Abstract: An optical detection system and a laser providing module without using an optical fiber thereof are provided. The optical detection system includes a carrier module, a laser light providing module, and an electrical detection module. The carrier module is configured to carry a plurality of photodiodes. The laser light providing module is disposed above the carrier module. The electrical detection module is adjacent to the carrier module. The laser light providing module is configured to convert a laser light source into a plurality of laser light beams, thereby simultaneously and respectively exciting two corresponding ones of the photodiodes. The electrical detection module is configured to simultaneously and electrically contact the corresponding photodiodes so as to obtain an electrical signal generated by each of the photodiodes.

Abstract: A physiological detection system including a light source module, a photo sensor and a processor is provided. The light source module is configured to provide light to illuminate a skin region. The photo sensor is configured to detect emergent light passing the skin region with at least one signal source parameter and output an image signal. The processor is configured to calculate a confident level according to the image signal to accordingly adjust the at least one signal source parameter.

Abstract: Provided is a polarization imaging unit that acquires a polarization image using a lens. In a parameter storage unit of an information processing unit, parameters related to a change in polarization state due to the lens which are estimated in advance from polarization state information acquired by imaging a light source in a predetermined polarization state using the lens and polarization state information indicating the polarization state of the light source, for example, change parameters indicating the change in polarization state due to the lens or correction parameters for correcting the change in polarization state due to the lens are stored. A polarization state correction unit of the information processing unit corrects the change in polarization state due to the lens, using the parameters stored in advance in the parameter storage unit.

Abstract: An oxygen saturation calculating unit calculates, based on an observation image, an oxygen saturation included in the observation target. A reliability calculating unit calculates, based on the observation image, reliability regarding the biological information. A reference value processing unit sets, for a measurement value indicative of the biological information of a measurement target in the observation target, a reference value serving as a reference for the biological information by using the reliability. A difference image generating unit calculates a difference value between the measurement value and the reference value and generates, based on the difference value, a difference image.

Abstract: A pixelated color mask is combined with a pixelated polarization mask in dynamic interferometry. The color mask includes a wavelength-selective bandpass filter placed in front of each camera pixel such that each set of contiguous four camera pixels is covered by two green bandpass filters, a red bandpass filter, and a blue bandpass filter. The pixelated phase mask is coupled to the color filters such that one polarization filter covers one set of color filters. At least three polarization filters are used to calculate phase. In addition, the color signals can be used, for example, to encode the motion of the interferometer, to provide very high speed autofocus or tip/tilt feedback, to create a color image of the object being measured, to automatically focus the system at different positions for different measurements conducted with different color sources, and to perform heterodyne interferometry with a single, vibration-immune measurement.

Abstract: A microscope comprising a coherent light source producing a coherent light beam, a light beam guide system comprising a beam splitter configured to split the coherent light beam into a reference beam and a sample illumination beam, a sample holder configured to hold a sample to be observed, a sample illumination device configured to direct the sample illumination beam through the sample and into a microscope objective, a beam reuniter configured to reunite the reference beam and sample illumination beam after passage of the sample illumination beam through the sample to be observed, and a light sensing system configured to capture at least phase and intensity values of the coherent light beam downstream of the beam reuniter.

Abstract: A method and a device for characterizing the surface shape of an optical element. In the method, in at least one interferogram measurement carried out by an interferometric test arrangement, a test wave reflected at the optical element is caused to be superimposed with a reference wave not reflected at the optical element. In this case, the figure of the optical element is determined on the basis of at least two interferogram measurements using electromagnetic radiation having in each case linear input polarization or in each case circular input polarization, wherein the input polarizations for the two interferogram measurements differ from one another.

Abstract: An optical device for characterizing a workpiece combines an interferometer with a polarization rotation pellicle, installed in a stand-alone fashion in a spatial gap between the mirrors of the interferometer, and a polarization based phase-shift sensor.

Abstract: The present inventive concepts relate to an inspection apparatus that snapshots an interference image pattern having a high spatial carrier frequency produced from a one-piece off-axis polarimetric interferometer and that precisely and promptly measures a Stokes vector including spatial polarimetric information. The inspection apparatus dynamically measure in real-time a two-dimensional polarization information without employing a two-dimensional scanner.

Abstract: A method for conducting optical measurement using a full Mueller matrix ellipsometer, which belongs to the technical field of optical measurements. The optical measurement method comprises: constructing an experimental optical path of a full Mueller matrix ellipsometer; conducting complete regression calibration on the full Mueller matrix ellipsometer; placing a sample to be measured on a sample platform, and obtaining an experimental Fourier coefficient of the sample to be measured; and according to the experimental Fourier coefficient of the sample to be measured, obtaining information about the sample to be measured.

Abstract: Described herein are apparatus and methods used to process a substrate in a chamber, in particular to position a non-round substrate in a holding chamber or a processing chamber. Further described herein are a 3D mapping device that is configured to measure the surface profile of a non-round substrate and a position of the substrate on the robot arm.

Abstract: A three-dimension position tracking system is presented. The system includes transmitters and receivers. A transmitter scans continuous or pulsed coherent light beams across a target. The receiver detects the reflected beams. The system recursively determines the location of the target, as a function of time, via triangulation and observation of the time-of-flight of the incoming and outgoing beams. The transmitter includes ultra-fast scanning optics to scan the receiver's field-of-view. The receiver includes arrays of ultra-fast photosensitive pixels. The system determines the angles of the incoming beams based on the line-of-sight of the triggered pixels. By observing the incoming angles and correlating timestamps associated with the outgoing and incoming beams, the system accurately, and in near real-time, determines the location of the target.

Abstract: An optical detection method and system are provided. Sample light is delivered into an anatomical structure having a target voxel, whereby a portion of the sample light passing through the target voxel is scattered by the anatomical structure as signal light, and another portion of the sample light not passing through the target voxel is scattered by the anatomical structure as background light that is combined with the signal light to create a sample light pattern. The sample light pattern and the reference light having an M number of different phases are concurrently combined to respectively generate an M number of interference light patterns. The M number of interference light patterns are detected. M pluralities of values representative of spatial components of the respective M number of interference light patterns are generated, and a physiologically-dependent optical parameter of the target voxel is determined based on the M pluralities of values.

Abstract: An optical phase profilometry system includes a first operative coaxial camera-projector pair aligned at a first angle relative to a target surface that projects a first illumination on the target surface and a second operative coaxial camera-projector pair aligned at a second angle relative to the target surface that projects a second illumination on the target surface. Wherein the first and second angles are equal and opposite to one another relative to the target surface such that the second operative coaxial camera-projector pair is configured to capture a first reflection from the first illumination and the first operative coaxial camera-projector pair is configured to capture a second reflection from the second illumination. The optical phase profilometry system further includes a controller configured to, based on the captured first and second reflections, generate a first and second estimation of the target surface and combine them to generate a dimensional profile of the target surface.

Abstract: The present invention relates to a method comprising reception of an incident electromagnetic wave (9) by a diffractive element (2) and conversion of this incident electromagnetic wave (9) into a diffracted electromagnetic wave (10) by the diffractive element (2); reception of the diffracted electromagnetic wave (10) by a matrix-array sensor (4) comprising a matrix-array of pixels that are aligned along one or two axes of pixel alignment (13, 14). The method comprises a plurality of acquisitions, by the matrix-array sensor (4), of a signal of the diffracted electromagnetic wave (10) corresponding to a plurality of relative positions between the diffractive element (2) and the matrix-array sensor (4). The invention also relates to a device (1) implementing this method.

Abstract: An inspection system may include a controller coupled to a differential interference contrast imaging tool for generating images of a sample based on illumination with two sheared illumination beams. The controller may determine a first defect-induced phase shift based on a first set of images of a defect on the sample with a first selected illumination spectrum and two or more selected induced phase differences between the two sheared illumination beams, determine a second defect-induced phase shift based a second set of images of the defect with a second selected illumination spectrum and two or more selected induced phase differences between the two sheared illumination beams, and classify the defect as a metal or a non-metal based on a comparison of the first phase shift to the second phase shift.

Abstract: An illumination apparatus generates an interference fringe. An input arm receives an input light beam from a light source. A splitter splits the input light beam that has passed through the input arm into a first output arm and a second output arm. A phase modulator changes a phase difference between the output light beams of the first output arm and the second output arm. A phase detector detects the phase difference between output light beams respectively output from the first output arm and the second output arm based on a return light beam generated by combining a first reflected light beam and a second reflected light beam respectively reflected by ends of the first output arm and the second output arm.

Abstract: A system includes a light source configured to selectively output light. An optical objective is configured to couple the output light from the light source to a sample under measurement when present, and direct reflected light from the sample. A controller is configured to automatically control a color of the output light and a vertical position of the optical objective relative to the sample. The color of the light is selected from multiple colors. The vertical position includes a range of vertical positions scanned by the objective. A detector is configured to receive the reflected light and to detect focus, and output data representing a surface profile of the sample. The output data includes color images of the surface profile.

Abstract: Described herein are apparatuses for dental scanning and components of apparatuses for dental scanning. A component of a dental scanning apparatus may include a beam splitter, a transparency and an image sensor. The component may have a first surface and a second surface. The transparency may be affixed to the first surface of the beam splitter, and may comprise a spatial pattern disposed thereon and be configured to be illuminated by a light source of the dental scanning apparatus. The image sensor may be affixed to the second surface of the beam splitter, wherein as a result of the transparency being affixed to the first surface of the beam splitter and the image sensor being affixed to the second surface of the beam splitter, the image sensor maintains a stable relative position to the spatial pattern of the transparency.

Abstract: Provided are systems and methods for imaging with compensation functions. An imaging device comprises a plurality of light source sets, of which two or more light source sets emit light of a same specific spectral range to compensate intensity differences among different spectral ranges. The imaging device can be integrated with a mobile device. A method comprises a subtraction procedure to compensate ambient light effect, a normalization procedure to compensate incidence angle effect, a 3D reconstruction procedure to compensate distance effect, or any combination of these procedures. The method is performed at an imaging device comprising a controller. At least one program is non-transiently stored in the controller and executable by the controller.

Abstract: A Mirau interference objective includes an objective lens and a splitter element arranged between the objective lens and an object to be examined. The splitter element is configured to split an incident light beam into a sample beam path and a reference beam path. The objective lens is configured to focus the sample beam path on the object to be examined. A mirror element is arranged between the splitter element and the objective lens. The mirror element is configured to reflect the reference beam path. A phase shift compensating element is configured to compensate for a wavelength-dependent phase shift between the reference beam path and the sample beam path which is superposed on the reference beam path.

Abstract: An interferometer system may include a stage assembly configured to receive and secure a sample, an illumination source configured to generate an illumination beam, a half-wave plate, one or more shearing prisms to shear the illumination beam into two beamlets along a shearing direction, a reference flat disposed proximate to the sample, a detector assembly, and a controller. The controller may cause the illumination source to generate an illumination beam and sweep the illumination beam across a plurality of wavelengths, and determine both a surface height measurement and a surface slope measurement of the sample based on the illumination received by the detector assembly.

Abstract: A co-located imaging and display pixel includes an image pixel having a photosensitive element and a display pixel co-located with the image pixel. An optical transformation engine is coupled between the image pixel and the display pixel. The optical transformation engine is configured to modulate an amplitude of display light emitted by the display pixel in response to receiving an imaging signal generated by the photosensitive element of the image pixel.

Abstract: A three-dimensional form measurement device includes: an interference fringe projector that scans an interference fringe and projects one of a plurality of interference fringe patterns; an imaging device that images the subject of measurement onto which the interference fringe is projected and generates a plurality of interference fringe images corresponding to at least three different interference fringe patterns in each of a plurality of imaging conditions; and a controller that selects, for each pixel, which imaging condition should be used to compute a phase distribution image of the subject of measurement, and computes a phase of each pixel in the phase distribution image based on the pixel values in the plurality of interference fringe images corresponding to the imaging condition selected for each pixel.

Abstract: An optical system uses a multi-layered birefringent structure that receives an input beam that may be non-coherent or coherent, and produces a randomization energy from the input beam, by creating birefringent induced beam subdivisions as the beam passes through each birefringent layer, where after the beam has passed through a threshold number of birefringent layers, a randomized energy distribution is created. That randomized energy distribution is read by a photodetector and converted into a random number by a randomization processing device.

Abstract: The range of measurement in spectrally controlled interferometry (SCI) is extended by superimposing multiple modulations on the low-coherence light used for the measurement. Optimally, a spectrally controllable light source modulated sinusoidally with low spectral frequency is combined with a delay line, such as provided by a Michelson interferometer. The resulting light is injected into a Fizeau interferometer to generate localized fringes at a distance corresponding to the effect of the spectrally modulated source combined with the optical path difference produced by the delay line. The combination provides a convenient way to practice SCI with all its advantages and with a range that can be extended to the degree required for any practically foreseeable application.

Abstract: A method for measuring Z height values of a workpiece surface with a machine vision inspection system comprises illuminating a workpiece surface with structured light, collecting at least two stacks of images of the workpiece, each stack including a different X-Y position between the structured light and the workpiece surface at a corresponding Z height in each of the stacks, and determining Z values based on sets of intensity values of a pixel corresponding to the same workpiece position in the X-Y plane which are at the same Z heights. The X-Y position is changed at a slower rate than the Z height in each stack of images, and is changed either continuously during each of the at least two stacks at a slower rate than the Z shift, or fixed to a different value during each of the at least two stacks.

Abstract: An interference measurement device configured to detect a phase from an interference beam between an object beam and a reference beam, includes: a laser beam source; a splitter configured to split an emitted beam from the laser beam source into the object beam and the reference beam; an object beam optical unit configured to make only the object beam incident on a measurement object; a combination unit configured to combine the object beam and the reference beam; a phase element configured to vary mutual relationship in phase between the object beam and the reference beam; and a detector configured to detect the interference beam between the object beam and the reference beam. A signal of a spatial phase variation of the measurement object is directly operated, based on at least two measurement results of an intensity signal with the detector.

Abstract: Embodiments of the disclosure provide a metrology system. In one example, a metrology system includes a laser source adapted to transmit a light beam, a lens adapted to receive at least a portion of the light beam from the laser source, a first beam splitter positioned to receive at least the portion of the light beam passing through the lens, a first beam displacing device adapted to cause a portion of the light beam received from the beam splitter to be split into two or more sub-light beams a first recording device having a detection surface, and a first polarizer that is positioned between the first displacing device and the first recording device, wherein the first polarizer is configured to cause the two or more sub-light beams provided from the first displacing device to form an interference pattern on the detection surface of the first recording device.

Abstract: Embodiments of a shearography system may include light sources configured to produce beams of light to illuminate a test area. Each of the beams of light may include a different wavelength. A camera may be configured to obtain intensity information corresponding to reflections of the lights off of the test area. An optical shearing device may be disposed in an optical path between the light sources and the camera and the optical shearing device may be configured to provide a shearing angle.

Abstract: A generation method of a digital hologram includes steps of emitting coherent light from a coherent light source, imaging a hologram that is an interference pattern of an object beam and a reference beam due to the emission light from the light source, and setting a plurality of wavelengths of the illumination light that generates the hologram detected by the detector, and wherein the plurality of wavelength are specified by the wavelength setting step based on a magnification percentage X of a conjugate image set up by a user not to disturb visibility of an image when a real image and the conjugate image reconstructed by a predetermined calculation means relative to structures of observation targets are superimposed to a corresponding real image so that a shortest wavelength ?min and a longest wavelength ?max satisfy the expression ?max/?min?(1/X+1).

Abstract: In one aspect an imaging system includes: an illumination system including an array of light sources; an optical system including one or more lens arrays, each of the lens arrays including an array of lenses, each of the lenses in each of the one or more lens arrays in alignment with a corresponding set of light sources of the array of light sources; an imaging system including an array of image sensors, each of the image sensors in alignment with a corresponding lens or set of lenses of the one or more lens arrays, each of the image sensors configured to acquire image data based on the light received from the corresponding lens or set of lenses; a plate receiver system capable of receiving a multi-well plate including an array of wells, the plate receiver system configured to align each of the wells with a corresponding one of the image sensors; and a controller configured to control the illumination of the light sources and the acquisition of image data by the image sensors, the controller further configure

Abstract: A microscope including an imaging objective for imaging a sample on a detector and means for illuminating the sample with a light sheet in the focus plane of the imaging objective. The illumination means includes an illumination source which emits coherent light, and Bessel optics which generate at least two plane waves from the light beam and give propagation directions for the plane waves. The propagation direction of each of the plane waves encloses an acute angle with the focus plane in each instance, the magnitude of the acute angle being identical for each of the plane waves, so that the plane waves undergo constructive interference in the focus plane so that a light sheet is generated. Similarly, the illumination means can also include an optical element by which a rotationally symmetric Bessel beam is generated from the light beam for dynamic generation of a light sheet.

Abstract: An imaging apparatus comprises a lens optical system including a lens and having first through nth optical regions (n is an integer equal to or greater than 2), an image sensor including pixel groups each including first through nth pixels, an optical element array disposed between the lens optical system and the image sensor and including optical components each guiding light that has passed through the first through nth optical regions to the respective first through nth pixels in each of the pixel groups, and an optical absorption member on which light reflected by the imaging surface of the image sensor is incident. The optical absorptance of the optical absorption member is substantially uniform across the entire wavelength bands of light that passes through the first through nth optical regions and is substantially uniform across the entire optical absorption member.

Abstract: According to one aspect, the invention concerns a method for microscopy of a thick sample arranged on a sample support, with edge-illumination of the sample. The method comprises, in particular, emitting at least one illumination beam (1), forming, from the illumination beam, an illumination surface, focusing the illumination surface in the sample by means of a microscope lens (120) and deflecting the illumination surface originating from the microscope lens, in order to form a transverse illumination surface, located in a plane substantially perpendicular to the optical axis of the microscope lens.

Abstract: An optical detection method and system are provided. Sample light is delivered into an anatomical structure having a target voxel, whereby a portion of the sample light passing through the target voxel is scattered by the anatomical structure as signal light, and another portion of the sample light not passing through the target voxel is scattered by the anatomical structure as background light that is combined with the signal light to create a sample light pattern. The sample light pattern and the reference light having an M number of different phases are concurrently combined to respectively generate an M number of interference light patterns. The M number of interference light patterns are detected. M pluralities of values representative of spatial components of the respective M number of interference light patterns are generated, and a physiologically-dependent optical parameter of the target voxel is determined based on the M pluralities of values.

Abstract: A cycloidal diffraction waveplate is combined with a pixelated phase mask (PPM) sensor in a dynamic fringe-projection interferometer to obtain phase-shifted interferograms in a single snap-shot camera operation that provides the phase information required to measure test surfaces with micrometer precision. Such mode of operation enables a portable embodiment for use in environments subject to vibration. A shifting mechanism coupled to the cycloidal waveplate allows temporal out-of-phase measurements used to remove noise due to test-surface characteristics. Two or more pixels of each unit cell of the PPM are combined to create super-pixels where the sum of the phases of the pixels is a multiple of 180 degrees, so that fringes are eliminated to facilitate operator focusing. By assigning colors or cross-hatch patterns to different ranges of modulation measured at the detector, the areas of best focus within the field of view are identified quantitatively to ensure measurements under best-focus conditions.

Abstract: A light beam scanning device includes a controller device which dynamically adjusts a divergence of the beam. Divergence adjustment can include adjusting the beam divergence along one or more cross sectional axes of the beam. Beam divergence can be adjusted between consecutive scans, during a scan, etc. Beam divergence can be adjusted based on the field of view and scan rate. Beam divergence adjustment can enable dynamic adjustment of the spot size of the beam, which can enable the apparatus to adjust between scanning a wide divergence beam to detect objects in a scene and scanning a narrow divergence beam to generate detailed point clouds of the detected objects. Beam divergence adjustment can enable adjustment of reflection point intensity, enabling detection of low-reflectivity objects.

Abstract: Embodiments of the present invention provide a recognition device and an alignment system. The recognition device is configured to recognize an alignment mark on a display substrate and comprises a camera unit and a light source unit. The camera unit is configured to shoot the alignment mark, and the light source unit is configured to radiate emitted light onto the alignment mark. The recognition device further comprises a light processing unit configured to process light emitted from the light source unit so that the luminance of the light irradiated onto the alignment mark is greater than that of the light emitted from the light source unit. Through the arrangement of the light processing unit, the recognition device enables the luminance of the light irradiated onto the alignment mark to be greater than that of the light emitted from the light source unit.

Abstract: An arrangement having a birefringent component is provided for use in spatial offset measurements and analysis systems. The birefringent optical arrangement provides different directional control of the excitation signal relative to the emission signal, so that offset between an excitation and emission location on a sample can be controlled for both or only one of the excitation signal relative to the emission signal.

Abstract: A method for autofocusing in microscopic examination of a specimen located at the focus of a microscope objective uses an autofocus beam path, the autofocus beam path being directed, via a deflection device arranged on the side of the microscope objective facing away from the specimen, toward the microscope objective, and from there onto a reflective autofocus interface in the specimen region. The autofocus beam path is reflected at the autofocus interface and directed via the microscope objective and the deflection device toward an autofocus detector. The deflection device comprises two regions spaced apart from one another in a propagation direction of the autofocus beam path. Each region reflects the autofocus beam path. The autofocus detector is arranged in a plane conjugated with the microscope objective pupil to acquire an interference pattern. The focus of the microscope is adjusted as a function of the acquired interference pattern.

Abstract: Fizeau interferometers, in-flight metrology systems and methods of testing optical systems are described. Collimated or near collimated light is directed to interact with at least one diffractive focusing element of an optical system. The collimated or near collimated light is modified by the diffractive focusing element to form first diffracted light. The first diffracted light is directed to an image surface of the diffractive focusing element. A portion of light directed from the image surface is reflected by the diffractive focusing element back to the image surface as second diffracted light. The second diffracted light has a different diffraction order than the first diffracted light. The second diffracted light is detected to characterize the optical system.

Abstract: Provided is an optical tomographic device for simultaneously acquiring a plurality of tomographic images at a same position in a subject without narrowing a depthwise measurement range. A measurement light generator generates at least two measurement lights with different optical path lengths, superimposes the at least two measurement lights, radiates the resultant light to a subject, and splits reflected light reflected from the subject into at least two reflected lights. A reference light generator generates at least two reference lights with different optical path lengths. An interfering light generator combines the at least two reflected lights and the at least two reference lights having corresponding different optical path lengths, to generate at least two interfering lights. An interfering light detector detects the at least two interfering lights independently by at least two interfering light detectors.

Abstract: An imaging apparatus includes an imaging optical system having an exit pupil and an image sensor having pixels including first and second pixels. Each pixel has high and low sensitivity light receiving sections and a pupil divider. Each of the first pixels is arranged near one of the second pixels. The pupil divider guides light from a part of the exit pupil of the imaging optical system to the high or low sensitivity light receiving section in a first pixel and guides light from another part of the exit pupil to the high or low sensitivity light receiving section in the neighboring second pixel. The positional relation between the high and low sensitivity light receiving sections relative to the center in a pixel is mutually inverted in the pupil dividing direction between a first pixel and the neighboring second pixel.

Abstract: Polarization based interferometric methods suffer from errors caused by the internal instrument birefringence. Disclosed herein are methods for using dual interferometric measurements allow separating the influence of instrument errors (e.g., due to geometry and birefringence errors) and the measured part. The interferometric system error in an interferometry system having two light sources orthogonally polarized with respect to each other wherein each light source reflects from a reference surface and a test surface, creating four reflected beams (Wr, Vr, Wt, Vt), may be determined by performing a first interference measurement (M1) from Wr-Vt. A second interference measurement (M2) from Wt-Vr is performed and a third measurement (M3), indicative of the interferometric system error, is calculated by averaging the first and second measurements ([M1+M2]/2).

Abstract: The present invention relates to an optical phase measuring method and an optical phase measuring device which can measure phase information contained in an object beam with high accuracy. Intensity distributions of a test object beam, a first reference beam and a first hologram made from the object beam and the first reference beam are detected by the first light intensity detection section. Intensity distributions of the test object beam, a second reference beam and a second hologram made from the object beam and the second reference beam are detected in the second light intensity detection section. Phase information contained in the object beam is computed on the basis of the intensity distributions detected in the first light intensity detection section and the intensity distributions detected in the second light intensity detection section.

Abstract: Certain aspects pertain to aperture-scanning Fourier ptychographic imaging devices comprising an aperture scanner that can generate an aperture at different locations at an intermediate plane of an optical arrangement, and a detector that can acquire lower resolution intensity images for different aperture locations, and wherein a higher resolution complex image may be constructed by iteratively updating regions in Fourier space with the acquired lower resolution images.

Abstract: A practical method for greatly enhancing the strength of the modulated signal from laser probing of IC's is described. An IC device under test (DUT) is scanned with two spatially separated laser beams. The output from a single laser source is split into two separate components with each focused on different areas of the DUT. The separation between the beams and their intensity is adjustable to maximize the strength of the modulated return signal. Typically a NIR laser is used with flip-chip IC devices to account for the band-gap (transmission) characteristics of the substrate material. Upon reflection from the DUT, the reflected beams are recombined to interfere with one another. The phase difference of the two beams is adjustable to gain maximum interference. This signal is then processed to obtain the waveforms that correspond to the actions of the active gates and nodes as the chip is electronically cycled through its prescribed test loop.

Abstract: A position measuring device includes a light emitter, an image capturer, a first beam splitter, a first light receiver, a second light receiver, a calculator, and a controller. The first light receiver receives light that propagates along a first optical axis toward the light emitter and is reflected by the first beam splitter, and outputs a first signal. The second light receiver outputs a second signal corresponding to an intensity of light propagating along a second optical axis toward the image capturer. The controller controls the intensity of the laser light based on the second signal when a difference between the first signal and the second signal is smaller than a predetermined threshold, and performs control so that the laser light has a predetermined intensity when the difference between the first signal and the second signal is equal to or greater than the threshold.

Abstract: A reflective optical element includes a body with a first reflective surface of a high precision geometrical form, which can be used for reflecting light in a wavelength range less than 50 nm in an EUV-lithographic projection exposure system. The body includes first and a second non-reflecting surfaces. Further, the body includes a single connection area formed on the first non-reflecting surface with at least one fixation surface inside the connection area for fixing the entire optical element directly or indirectly to at least one bearing surface of a bearing element. The second non-reflecting surface is different from the single connection area formed on the first non-reflective surface. The second non-reflecting surface at least partly surrounds the single connection area. At least one stress relief recess is formed into the body. The stress relief recess at least partly separates the first non-reflective surface from the second non-reflecting surface.