Class / Patent application number | Description | Number of patent applications / Date published |
356521000 | Having wavefront division (by diffraction) | 64 |
20080198388 | MINIATURE FOURIER TRANSFORM SPECTROPHOTOMETER - The Miniature Fourier Transform Spectrophotometer provides the capability, in a miniaturized device, of determining the light absorption/transmission spectra of a collected sample of gas or liquid though Fourier Transform spectroscopy techniques. The device takes an optical input from an optical fiber, manipulates that light through miniature optical components, and launches it into a miniaturized Michelson interferometer with a scanning mirror that acquires the interferogram of the optical input. The interferogram can be processed to retrieve the spectrum of the input light. A novel multi-stepped micro-mirror operates as the optical path length modulator in the miniaturized interferometer. A unique monolithic beamsplitter/mirror combination provides for accurate alignment of the components and greatly simplifies product integration. The device is designed to cover various optical spectra of interest. During operation, the precision and accuracy of the microfabricated components in the device allow operation and resolution even at extremely low wavelengths. In addition, the miniaturized nature of the device allows it to be used in new and extremely space-constrained applications. | 08-21-2008 |
20080204762 | Methods, systems, and computer program products for removing undesired artifacts in fourier domain optical coherence tomography (FDOCT) systems using integrating buckets - Methods, systems, and computer program products for removing undesired artifacts in Fourier domain optical coherence tomography (FDOCT) systems using integrating buckets are disclosed. According to one aspect, a method includes introducing a variable phase delay between a reference arm and a sample arm of an FDOCT interferometer using sinusoidal phase modulation. Further, the method includes acquiring an interferometric intensity signal using an integrating buckets technique. The method also includes resolving the interferometric intensity signal to remove undesired artifacts. | 08-28-2008 |
20080212105 | APPARATUSES AND METHODS FOR EVALUATING PERFORMANCE OF OPTICAL SYSTEMS - A system for evaluation of optical quality of an optical device includes a light source configured to generate light, the generated light be received by an optical device. An interferometric lens apparatus is removably mounted to the optical device to generate interference fringes. A camera device is configured to receive and display the interference fringes, and a computer configured to analyze the interference fringes received from the camera device to determine aberrations of the optical device and generate a recommendation to correct the determined aberrations. Methods for evaluating the optical quality of an optical device are also described. | 09-04-2008 |
20080231862 | Device and Method for the Interferometric Measurement of Phase Masks - A device and method for the interferometric measurement of phase masks, particularly from lithography. Radiation passing through a coherence mask is brought to interference by a diffraction grating. A phase mask is arranged in or near the pupil plane of the first imaging optics which can be positioned exactly in the x-y direction by which interferograms are generated which are phase-shifted in the x-y direction by translational displacement of the coherence mask or of the diffraction grating. The interferograms are imaged onto the spatially resolving detector by second imaging optic and the phase and transmission functions of the phase mask are determined by an evaluation unit. The invention can, of course, generally be applied to planar phase objects, such as biological structures, for example, points of establishment with respect to an interference microscope. | 09-25-2008 |
20080246972 | Tomographic Imaging by an Interferometric Immersion Microscope - A device for the tomographic imaging of an object to be analyzed, the device comprising a light source that emits a light beam with a coherence length substantially equal to the thickness of a slice of the object to be analyzed; and an interferometric imaging system comprising at least one objective, a reference mirror and a light-beam splitting means; wherein the interferometric system is arranged so that the objective defines a first focusing plane at the slice of the object to be analyzed and a second focusing plane at the reference mirror, and wherein the interferometric imaging system comprises at least a first compensating medium positioned between the second focusing plane and the splitting means, the thickness and the optical index of the at least one compensating medium having optical properties such that a first optical path of the light beam emitted from the light source between the first focusing plane and the splitting means is substantially equal to a second optical path of the light beam between the second focusing plane and the splitting means and such that a first dispersion between the first focusing plane and the splitting means is substantially equal to a second dispersion of the light beam between the second focusing plane and the splitting means. | 10-09-2008 |
20080259350 | MEASUREMENT APPARATUS, EXPOSURE APPARATUS, AND DEVICE FABRICATION METHOD - A measurement apparatus which measures a wavefront aberration of an optical system to be measured, the apparatus comprises a detection unit configured to detect an interference pattern formed by light having passed through a mask inserted on an object plane of the optical system to be measured, and a mask inserted on an image plane of the optical system to be measured. | 10-23-2008 |
20080291467 | DETERMINING ONE OR MORE PROFILE PARAMETERS OF A PHOTOMASK COVERED BY A PELLICLE - Provided is a method of determining one or more profile parameters of a photomask covered with a pellicle, the method comprising developing an optical metrology model of a pellicle covering a photomask, developing an optical metrology model of the photomask, the photomask separated from the pellicle by a medium and having a structure, the structure having profile parameters, the optical metrology model of the photomask taking into account the optical effects on the illumination beam transmitted through the pellicle and diffracted by the photomask structure. The optical metrology model of the pellicle and the optical metrology model of the photomask structure are integrated and optimized. At least one profile parameters of the photomask structure is determined using the optimized integrated optical metrology model. | 11-27-2008 |
20080316500 | Methods of testing and manufacturing optical elements - A method of manufacturing an optical element having an optical surface of a non-rotationally symmetric shape is described. Measuring light is generated using an interferometer optics, wherein the interferometer optics has at least one diffractive component having a grating. The optical surface is positioned at a first position relative to the diffractive component, wherein first measuring light diffracted at the diffractive component is incident on the optical surface at plural locations thereof, and at least one first interference pattern generated from first measuring light reflected from the optical surface is detected. The optical surface is positioned at a second position relative to the at least one diffractive component, wherein second measuring light diffracted at the diffractive component is incident on the optical surface at plural locations thereof, and at least one second interference pattern generated from second measuring light reflected from the optical surface is detected. | 12-25-2008 |
20090002717 | CONDITION ASSESSMENT SYSTEM FOR A STRUCTURE INCLUDING A SEMICONDUCTOR MATERIAL - An improved condition testing system and method includes a structure including a semiconductor material with a target portion and a second portion. 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 grating 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. Further implementations use a second grating spaced apart from the first grating. | 01-01-2009 |
20090040531 | Optical Fly Height Measurement - An optical fly height measurement system includes a planar waveguide, a first diffraction grating for coupling an electromagnetic wave into the planar waveguide wherein the first diffraction grating is positioned for directing the electromagnetic wave towards an air bearing surface of a slider. A second diffraction grating is provided for receiving the electromagnetic wave reflected from the air bearing surface. A detector module and processor are provided to determine the fly height. | 02-12-2009 |
20090046298 | Optical lattice microscopy - An optical system includes a substrate adapted for supporting a sample, where the substrate has a refractive index, n | 02-19-2009 |
20090051927 | OPTICAL SCATTERING DISK, USE THEREOF, AND WAVEFRONT MEASURING APPARATUS - Optical scattering disk, use and wavefront measuring apparatus. The optical scattering disk includes a transparent substrate ( | 02-26-2009 |
20090051928 | Method for analyzing a wavefront through frequency difference multilateral interferometry - The method comprises positioning a diffraction grating with a two-dimensional meshing on the path of the beam to be analyzed and processing at least two interferograms of at least two different colors, each interferogram being obtained in a plane from two sub-beams with different diffraction orders. The invention can be used to analyze and correct divided wavefronts. | 02-26-2009 |
20090073459 | WAVEFRONT MEASURING APPARATUS FOR OPTICAL PICKUP - A wavefront measuring apparatus for optical pickup includes: a beam splitting section; a wavefront shaping section; a beam combining section that generate interference light; an interference fringe image-acquiring section that acquires an interference fringe image including wavefront information of the light beam; and an analyzing section that analyzes a wavefront of the light beam on the basis of the interference fringe image. The analyzing section includes: an image processing section that performs a filtering process on the interference fringe image to eliminate a frequency component corresponding to the sub beam, so as to acquire the filtering-processed interference fringe image, and a wavefront analyzing section that analyzes a wavefront of the main beam on the basis of the filtering-processed interference fringe image. | 03-19-2009 |
20090103106 | OPITCAL PICKUP - To reduce a bad influence on a tracking control signal and a data signal by reflected light from an adjacent layer on a multi-layer disc as stray light, the following device is made in the invention. Reflected light from the multi-layer optical disc including stray light from another layer is once converged by a reflected light condenser lens and is reflected on a reflector. A grating which prevents zero-order light from being generated by setting groove depth to λ/4 and which is set to pitch to prevent positive and negative first- or higher-order diffracted lights from returning to the reflected light condenser lens is arranged between the lens and the reflector including an optical axis with the grating apart from the reflector. Hereby, as reflected light from another layer is cut off though reflected light from a corresponding layer is transmitted to a detector, a detected control signal and a detected data signal are not influenced by reflected light from another layer. | 04-23-2009 |
20090109446 | Zeroeth Order Imaging - A method of imaging critical dimensions by measuring the zeroeth order of diffracted light. The method involves providing a target, directing light onto the target so as to cause the target to diffract the light. The zeroeth order of the diffracted light is collected and analyzed to determine structural features of the target. The target can be an article of manufacture, such as a semiconductor device, or a separate target that is provided or fabricated on an article of manufacture. One of at least the wavelength and the angle at which the light is directed onto the target can be scanned. The target can fill all or only a portion of the field of view. | 04-30-2009 |
20090116036 | Device and Method for the Optical Measurement of an Optical System, Measurement Structure Support, and Microlithographic Projection Exposure Apparatus - A device for the optical measurement of an optical system which, in a useful operating mode, receives useful radiation on a useful radiation entrance side and emits it on a useful radiation exit side. The device includes a measurement radiation source, by which at least one exit-side element, which emits measurement radiation to the optical system, can be positioned on the useful radiation exit side of the optical system, and a detector, by which at least one entrance-side element, which receives measurement radiation coming from the optical system, can be positioned on the useful radiation entrance side of the optical system. The measurement radiation source includes a source-side measurement structure mask for positioning on the useful radiation exit side and/or the detector includes a detector-side measurement structure mask for positioning on the useful radiation entrance side. Also provided are a measurement structure support that can be used for such a device, a microlithography projection exposure apparatus equipped with such a device, and an associated method. The device can be used, e.g., for the wavefront measurement of projection objectives of microlithography projection exposure apparatuses. | 05-07-2009 |
20090128829 | METHOD AND APPARATUS FOR DETERMINING A DEVIATION OF AN ACTUAL SHAPE FROM A DESIRED SHAPE OF AN OPTICAL SURFACE - A method of determining a deviation of an actual shape from a desired shape of an optical surface ( | 05-21-2009 |
20090128830 | INTERFEROMETER DEVICE AND METHOD - The present invention discloses an interferometer device and method. In embodiments, the device comprises an electromagnetic radiation source emitting radiation having a first mean wavelength λ | 05-21-2009 |
20090135432 | Optical lattice microscopy - A microscope includes a source of electromagnetic radiation, having a wavelength, λ | 05-28-2009 |
20090153876 | OPTICAL IMAGE MEASUREMENT DEVICE - An optical image measurement device comprises: a light source configured to output a light having low temporal coherence and low spatial coherence; an optical system configured to split the light into a signal light and a reference light and superimpose the signal light having passed through a measured object and the reference light, thereby generating an interference light; a light receiver configured to receive the interference light and output an electric signal; and a forming part configured to form an image of the measured object based on the electric signal, wherein: the light receiver has a light receiving face on which a plurality of light receiving elements are arranged 2-dimensionally; and the optical system projects the interference light onto the light receiving face so that a size of the spatial coherent region of the interference light becomes equal to or larger than a size of the light receiving element. | 06-18-2009 |
20090161115 | Wavefront sensor - In a wavefront sensor, an optical wavefront to be measured that has entered an entrance pupil P is split into a first optical path L | 06-25-2009 |
20090185195 | INTERFERENCE OBJECTIVE FOR ANNULAR TEST SURFACES - An apparatus including: an interferometric objective comprising a beam splitter surface configured to separate input light into test light and reference light, and a reference surface configured to receive the reference light and direct it back to the beam splitter surface, which is configured to recombine the reference light with test light reflected from a test surface, the interferometric objective further comprising one or more optical elements positioned in the path of the input light and having positive or negative optical power, wherein the reference surface is curved and defines a window to pass the input light towards the beam splitter surface. | 07-23-2009 |
20090195789 | Biosensing Apparatus And Method Using Optical Interference - A label-free interferometric biosensor is disclosed which is based on the self-mixing optical interferometer. Inside the biosensor, an incoming beam is divided into two beam portions which pass through a channel and bio materials, respectively. Interference of the portions is realized by the self-mixing effect and used to detect existence of an analyte, such as DNA or protein molecules. The label-free biosensor is compact and can be made on a chip using the semiconductor technology. It is also convenient to use due to moderate alignment requirement. Furthermore, an array of the interferometers fabricated on a chip enables high-throughput and highly parallel measurements. | 08-06-2009 |
20090201512 | Compact achromatic optical interferometer of the three-wave lateral shearing type - A method and a system for analyzing the wavefront of a light beam, wherein a diffraction grating is arranged in a plane perpendicular to the light beam to be analyzed and optically conjugated to the analysis plane. Different emerging beams of the grating interfere to generate an image having deformations linked to the gradients of the wavefront to be analyzed. | 08-13-2009 |
20090207419 | Large areas undistorted imaging apparatus for light speckles and method thereof - The present invention relates to a large area undistorted imaging apparatus for light speckles and a method thereof. The large area undistorted imaging apparatus for light speckles comprises a light-emitting device, a light-limiting module, and a sensor. The light-limiting module is adapted in front of the sensor, and includes a plurality of light-limiting members. The light-limiting members are arranged in a one- or two-dimensional array. When the light-emitting device emits light to an object surface, one or more rays of scattered light are produced. By means of the light-limiting module, said one or more rays of scattered light are limited, and a plurality of rays of diffraction light is produced. The plurality of rays of diffraction light within a certain angular field of view produced by a light-limiting member interferes with each other and produces a plurality of undistorted light speckles, and forms an array of light-speckle images on the sensor. Finally, according to the array of light-speckle images, a large-area and undistorted light-speckle pattern is given. Because the light-speckle pattern is undistorted and records the three-dimensional characteristics of the object surface, the undistorted imaging apparatus can be applied to computer mice, finger guiders, smart cards, three-dimensional fingerprint identification apparatuses, a machine tool or precise manipulator positioning systems. | 08-20-2009 |
20090213388 | MEASUREMENT METHOD AND MEASUREMENT RETICLE - The present invention provides a measurement method of measuring a wavefront aberration of an optical system to be measured, the method including arranging a measurement reticle on an object plane of the optical system to be measured, forming an image of the wavefront measurement mark on an image plane of the optical system to be measured, and calculating the wavefront aberration based on a position shift amount of the image of the wavefront measurement mark from an ideal position, the image being formed on the image plane of the optical system to be measured, wherein the wavefront measurement mark includes a first mark having a longitudinal direction in a first direction, and a second mark having a longitudinal direction in a second direction perpendicular to the first direction and spaced apart from the first mark. | 08-27-2009 |
20090213389 | WAVEFRONT ABERRATION MEASURING METHOD, MASK, WAVEFRONT ABERRATION MEASURING DEVICE, EXPOSURE APPARATUS, AND DEVICE MANUFACTURING METHOD - A wavefront aberration measuring device includes a mask placed in an object plane of a to-be-tested optical system and having a pattern including a pinhole producing a spherical wave and adjoining diffraction gratings each ruled with lines oriented in a direction different from the other; an illumination optical system that illuminates an area of the mask with light emitted from a light source; a light splitter that splits the light from the pattern transmitted through the to-be-tested optical system; an image pickup unit that takes an image of interference fringes produced by the split light, the image being used in measuring wavefront aberration of the to-be-tested optical system; a detector that detects respective light quantities of respective diffracted beams from the respective illuminated diffraction gratings; and a control unit that controls alignment of the illuminated area of the mask and the pattern in accordance with a detection result. | 08-27-2009 |
20090262364 | METHOD, PHASE GRATING AND DEVICE FOR ANALYZING A WAVE SURFACE OF A LIGHT BEAM - The application relates to a method for analyzing the wave surface of a light beam from a source to the focus of a lens. The beam illuminates a sample on the analysis plane and having a defect. A diffraction grating of the plane is a conjugate of an analysis plane through a focal system. An image is formed in a plane at a distance from the grating plane and analyzed by processing means. The invention encodes this grating by a phase function resulting from the multiplication of two phase functions, a first exclusion function defining a meshing of useful zones transmitting the beam to be analyzed in the form of light pencil beams, and a second phase fundamental function which creates a phase opposition between two light pencil beams coming out of adjacent meshes of the exclusion grating. | 10-22-2009 |
20090268213 | Apparatus for measurement of the axial length of an eye - An apparatus for measuring the axial length of a human eye, the apparatus comprising a low coherence light source; a beam splitter; a fast displacement module for rapidly varying the path length within a reference arm of an interferometer; a laser directing a laser beam that is co-propagating with light from the low coherence light source into the displacement module. | 10-29-2009 |
20100002243 | APPARATUSES AND METHODS USING MEASUREMENT OF A FLARE GENERATED IN AN OPTICAL SYSTEM - The present invention provides a method including measuring a wavefront aberration of the optical system to be measured on a measurement surface, measuring a pupil transmittance distribution of the optical system determining a pupil function of the optical system based on the wavefront aberration and the pupil transmittance distribution, and performing imaging computation using the pupil function to obtain a light intensity distribution formed on an image plane of the optical system, and calculating a flare, generated in the optical system, from the light intensity distribution. | 01-07-2010 |
20100085576 | AUTO FOCUS OF A WORKPIECE USING TWO OR MORE FOCUS PARAMETERS - Provided is a method for focusing a workpiece in the Z-axis for optical metrology. The auto focusing subsystem includes a focus detector having a tilt angle, a capture range, and a plurality of sensors. A processor coupled to the focus detector is configured to utilize the plurality of focus signals measured using the focus detector to determine two or more focus parameters. The two or more focus parameters and calibration data are used to determine an initial position of the workpiece and to generate instructions to move the workpiece to a best focus position. | 04-08-2010 |
20100123902 | Method for Determining the Dynamic Range of Volume Holographic Memories - A method for measuring a saturated photorefractive index and a recording time constant to correct the precision includes measuring the diffraction efficiency as a function of time for both phase matching and phase mismatching. The saturated photorefractive index and the recording time constant are verified by substitution into a theoretical formula derived from the Coupled Wave Theory. Thus, the method allows a precise determination of the dynamic range of volume holographic memories and thus their storage capacities. The same procedure can also apply to photopolymers. | 05-20-2010 |
20100141959 | TWO GRATING LATERAL SHEARING WAVEFRONT SENSOR - Methods include simultaneously diffracting a beam in a first direction and a second direction orthogonal to the first direction to form a once-diffracted beam, where the beam comprises a wavefront shaped by a test object, simultaneously diffracting the once-diffracted beam in orthogonal directions to form a twice-diffracted beam, overlapping at least two orders of the twice-diffracted beam in each direction to form an interference pattern at a detector, the interference pattern being formed by multiple copies of the wavefront laterally sheared in the first direction and multiple copies of the wavefront laterally sheared in the second direction; and determining information about the wavefront based on the interference pattern. | 06-10-2010 |
20100149549 | WAVEFRONT ABERRATION MEASURING DEVICE AND METHOD AND WAVEFRONT ABERRATION ADJUSTING METHOD - A wavefront aberration measuring apparatus which measures an wavefront aberration of an optical system to be inspected includes a point light source which supplies a measuring light; a photodetector which has a detection surface arranged at a position optically conjugate with the point light source; a wavefront change applying section which is arranged in an optical path between the point light source and the photodetector and which applies a wavefront change to the light outcome from the optical system; and a measuring section which measures the wavefront aberration of the optical system based on an output of the photodetector and the wavefront change applied by the wavefront change applying section. It is possible to measure the wavefront aberration of the optical system with a relatively simple construction, without using the interference method. | 06-17-2010 |
20100231924 | INTEGRATED MONOLITHIC INTERFERENCE DETECTION DEVICE - The invention relates to a device ( | 09-16-2010 |
20100238457 | INHALER ADAPTOR FOR A LASER DIFFRACTION APPARATUS AND METHOD FOR MEASURING PARTICLE SIZE DISTRIBUTION - The present disclosure relates to an improved device and methods for adapting to a laser diffraction apparatus used for measuring particle size distribution and density of the plume of a powder composition emitted from a dry powder inhaler. | 09-23-2010 |
20100245841 | Cylindrical grating rotation sensor - Disclosed is a Rotation sensor with a light source, a light detector, an internal part having a first lateral surface, which is globally cylindrical and convex, and an external part having a second lateral surface which is globally cylindrical and concave. The first and second lateral surfaces both have a same central axis defining a rotation axis for a relative rotation between the internal part and the external part the angle of which this rotation sensor can measure. A first grating is arranged at the first lateral surface with its grating lines parallel to the rotation axis, and a second grating is arranged at the second lateral surface with its grating lines parallel to said rotation axis. | 09-30-2010 |
20100245842 | TRANSMITTED WAVEFRONT MEASURING METHOD, REFRACTIVE-INDEX DISTRIBUTION MEASURING METHOD, METHOD OF MANUFACTURING OPTICAL ELEMENT, AND TRANSMITTED WAVEFRONT MEASURING APPARATUS - A transmitted wavefront measuring method comprises the steps of emitting light | 09-30-2010 |
20100271636 | TALBOT INTERFEROMETER, ITS ADJUSTMENT METHOD, AND MEASUREMENT METHOD - A Talbot interferometer includes a diffraction grating, an image pickup device, a moving unit configured to move at least one of the diffraction grating and the image pickup device in an optical axis direction of the test object, and a computer configured to adjust a position of the at least one of the diffraction grating and the image pickup device using the moving unit so that a Talbot condition can be met, based on a spatial frequency spectrum obtained from a plurality of interference fringes captured by the image pickup device while moving the at least one of the diffraction grating and the image pickup device using the moving unit. | 10-28-2010 |
20100309481 | Uncertainty of uncertainty - An approach to challenging the absolute nature attributed to the Heisenberg uncertainty principal in the context of data obtained from a double slit system, wherein the double slit system is applied at least once with a multiplicity of photons or particles to produce a reference interference pattern on a first screen, and applied a second time to determine where a single photon or particle impacts a second screen. Comparison of projections from each slit through the point of impact of the single photon or particle on the second screen, to the reference interference pattern on the first screen, provides insight to which slit the single photon or particle passed. | 12-09-2010 |
20100315652 | METHOD AND SYSTEM OF ADJUSTING A FIELD OF VIEW OF AN INTERFEROMETRIC IMAGING DEVICE - A method of imaging at least a part of an object. The method comprises splitting electro-magnetic radiation to first and second portions, propagating the first and second portions, spectrally dispersing the first portion toward the part and the second portion toward a reference element, combining between reflections of the spectrally dispersed first and second portions to produce an interference signal, capturing an image of the part from the interference, and adjusting at least one of a tilt of said image plane and a curvature of the image by changing a deviation between the phase of at least one spectral component of the first portion and the phase of at least one spectral component of the second portion. | 12-16-2010 |
20110058180 | Compensated MEMS FTIR Spectrometer Architecture - A Micro Electro-Mechanical System (MEMS) spectrometer architecture compensates for verticality and dispersion problems using balancing interfaces. A MEMS spectrometer/interferometer includes a beam splitter formed on a first surface of a first medium at an interface between the first medium and a second medium, a first mirror formed on a second surface of the first medium, a second mirror formed on a third surface of the first medium and balancing interfaces designed to minimize both a difference in tilt angles between the surfaces and a difference in phase errors between beams reflected from the first and second mirrors. | 03-10-2011 |
20110063623 | ON-CHIP PHASE MICROSCOPE/BEAM PROFILER BASED ON DIFFERENTIAL INTERFERENCE CONTRAST AND/OR SURFACE PLASMON ASSISTED INTERFERENCE - A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface wave assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector. | 03-17-2011 |
20110116101 | LASER SELF-MIXING MEASURING DEVICE - A laser self-mixing measuring device is provided, comprising a laser with a laser cavity and a surface arranged along the optical path of the laser beam which redirects incident laser light back into the laser cavity. The surface comprises a periodic structure which diffracts the laser light into partial beams. | 05-19-2011 |
20110149298 | SPATIAL WAVEFRONT ANALYSIS AND 3D MEASUREMENT - A method of wavefront ( | 06-23-2011 |
20110176144 | Polarization Based Delay Line Interferometer - This invention provides a compact delay-line interferometer that can be used in Differential Phase Shift Keying (DPSK) and Differential Quardratic Phase Shift Keying (DQPSK) demodulators. The delay-line interferometer is based on polarization components including beam shifter, beam splitter and wave plates. The realized demodulators can be used as either discrete components or integrated with balanced detectors. Time delay generated in the interferometer can be controlled with a phase shifter, using either thermal, piezoelectric, mechanical of electrical means. This application claims priority to US Provisional Patent Application Ser. No. 61/238,687, filed Sep. 1, 2009, titled “Polarization Based Interferometer.” This application also claims priority to US Provisional Patent Application Ser. No. 61/295,766, filed Jan. 18, 2010, titled “Delay-Line-Interferometer for Integration with Balanced Receivers.” | 07-21-2011 |
20110199618 | Systems and Methods for Optically Generated Trigger Multiplication - Systems and methods for providing trigger signals in an optical interrogator, wherein multiple triggers are generated within each period of a varying reference signal, and wherein the triggers are evenly spaced according to the wavenumber of the reference signal. In one embodiment, an optical frequency domain reflectometry system provides a laser beam to a reference interferometer to produce a reference signal. This signal is passed through a 4×4 optical coupler which splits the signal into a first signal and a second signal that is 90 degrees out of phase with the first signal. These signals are converted to electrical signals, and a trigger unit generates triggers at points at which the two electrical signals have zero-crossings, and at which the magnitudes of the signals are equal. The resulting triggers remain evenly spaced within the period of the reference signals, even when the period is changed. | 08-18-2011 |
20110249272 | OPTICAL INSTRUMENT FOR TESTING OPTICAL SYSTEMS AND SAMPLES - The present invention is related with the optical instrument such as interferometer for testing the optical systems and samples whereas the optical instrument comprises the laser ( | 10-13-2011 |
20120026509 | ON-CHIP PHASE MICROSCOPE/BEAM PROFILER BASED ON DIFFERENTIAL INTERFERENCE CONTRAST AND/OR SURFACE PLASMON ASSISTED INTERFERENCE - A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface wave assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector. | 02-02-2012 |
20120086949 | Tunable And Switchable Multilayer Optical Devices - A multilayer optical device includes an arrangement, on a substrate, of a first layer, a second layer, and a space therebetween. The second layer is a thin-film. The arrangement of the first and second layers and the space therebetween produces transmitted, reflected, or dispersed spectrally modified electromagnetic energy from electromagnetic energy incident upon the arrangement. An optical function of the device is dependent at least in part on interference effects. An optical detector system includes a similar multilayer optical device. The space within the device is in fluid communication with structures for receiving a fluid such that the device operates in a first or second mode depending on absence or presence of the fluid within the space. The system includes a detector for receiving the modified electromagnetic energy, and a controller in fluid communication with the space that establishes the absence or presence of the fluid in the space. | 04-12-2012 |
20120099115 | INTERFERENCE OBJECTIVE LENS UNIT AND LIGHT-INTERFERENCE MEASURING APPARATUS USING THEREOF - Disclosed is an interference objective lens unit, comprising: an objective lens; a beam splitter that splits the light transmitted through the objective lens into a reference optical path in which a reference mirror is provided and a measuring optical path in which the measuring object is placed, and that superposes the split lights to output interference light; a first holder that holds the objective lens and that is formed by material having a first linear expansion coefficient; and a second holder that holds the reference mirror and that is formed by material having a second linear expansion coefficient different from the first linear expansion coefficient, wherein when a usage environment temperature changes, a difference in the linear expansion coefficients between the first holder and the second holder corrects an optical path difference between the reference optical path and the measuring optical path. | 04-26-2012 |
20120120411 | INTERFEROMETER WITH A VIRTUAL REFERENCE SURFACE - An imaging interferometer includes optics defining an interferometric cavity, in which the optics include a first beam-splitting optic positioned to separate an input beam into a test beam and a reference beam, a second beam-splitting optic positioned to transmit the test beam to the test surface, receive the test beam back from the test surface, and thereafter recombine the test beam with the reference beam, and a third optic positioned to direct the reference beam from the first optic to the second optic. The interferometric cavity defines a virtual reference surface positioned along a path for the reference beam between the second and third optics. The interferometer also includes an imaging channel positioned to receive the recombined test and reference beams, where the imaging channel includes an imaging detector, and at least one imaging element configured to image the test surface and the virtual reference surface onto the detector. | 05-17-2012 |
20120140242 | Circular common-path point diffraction interference wavefront sensor - A circular common-path point diffraction interference wavefront sensor includes an optical matching system, a beam-splitter, a first reflection mirror, a second reflection mirror, a first Fourier lens, a second Fourier lens, a charge-coupled device (CCD) detector, a computer system, and a two-pinhole mask having a reference pinhole and a testing window and placed at a confocal plane of the first Fourier lens and the second Fourier lens. A testing beam is divided into two beams through the beam-splitter. One beam makes the pinhole diffraction by the reference pinhole, thereby producing the approximately ideal plane wave as the reference wave. Another beam passes through the testing window almost without any attenuation as the signal wave. The spatially linear carrier frequency is introduced by adjusting the tilt angle of the beam-splitter. The present invention is adapted for all kinds of dynamic and static detection field of wavefront phase. | 06-07-2012 |
20120188556 | IMAGING APPARATUS AND IMAGING METHOD - An imaging apparatus includes a diffraction grating configured to produce an interference pattern by diffracting diverging light from a light source, an absorption grating configured to block part of the interference pattern, a detector configured to detect light transmitted through the absorption grating, and a moving unit configured to move the diffraction grating and the absorption grating. The moving unit causes relative movement of the interference pattern and the absorption grating by moving the diffraction grating and the absorption grating such that the diffraction grating and the absorption grating are not moved relative to each other. | 07-26-2012 |
20120250032 | GRATING-ENHANCED OPTICAL IMAGING - Systems, methods and devices are implemented for optical imaging. In one embodiment of the present disclosure, an optical imaging apparatus utilizes a laser-based coherent light source, and an optical device to pass grated light along an illumination direction from the laser-based coherent light source toward an object. Additionally, an illumination modulator is provided for changing angles at which the light, moving toward the object plane, reaches the object plane, and the light reaches the object plane at different angles. Further, the apparatus can include circuitry to process image-based data in response to and based on the light reaching the object plane at different angles for a user-viewable image of an object in proximity of the object plane. | 10-04-2012 |
20120300219 | METHOD AND APPARATUS INCORPORATING AN OPTICAL HOMODYNE INTO A SELF DIFFRACTION DENSITOMETER - A method and apparatus incorporating an optical homodyne into a self-diffraction densitometer is disclosed. The method may include splitting a laser beam into four beams by passing the laser beam through a plurality of beam splitters, passing three beams of the four beams through a lens that focuses the three beams to minimum diffraction limited waist diameter and brings them to convergence at a convergence zone containing an analyte, generating a reference beam by passing a fourth beam of the four beams through an optical phase modulator, wherein if a medium within the convergence zone absorbs energy at a wavelength of the laser beam, a thermal representation of an interference pattern forms and spatial modulation of temperature results in a spatial modulation of refractive index, whereby a diffracted beam from energy of the three beams is produced into a propagation path of the reference beam, and passing the reference beam through the lens and the convergence zone such that the reference beam is coincident with the diffracted beam, wherein the reference beam and diffracted beams cyclically go in and out of relative phase and impinge on an optical detector. | 11-29-2012 |
20130182264 | Projection Exposure Tool for Microlithography and Method for Microlithographic Exposure - A projection exposure tool for microlithography for exposing a substrate is disclosed. The tool includes a projection objective. The tool also includes an optical measuring apparatus for determining a surface topography of the substrate before the substrate is exposed. The measuring apparatus has a measuring beam path which extends outside of the projection objective. The measuring apparatus is a wavefront measuring apparatus configured to determine topography measurement values simultaneously at a number of points on the substrate surface. | 07-18-2013 |
20140016137 | Method and System for Reconstructing Optical Properties of Diffracting Objects Immersed in a Liquid Medium - A method for reconstructing optical properties of a diffracting object immersed in a liquid medium using a reconstruction system that comprises a spatially coherent light source and a matrix photodetector, wherein the liquid medium and the matrix photodetector are separated by a distance along a vertical direction. The method comprises illuminating the liquid medium, measuring (with the matrix photodetector) an intensity of a diffraction pattern transmitted by the illuminated medium along a vertical direction, and reconstructing the optical properties of the diffracting object at a reconstruction height according to a reconstruction algorithm from the measured intensity, wherein the reconstruction height has a value less than that of the distance between the medium and the matrix photodetector along the vertical direction. | 01-16-2014 |
20140192365 | SPATIAL SPLITTING-BASED OPTICAL MEMS INTERFEROMETERS - A spatial splitting-based optical Micro Electro-Mechanical Systems (MEMS) Interferometer includes a spatial splitter for spatially splitting an input beam into two interferometer beams and a spatial combiner for spatially combining the two interferometer beams. A MEMS moveable mirror is provided to produce an optical path difference between the first interferometer beam and the second interferometer beam. | 07-10-2014 |
20140192366 | EXPOSURE CONDITION DETERMINING METHOD AND SURFACE INSPECTION APPARATUS - There is provided an exposure condition determining method for determining an exposure condition for an exposure-objective substrate having a plurality of semiconductor pattern features formed by predetermined exposure on a surface thereon, the method including, irradiating an illumination light onto a surface of a substrate, which has the pattern features, detecting a diffracted light from the plurality of semiconductor pattern features of the substrate irradiated with the illumination light, and determining the exposure condition based on a variation in brightness of the detected diffracted light. | 07-10-2014 |
20150146214 | OPTICAL PERFORMANCE MEASUREMENT APPARATUS OF TEST OPTICAL ELEMENT AND ITS CONTROL UNIT - A measuring apparatus measures an optical performance of a test optical element and includes a diffraction grating configured to emit diffracted light, an image sensor configured to capture an interference pattern formed by the diffracted light, and a controller configured to move the at least one of the diffraction grating and the image sensor in an optical axis direction, to capture a plurality of interference patterns before and after movements, and to calculate a light-condensing position based on a spatial frequency of a plurality of interference patterns and a moving amount. | 05-28-2015 |
20150300885 | METHOD AND APPARATUS FOR WAVEFRONT SENSING - A method of measuring characteristics of a wavefront of an incident beam includes obtaining an interferogram associated with the incident beam passing through a transmission mask and Fourier transforming the interferogram to provide a frequency domain interferogram. The method also includes selecting a subset of harmonics from the frequency domain interferogram, individually inverse Fourier transforming each of the subset of harmonics to provide a set of spatial domain harmonics, and extracting a phase profile from each of the set of spatial domain harmonics. The method further includes removing phase discontinuities in the phase profile, rotating the phase profile, and reconstructing a phase front of the wavefront of the incident beam. | 10-22-2015 |
20160252392 | PHASE STEP DIFFRACTOMETER | 09-01-2016 |