in order in a optical path, exposing a bio-cell to the firstly filtered light, secondly filtering the light passing through the bio-cell, using a second wave plate and a second polarizer, which are arranged in order in the optical path, and sensing an intensity of the secondly filtered light, by each of pixels of the image sensor, wherein, as conditions of the second filtering are varied, optical properties of the bio-cell are calculated using the intensity of the light in a pixel-wise manner.

Abstract: Systems and methods disclosed herein, in accordance with one or more embodiments, provide for processing infrared images. In one embodiment, a system includes an infrared sensor adapted to capture infrared images and a processing component adapted to process the captured infrared images by extracting a high pass part from the captured infrared images, extracting a mid-spatial frequency part from the captured infrared images, extracting a low pass part from the captured infrared images, separately scaling each of the parts, and merging the scaled parts to generate enhanced output images. The system may include a display component adapted to display the enhanced output images.

Abstract: A kit having a supporting device for maintaining a transparent article having a longitudinal axis A, a proximal end and a distal end. The supporting device including a proximal holder including a port intended to receive the proximal end of the article, and a distal holder including a receiving part intended to receive the distal end of the article, the port and the receiving part being aligned on the same longitudinal axis B. The supporting device further having a compressor for putting the article under longitudinal compression directed towards a center of the article, when the article is mounted on the supporting device with its longitudinal axis A aligned on the longitudinal axis B, and a polarimeter. The invention also pertains to a method for measuring the stress inside an article made of transparent material.

Abstract: A method and apparatus for analysing the three-dimensional electromagnetic field resulting from an interaction between a focused illuminating beam and a sample to be observed, by characterising the distribution of the state of polarization of light across a measurement plane, the method comprising the steps of generating a beam of illuminating light; controlling the state of polarization at different positions across the beam width of the light beam; focussing said illuminating light beam to a focus, wherein said focus is a tight focus and said focused light has a suitable three-dimensional vectorial structure at the focus; detecting and measuring the state of polarization of the reflected light at different positions across the width of the measurement plane to retrieve information on the three-dimensional vectorial electromagnetic interaction of the illuminated focused field and the sample.

Abstract: A device includes an incident arm, a detection arm, a sample stage, and an image processing computer. The incident arm includes a light source and a first polarizing element, and is disposed on one side of the sample stage. The detection arm includes a second polarizing element and a photoelectric detector, and is disposed on a light-detection path. The photoelectric detector is connected to the computer. The device further includes a device for adjusting polarization angles of the first and second polarizing elements. A method includes: illuminating a sample surface using linearly polarized light with a certain polarization angle; detecting outgoing polarized light by a photoelectric detector; adjusting polarization angles of the incident and detected polarized light, and repeating the above two steps to obtain a series of polarized images, each image corresponding to incident and detected polarization angles; and computer processing the obtained images to obtain sample information.

Abstract: This application describes a flow cell to perform experiments under well-controlled hydrodynamic conditions. The resulting cell enables combining the advantages of in-situ spectroscopic ellipsometry with stagnation point flow conditions. An additional advantage is that the proposed cell features a fixed position of the “inlet tube” with respect to the substrate, thus facilitating the alignment of multiple substrates. Theoretical calculations were performed by computational fluid dynamics and compared with experimental data (adsorption kinetics) obtained for the adsorption of polyethylene glycol to silica under a variety of experimental conditions. Additionally, a simple methodology to correct experimental data for errors associated with the size of the measured spot and for variations of mass transfer in the vicinity of the stagnation point is herein introduced.

Abstract: An imaging system for imaging skin includes a light source to illuminate a subject and a first polarizer to polarize light provided by the light source to illuminate the subject. The imaging system also includes a photodetector to acquire an image of the subject as illuminated by the light source and an adjustable second polarizer, coupled to the photodetector, to provide an adjustable degree of polarization of light received by the photodetector.

Abstract: This invention relates to the manufacture of semiconductor substrates such as wafers and to a method for monitoring the state of polarization incident on a photomask in projection printing using a specially designed polarization monitoring reticle for high numerical aperture lithographic scanners. The reticle measures 25 locations across the slit and is designed for numerical apertures above 0.85. The monitors provide a large polarization dependent signal which is more sensitive to polarization. A double exposure method is also provided using two reticles where the first reticle contains the polarization monitors, clear field reference regions and low dose alignment marks. The second reticle contains the standard alignment marks and labels. For a single exposure method, a tri-PSF low dose alignment mark is used. The reticles also provide for electromagnetic bias wherein each edge is biased depending on that edge's etch depth.

Abstract: A rotation detection kit, comprising: a beam source; a receiver comprising at least one beam intensity sensor; a polarizer device for location in the path of a beam emitted from the beam source and received by the beam sensor; and a modulator. The modulator is configured to modulate at least one of i) the beam source and ii) a beam emitted by the beam source to create a discretely varying polarization orientation thereby defining first and at least second temporally spaced beam portions. The temporally spaced beam portions are incident on the polarizer device and the beam sensor and have substantially identical profiles and at least an initial common propagation axis toward the polarizer device.

Abstract: An imaging polarimeter optics unit comprising: a first polarization-sensitive beam-splitter optic, a retarder, a second polarization-sensitive beam-splitter optic, and an analyzer, through which input light passes in sequence, wherein the retarder and polarization-sensitive beam-splitters cause the input light to have optical components that provide different information about the state of polarization of the input beam is provided.

Abstract: A rotation detection kit, comprising a source for generating at least a first polarized beam emitted along a propagation axis, a receiver comprising at least a first beam intensity sensor and an analyzer. The analyzer comprises a first polarizer device for location in the at least first polarized beam between the source and at least first beam intensity sensor. The first polarizer device is configured such that the receiver can measure rotation between the source and the analyzer about a first axis that is non-parallel to the propagation axis based on the at least first beam intensity sensor's output.

Abstract: Method and apparatus for testing of LCD cells is disclosed. An LCD cell under test (14, 30) may be mounted to translatable table (40) between polarization state generator (10) and polarization state analyzer (16). For each location on cell (14, 30) to be tested, a variety of known polarization states (22) are launched through LCD cell (14, 30) and detected by polarization state analyzer (16). Electrical signals representative of polarization states are acquired by computer (18). Within computer (18), a model (58, 60) of polarization properties of LCD cell (14, 30) is developed based on estimations of what physical parameters of LCD cell (14, 30) are believed to be. RMS differences between simulated polarization properties and measured polarization properties are minimized by iteratively refining (60) modeled physical cell properties, at which point cell thickness and other physical parameters of the LCD cell may be deduced.

Abstract: An imaging polarimeter and a method of utilizing the imaging polarimeter are provided. The method includes receiving a first light ray at a beam splitter and splitting the first light ray into second, third, fourth, and fifth light rays such that the second, third, fourth, and fifth light rays are simultaneously received on a flat focal plane. The method further includes outputting first, second, third, and fourth signals indicative of first, second, third, and fourth intensities, respectively, of the second, third, fourth, and fifth light rays, respectively, utilizing a sensor array disposed on the focal plane. The method further includes determining first, second, third, and fourth Stokes parameters for a pixel of the sensor array based on the first, second, third, and fourth signals, respectively, utilizing a computer.

Abstract: A polarimetric sensor includes a substrate and a plurality of aligned nanotube film patches arranged on the substrate. Each of the plurality of aligned nanotube film patches is oriented on the substrate to sense a different orientational component of electromagnetic radiation. For each of the plurality of aligned nanotube film patches, at least two contacts are arranged in electrical communication with the respective aligned nanotube film patch. The at least two electrodes are configured to conduct to an external circuit an electric signal generated in the respective aligned nanotube film patch when exposed to a respective orientational component of electromagnetic radiation.

Abstract: A device (2) for evaluating the state of wetting of a surface (8) includes an emitter (4) emitting a beam (F, F1, F2) which is incident in the direction of the surface (8) and a single element (12) for receiving the beam reflected by the surface (8). The device includes: A polarization (10, 13, 14) including a first polarization zone (13) and a second polarization zone (14) designed to polarize a first part (F1) and a second part (F2) of the beam in a first and a second polarization direction; and a evaluation element (28) for calculating a polarization ratio between the polarizations of the first part of the reflected beam and the second part of the reflected beam to evaluate the state of wetting of the surface (8). Also described is an evaluation process and an associated indicator device.

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 at least one odd-bounce polarization state image rotating system, and optionally including a polarizer, at least one compensator and/or modulator, in addition to an analyzer.

Abstract: A surface plasmon apparatus includes a light source, a sensor unit for Surface Plasmon Resonance (SPR) which includes a transparent sensor structure forming at least one wall of a cavity, the wall being defined by a concave inner surface and a convex outer surface, wherein the inner surface is provided with a layer of a conductive material capable of supporting a surface plasmon, a flow structure in the cavity so as to form at least one compartment for sample between the flow structure and the inner wall of the cavity, a detector for detecting reflected light from the sensor unit, and a processing unit.

Abstract: A polarization-sensitive infrared image sensor (also termed a snapshot polarimeter) utilizing a 2-D array of polarizers to filter infrared light from a scene according to polarization, and a 2-D array of photodetectors (i.e. a focal plane array) to detect the filtered infrared light and generate polarization information which can be used to form a polarization-sensitive image of the scene. By forming each polarizer on an optical fiber in a fiber optic faceplate, the polarizers can be located facing a 2-D array of retarders to minimize diffraction effects of the infrared light. The optical fibers also guide the filtered infrared light to the photodetectors to reduce cross-talk in the polarization information. The polarizers can be formed as wire grid polarizers; and the retarders can be formed as subwavelength surface-relief gratings.

Abstract: Control of the angle-of-incidence of a beam of electromagnetic radiation provided by a horizontally oriented arc-lamp in ellipsometer, polarimeter, spectrophotometer, reflectometer, Mueller matrix measuring, or the like systems.

Abstract: The invention provides spectroscopy apparatuses and methods allowing precise overlapping between circularly polarized pump beam and a counter propagating linearly polarized probe beams in a sample which presents unique advantages for precision spectroscopy. In general, the apparatus comprises a phase retarding element with which by double pass by retro reflection of an incident beam turn linearly polarized light to circular and vice versa. This unique configuration enable to design a compact and miniature apparatus which may be applied for measuring polarization spectroscopy, nonlinear optical rotation and coherent population trapping phenomena with certain advantages resulting from the unique optical arrangement. The design of the apparatus further facilitates integration and scaling to produce arrays of units which may be particularly useful for magnetometry applications. Other important applications of the invention include laser frequency stabilization and atomic clocks.

Abstract: A treatment pattern (such as a focused spot, an image, or an interferogram) projected on a treatment target may lose precision if the treatment beam must pass through a birefringent layer before reaching the target. In the general case, the birefringent layer splits the treatment beam into ordinary and extraordinary components, which propagate in different directions and form two patterns, displaced from each other, at the target layer. The degree of birefringence and the orientation of the optic axis, which influence the amount of displacement, often vary between workpieces or between loci on the same workpiece. This invention measures the orientation of the optic axis and uses the data to adjust the treatment beam incidence direction, the treatment beam polarization, or both to superpose the ordinary and extraordinary components into a single treatment pattern at the target, preventing the birefringent layer from causing the pattern to be blurred or doubled.

Abstract: The invention relates to a sensor unit for a Surface Plasmon Resonance (SPR) unit, comprising a transparent sensor structure forming at least one wall of a cavity, the wall being defined by a concave inner surface and a convex outer surface The inner surface is provided with a layer of a conductive material capable of supporting a surface plasmon. In the cavity there is provided a flow structure in said cavity so as to form at least one compartment for sample between the flow structure and the inner wall of the cavity. Also, a method for the detection of events at a surface by utilizing surface plasmon resonance is provided. It comprises placing a sample with an analyte of interest in a sensor unit as claimed in claim 1, and measuring the reflectance from said sensor unit at a single or plurality of angle/angles.

Abstract: A treatment pattern (such as a focused spot, an image, or an interferogram) projected on a treatment target may lose precision if the treatment beam must pass through a birefringent layer before reaching the target. In the general case, the birefringent layer splits the treatment beam into ordinary and extraordinary components, which propagate in different directions and form two patterns, displaced from each other, at the target layer. The degree of birefringence and the orientation of the optic axis, which influence the amount of displacement, often vary between workpieces or between loci on the same workpiece. This invention measures the orientation of the optic axis and uses the data to adjust the treatment beam incidence direction, the treatment beam polarization, or both to superpose the ordinary and extraordinary components into a single treatment pattern at the target, preventing the birefringent layer from causing the pattern to be blurred or doubled.