Abstract: Exemplary embodiments of apparatus, methods and systems according to the present disclosure can be provided for optical frequency domain imaging (e.g., partially fiber-based) to obtain information associated with an anatomical structure or a sample. For example, it is possible to provide at least one first electro-magnetic radiation, where a frequency of radiation associated with the first electro-magnetic radiation(s) varies over time. In addition, it is possible to separate at least one portion of a radiation which is (i) the first electro-magnetic radiation(s) and/or (ii) at least one further radiation into second and third radiations having difference orthogonal states, and to apply at least one first characteristic to the second radiation and at least one second characteristic to at least one third radiation. The first and second characteristics can be different from one another.

Abstract: Techniques and devices based on transverse magnetic (TM) and transverse electric (TE) modes in an optical resonator or interferometer to provide sensitive optical detection with insensitivity to a change in temperature. A shift in a difference between a first resonance wavelength of a TE optical mode and a second resonance wavelength of a TM optical mode is measured to measure a change in a sample that is in optical interaction with the optical resonator or interferometer. For example, the detected shift can be used to measure a change in a refractive index of the sample.

Abstract: Methods and compositions are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also provides optical devices useful as narrow band filters.

Abstract: A detour unit splits a light beam from a light source unit into first and second beams and makes the first beam travel longer than the second beam by a predetermined optical distance, and then combines the first and second beams into a single combined light beam. In the detour unit, a first ?/2 plate is disposed on an optical path of the first beam. A second ?/2 plate is disposed on an optical path of the second beam. Directions of optical axes of the first and second ?/2 plates are different from each other by 45 degrees. A ?/4 plate is disposed on an optical path between the detour unit and a beam expanding unit. Thereby, the first and second beams are converted into two circularly polarized beams having opposite rotation directions, respectively.

Abstract: An interrogation apparatus and method use a partial shear optical interference apparatus to interrogate the optical properties of an array of target specimen probe volumes as compared to an array of reference sample probe volumes. The apparatus produces a formatted probe beam that contains a partially sheared probe beam pair that is formatted into an array of completely sheared probe beam pairs. Target specimen probe volumes and reference sample probe volumes are suitably organized and exposed to the array of completely sheared probe beam pairs.

Abstract: Techniques and devices for measuring the distribution of polarization crosstalk in birefringence optical media including polarization maintaining fiber based on suppressing the number and magnitude of ghost interference peaks.

Abstract: A device for imaging scenes with a very large range of intensity having a pair of polarizers, a primary lens, an attenuating mask, and an imaging device optically connected along an optical axis. Preferably, a secondary lens, positioned between the attenuating mask and the imaging device is used to focus light on the imaging device. The angle between the first polarization direction and the second polarization direction is adjustable.

Abstract: A method for controlling a transformation process in which the conversion of charge materials to a product takes place along a transformation interface from the crystal and/or grain and/or phase and/or pore surface into the charge material, wherein one or more chemical elements in the charge materials is released and/or incorporated and/or rearranged and wherein the conversion of the charge materials takes place along advancing transformation interfaces. The charge materials are identified on the basis of at least one optical, in particular microscopic, analysis with respect to their phases and/or phase components and/or their phase morphology, structure, texture and/or their chemical composition. On the basis of these variables, reference functions for the charge materials, which describe the conversion of the charge materials in the process, are assigned and used for establishing the process parameters of the transformation process.

Abstract: A method and apparatus for extracting the vector optical properties of biological samples with micron-scale resolution in three dimensions, using polarization-sensitive optical coherence tomography (PS-OCT). The method measures net retardance, net fast axis, and reflectivity. Polarization sensing is accomplished by illuminating the sample with at least three separate polarization states, using consecutive acquisitions of the same pixel, A-scan, or B-scan. The method can be implemented using non-polarization-maintaining fiber and a single detector. This PS-OCT method reported measures fast axis explicitly. In a calibration test of the system, net retardance was measured with an average error of 7.5° (standard deviation) 2.2° over the retardance range 0° to 180°, and fast axis with average error of 4.8° over the range 0° to 180°.

Abstract: An adaptive optics apparatus includes a light modulation unit configured to modulate each of two polarization components of light at a position that is optically conjugate to an object, the light being emitted by a light source; and an irradiation unit configured to irradiate the object with light that is modulated by the light modulation unit.

Abstract: A delay interferometer includes first and second optical paths into which incident signal light is split, a first converter including one or more conversion parts to convert the signal light on the first optical path into circularly polarized light and to convert the circularly polarized light into linearly polarized signal light, a phase adjuster to shift an optical phase of the circularly polarized light through a magneto-optic effect, and a second converter to convert a polarization state of the signal light on the second optical path into substantially the same polarization state as a polarization state of the linearly polarized signal light.

Abstract: High-resolution, common-path interferometric imaging systems and methods are described, wherein a light source generates and directs light toward a sample. An optical imaging system collects the resultant substantially scattered component and substantially unscattered component. A variable phase shifting system is used to adjust the relative phase of the scattered and unscattered light components. The interfered components are sensed by an image sensing system. The process is repeated multiple times with different phase shifts to form corresponding multiple electronic signals representative of raw sample images. The raw sample images are then processed by a signal processor to form a processed image, where each image pixel has an amplitude and a phase. This picture can be displayed directly using some combination of brightness and color to represent amplitude and phase.

Abstract: A compact OCT-like scanning device reduces radiation back-propagating to the radiation source by means of a polarized optical element that is reflective for linearly polarized light or radiation at one orientation and which is transmissive for radiation orthogonal to the reflected linearly polarized light or radiation. The device is also compatible with viewing the surface of the target being scanned either directly by visual means or by means of a camera.

Abstract: According to one embodiment, a pattern inspection apparatus includes a light source, a beam splitter, a first optical system, a second optical system, a controller, a phase controller and a detector. The beam splitter splits an emitted light into first and second optical paths. The first optical system delivers the light to a first pattern and delivers a first reflected light from the first pattern. The second optical system delivers the light to a second pattern and delivers a second reflected light from the second pattern. The controller is provided on the optical path, and intensities of the first and second reflected lights are substantially equal. The phase controller is provided on the optical path, and phases of the first and second reflected lights are inverted. In addition, the detector detects a light that the first and second reflected lights are made to interfere with each other.

Abstract: The present invention discloses an interference measuring apparatus, which comprises a light source module, a beam splitter, a first lens module, a reflecting module, a second lens module, and a detection device. A light beam generated from the light source module can be projected on the beam splitter. The beam splitter splits the light beam to generate a first light beam and a second light beam, wherein the first light beam passes through the first lens module and then projects onto the reflecting module, and the second light beam passes through the second lens module and projects onto an object. Furthermore, the first light beam and the second light beam are reflected by the reflecting module and the object, respectively, then both the first light beam and the second light beam are leaded to the detection device to form an interference pattern for obtaining the contours and internal cross-sectional image of the object.

Abstract: An optical device for changing polarization comprises a waveguide having a waveguide end facet coupled to a quarter-wave plate/reflector combination to rotate the polarization of incident light to the waveguide by 90 degrees. In one embodiment, a polarization beam splitter/rotator combination (PBSR) uses a quarter-wave plate in reflection at the end facet of the waveguide. The polarization beam splitter/rotator combination and variations of that structure are applied in various useful topologies as polarization mode dispersion (PMD) compensators and polarimeters.

Abstract: A quantum entanglement generating system (30) comprises: a laser light source (1) for producing a light beam of light frequency 2f0; a ring interferometer (20) comprising a beam splitter (4) into which the light beam of light frequency 2f0 is incident and a plurality of mirrors (5, 7, 8), the beam splitter and the mirrors forming an optical path in the form of a ring; a parametric amplifier (6) inserted in the optical path of the ring interferometer for producing a beam of light of light frequency f0 upon receiving the light beam of light frequency 2f0 incident into the optical parametric amplifier; and a dispersive medium (9) inserted in the optical path of the ring interferometer for varying relative optical path length for the light beam of light frequency 2f0 and the light beam of light frequency f0, whereby two light beams of light frequency 2f0 split into at the beam splitter (4) so as to travel mutually contrariwise in direction of advance in the ring interferometer are incident into the optical parame

Abstract: An apparatus is provided which reduces the dependency of the direction of polarization on channels of an image sensor so as to improve the sensitivity of inspection. In the apparatus, the direction of an illumination beam incident on a polarizing beam splitter is made to be substantially parallel to the longitudinal direction of a field of view of an image sensor projected on the polarizing beam splitter.

Abstract: A tunable optical spectrometer is disclosed that includes a medium configured to perform polarization rotation within a frequency band on a linearly polarized test beam, wherein the medium is circularly birefringent, and wherein the polarization rotation is achieved based on two-photon-absorption. The medium includes a gaseous substance, a reference laser beam of circular polarization and a longitudinal magnetic field. The test beam propagates through the medium twice, once in the same direction as the magnetic field, and once in the opposite direction of the magnetic field. The test beam undergoes polarization rotation an amount that depends upon the frequency of the test beam.

Abstract: A beam of coherent laser light with linear polarization oriented at 45 degrees to vertical is expanded, and passes through a quarter-wave plate with the fast axis oriented vertically, creating circularly polarized light. The light then passes through a non-polarizing 50/50 beamsplitter. A partial reflector then collinearly reflects a portion of the beam, which is used as the reference beam. The transmitted light passes through a linear polarizer oriented at 45 degrees to vertical, and is focused via a lens onto the sample of interest. Light scattered from this region is re-collimated by the lens and the directed through the linear 45 degree polarizer and through the partial reflector, where it recombines with the reference beam. One use of the invention is to detect microparticles in water.

Abstract: An apparatus for determining a polarization-insensitive interferometric signal and a birefringence for a sample and methods for using such an apparatus to characterize the sample are proved herein. Such apparatuses may generally be designed to eliminate birefringence associated with the apparatus itself, collect data from the sample using light in both orthogonal states, and determine the interference birefringence associated with the collected data.

Abstract: A system for detecting piston diversity between mirror segments. The system includes a pupil plane mask, a transform optical element, and an image detector. The pupil plane mask includes two or more open mask areas and two or more polarizers. Each polarizer is disposed within a respective one of the open mask areas. A first one of the two or more polarizers has a first polarization orientation, and a second of the two or more polarizers has a second polarization orientation.

Abstract: In a delay line interferometer inside a demodulator, with respect to polarization states of two split beams of light to be interfered with each other, p polarization and s polarization are reversed by a half beam splitter and, further, again multiplexed by the half beam splitter used for splitting so that interference beams of light are generated.

Abstract: The present invention relates to a high-resolution scanning surface-plasmon microscope including a source (LG) of coherent light and a medium for coupling and confining a surface plasmon including an objective (O, OM) with a large numerical aperture, immersion oil (Hi), and a glass cover slip (GS). A metal layer (MS) covers a surface of the glass cover slip (GS). The microscope also includes a heterodyne-mode Twyman-Green interferometer placed between the light source and means (PL1, PL2, EC) for scanning the metal layer using a light beam and means (PD) for detecting the beam from the interferometer connected to processing means (S, F, DTec, COMP) for forming an image from that beam. According to the invention, at least one polarization converter (CP) for converting the light beams (L) emitted by the light source (LG) from linear polarization to radial polarization is disposed between the light source and the interferometer.

Abstract: An interferometer of the present invention includes: a splitting element which splits an incident light beam into a first split beam and a second split beam; and a first phase compensator which is positioned in an optical path of the first split beam, and which compensates a phase difference occurring between the first split beam and the second split beam upon splitting of the incident light beam by said splitting element.

Abstract: A method of coupling optical energy comprising: generating a first beam of optical energy; generating a second beam of optical energy coherent with the first beam; polarizing optical energy from the first and second beams in a same direction; and transmitting the polarized optical energy from the first and second beams into a photorefractive body so that the energy interferes in the body to generate an interference pattern that is extant in substantially all the volume of the body.

Abstract: An apparatus is provided which reduces the dependency of the direction of polarization on channels of an image sensor so as to improve the sensitivity of inspection. In the apparatus, the direction of an illumination beam incident on a polarizing beam splitter is made to be substantially parallel to the longitudinal direction of a field of view of an image sensor projected on the polarizing beam splitter.

Abstract: The present invention relates to near-field scanning optical microscopy (NSOM) and near-field/far-field scanning microscopy methods, systems and devices that permit the imaging of biological samples, including biological samples or structures that are smaller than the wavelength of light. In one embodiment, the present invention permits the production of multi-spectral, polarimetric, near-field microscopy systems that can achieve a spatial resolution of less than 100 nanometers. In another embodiment, the present invention permits the production of a multifunctional, multi-spectral, polarimetric, near-field/far-field microscopy that can achieve enhanced sub-surface and in-depth imaging of biological samples. In still another embodiment, the present invention relates to the use of polar molecules as new optical contrast agents for imaging applications (e.g., cancer detection).

Abstract: A sensor platform for use in sample analysis comprises a substrate (30) of refractive index (n1) and a thin, optically transparent layer (32) of refractive index (n2) on the substrate, (n2) is greater than (n1). The platform incorporates one or multiple corrugated structures in the form of periodic grooves (31), (33), which defines one or more sensing areas each for one or more capture elements. The grooves are so profiled, dimensioned and oriented that when coherent light is incident on the platform it is diffracted into individual beams or diffraction order resulting in reduction of the transmitted beam and an abnormal high reflection of the incident light thereby creates an enhanced evanescent field at the surface of the or each sensing area. The amplitude of this field at the resonant condition is greater by an order of approximately 100 than the field of prior art platforms so that the luminescence intensity created from samples on the platform is also increased by a factor of 100.

Abstract: A interferometer includes a first splitter for splitting one of a signal and a reference lights into a first and a second branch lights; a second splitter for splitting the other of a signal and a reference lights into a third and a fourth branch lights; a first coupler for causing the first and the third branch lights to interfere with each other, and outputting a first detection light; a second coupler for causing the second and the fourth branch light to interfere with each other, and outputting a second detection light; a first polarization phase controller provided between the first beam splitter and the first coupler, and outputting the phase-controlled polarization components of the first branch light; and a second polarization phase controller provided between the second beam splitter and the second coupler, and outputting the phase-controlled polarization components of the fourth branch light.

Abstract: Method and apparatus for noise reduction in ultrasound detection with the steps of: an optical interferometer having a reference arm and a signal arm that includes a polarization-maintaining probing fiber having a reflective coating at a distal end, a way to couple the probing fiber to ultrasound, a way to generate two output beams from the interferometer, a device to modulate the polarization state of the light in the probing fiber, and a detection mechanism responsive to the ultrasonic signals at the distal tip of the probing fiber.

Abstract: The present invention provides a biochip for testing biological substances comprising a plurality of binding sites, optical means for determining a specific binding event at each binding site, wherein the plurality of binding sites and the means for determining a specific binding event at each binding site are monolithically integrated into a single chip which is electrically powered and produces electrical signals in response to binding events at each binding site. The means for determining a specific binding event can include a micro-cavity light source formed in a semiconductor layer and a photodetector formed in the same semiconductor layer and further include a grating assisted vertical planar waveguide coupler for in-situ monitoring hybridization dynamics at each binding site via associated changes in refractive index.

Abstract: Embodiments include apparatuses and methods for spectral domain polarization sensitive optical coherence tomography including a reference assembly for detection of the polarization sensitive spectral interferograms formed by vertically and horizontally polarized beam components. Interference signals between the reference and sample beams may be modulated at a constant frequency.

Abstract: A method and apparatus for simultaneously acquiring interferograms created with a plurality of different interference conditions are provided in the present invention. In the present invention, an object beam and a reference beam are used to interfere with each other and there are a plurality of sub-fields of interference simultaneously generated. All the sub-fields of interference can be simultaneously acquired by an image acquiring device with single shooting action so as to form the plurality of interferograms. Moreover, the present invention also provides a method for solving the phase information of the object beam from the interferograms formed by the foregoing said method.

Abstract: An optical system including: a photon source; first directing elements configured to direct photons to follow a first path through the optical system; second directing elements configured to direct photons to follow a second path through the optical system, wherein the second path is the reverse of the first path, photons travelling through the first path having a different polarization to those travelling through the second path; and a mechanism varying the relative phase shift between photons following the first path and photons following the second path.

Abstract: The subject of the present invention is a laser anemometry probe for optical homodyne detection of frequency offset by Doppler effect, comprising two devices (DERF1, DERF2) for transmitting/receiving beams in two different directions, avoiding duplicating a plurality of elements of a mono-axial laser anemometry probe.

Abstract: A wavelength shift measuring apparatus of the present invention is a wavelength shift detection sensor (WLCD1) which measures a shift of a wavelength of a light beam emitted from a light source, and includes a beam splitter (BS2) splitting the light beam emitted from the light source into a plurality of light beams and to synthesize two light beams among the plurality of light beams to generate an interference light, a spacer member (SP) provided so that an optical path length difference of the two light beams split by the beam splitter (PBS2) is constant, and a plurality of photoelectric sensors (PD) detecting the interference light generated by the beam splitter (BS2). The plurality of photoelectric sensors (PD) output a plurality of interference signals having phases shifted from one another based on the interference light to calculate a wavelength shift using the plurality of interference signals.

Abstract: A system for measuring an electric field vector includes an optical extractor configured to extract an optical signal having a spatial resolution of a nanometer level. The optical signal corresponds to incident light at a measuring position within an examination area of a surface of a specimen. The system further includes a polarization analyzer for analyzing a polarization characteristic of the optical signal extracted by the optical extractor, and an electric field vector determinator for determining at least a size and an orientation axis of an electric vector at the measuring position using the polarization characteristic analyzed by the polarization analyzer.

Abstract: An improved condition testing system and method integrated into microelectronic circuits includes a structure including a semiconductor material with a target portion and a second portion for determining the presence and nature of various external (e.g. magnetic field, microwave, bioelectric or incident radiation) or internal stresses (e.g. binary circuit-state or analog signal recognition) or conditions acting upon the material. The target portion has a first feature when at least one of the following occurs: an external force is received by the second portion of the structure and an internal condition occurs in the target portion. The system and method further has a test grating determined and shaped and located to produce a first optical interference pattern when the target portion and the grating are exposed to non-invasive illumination and when the target portion has the first feature.

Abstract: Preferred embodiments of the present invention are directed to systems for phase measurement which address the problem of phase noise using combinations of a number of strategies including, but not limited to, common-path interferometry, phase referencing, active stabilization and differential measurement. Embodiment are directed to optical devices for imaging small biological objects with light. These embodiments can be applied to the fields of, for example, cellular physiology and neuroscience. These preferred embodiments are based on principles of phase measurements and imaging technologies. The scientific motivation for using phase measurements and imaging technologies is derived from, for example, cellular biology at the sub-micron level which can include, without limitation, imaging origins of dysplasia, cellular communication, neuronal transmission and implementation of the genetic code.

Abstract: Optical filters tunable for both center wavelength and bandwidth, having applications such as in astronomy, remote sensing, laser spectroscopy, and other laser-based sensing applications, using Michelson interferometers or Mach-Zehnder interferometers modified with Gires-Tournois interferometers (“GTIs”) are disclosed. A GTI nominally has unity magnitude reflectance as a function of wavelength and has a phase response based on its resonator characteristics. Replacing the end mirrors of a Michelson interferometer or the fold mirrors of a Mach-Zehnder interferometer with GTIs results in both high visibility throughput as well as the ability to tune the phase response characteristics to change the width of the bandpass/notch filters. A range of bandpass/bandreject optical filter modes, including a Fabry-Perot (“FP”) mode, a wideband, low-ripple FP mode, a narrowband notch/bandpass mode, and a wideband notch/bandpass mode, are all tunable and wavelength addressable.

Abstract: The invention relates to an interferometer, comprising a light source, adapted to generate a coherent light beam, a detector adapted to analyze the phase difference of optical light beams, location means for locating an object to be measured, a first optical path from the light source to the object and a second optical path from the object to the detector, wherein the first and the second optical path have a common section adjacent to the object, wherein an optical polarization modulator has been arranged in the first path. This avoids the costs and other disadvantages of so called quarter wave plates belonging to prior art interferometers of this kind.

Abstract: Interferometers and autocorrelator based sensors are disclosed that are configured to have multiple sample arms which can be scanned and the backscattered low coherence source light from a sample resolved in a single sweep of one or more variable delays of the sensor. Borescopes and catheters capable of scanning multiple sections or areas of materials and tissues using these sensors are described.

Abstract: Methods for displaying anisotropic properties of an object. The object is illuminated with a first test beam characterized by a first polarization that, after traversing the object, is combined with a reference beam. The combined light of the first transmitted test beam and the reference beam is analyzed by a first pair of polarization analyzers, and interference created between the first transmitted test beam and the reference beam as analyzed by the first pair of analyzers is detected to derive intensity, phase and polarization of the first transmitted test beam. The same is then done with a second test beam that has a polarization with a component orthogonal to the first polarization. Based on the two analyzed beams, complex elements of a Jones matrix associated with the object in a local coordinate system are determined and a plurality of tangible images are displayed that characterize the object based on the complex elements of the Jones matrix.

Abstract: An optical nonlinear evaluation device (1) capable of accurately evaluating the optical nonlinearity of a Kerr medium in accordance with a phase difference caused by cross-phase modulation generated in the Kerr medium includes: a polarization Sagnac interference path (3) provided with a Kerr medium (4); an optical pulse light source (7) for supplying a signal beam (Dsig); a polarization beam splitter (PBS1) for splitting the signal beam (Dsig) into a signal beam (Hsig) and a signal beam (Vsig) polarized in a direction orthogonal to the signal beam (Hsig), for supplying the signal beam (Hsig) to a first side of the Kerr medium (4), and for supplying the signal beam (Vsig) to a second side of the Kerr medium (4); a glass plate (14) for entering, onto the signal beam (Hsig), a control beam (Vcont) for causing a change in phase difference between the signal beam (Hsig) and the signal beam (Vsig); separating means for separating the control beam (Vcont) from the signal beam (Hsig) having traveled through the Kerr

Abstract: An interferometer includes a cavity including a pair of mirrors defining a cavity length. An input beam and a counter-propagating reference beam are directed into the cavity. The interferometer generates a feedback control signal and an ultrasound signal for optimal performance and measurement of a target, respectively.

Abstract: A device for measuring polarization mode dispersion (PMD) in a device under test (DUT) includes a polarized light source for launching a test beam through the DUT, and a PMD analyzer, which uses one of a plurality of known techniques, e.g. fixed analyzer-Fourier transform (FA-FT) or interferometric, to calculate the PMD from the DUT. A passive depolarizer, made up of a plurality of birefringent elements is disposed between the light source and the PMD analyzer to generate a plurality of carrier frequencies that correspond to the delays imposed by the birefringent elements. The PMD content of the DUT is present around each of the carriers, and the plurality of PMD measurements can be averaged to obtain a more accurate and repeatable measure of the PMD.

Abstract: Techniques and devices based on transverse magnetic (TM) and transverse electric (TE) modes in an optical resonator or interferometer to provide sensitive optical detection with insensitivity to a change in temperature.

Abstract: There is disclosed a phase sensitive surface plasmon resonance sensing apparatus wherein a testing beam may be reflected from a sensing surface at a plurality of angles. There are also disclosed methods for surface plasmon resonance sensing.

Abstract: Provided are techniques for generating optical vector beams (e.g., radially and azimuthally polarized light) using passive or active phase stable optical interferometry. Techniques may split an input optical beam into at least two output beams, and then couple those beams simultaneously into a passively phase stable optical interferometer. Beam splitting may be achieved by a diffractive optical element and coupling may be achieved by a single refractive optical device (lenses) or by a single mirror device (e.g., parabolic and spherical). The interferometer may provide the ability to manipulate (or transform) the polarization of part of the wavefront of each beam, as well as the ability to manipulate (or transform) the phase of part of the wavefront of each beam, such that the beams when combined have a vector beam polarization state.