Abstract: A method using fringe projection to describe the three-dimensional profile of a specular object is presented and has steps of: providing a diffraction grating formed by exposing and developing a hologram and having at least two sets of interference fringes; guiding a conjugate of the reference light generated from a conjugate light source to pass through the diffraction grating, in order to generate a real image with a long depth of field, a wide convergent angle, and a sinusoidal distribution light intensity; projecting this real image onto an inspected specular object; using an image capture device to capture the intensity distribution of the real image on the inspected specular object so as to obtain an image signal; and using an image processor to analyze the image signal so as to identify the profile of the inspected specular object.

Abstract: Apparatus include a test cell body having a first exterior surface, a second exterior surface, a cavity extending between the first exterior surface and the second exterior surface, and a first textured wetted plate and a second textured wetted plate disposed within the cavity. A fluid flow gap is defined between the first textured wetted plate and the second textured wetted plate. An illuminator is disposed between the second textured wetted plate and the second exterior surface, and a viewing window formed within the first exterior surface. The first textured wetted plate and the second textured wetted plate may be transparent.

Abstract: A noise reduction device capable of reducing noise over a wide frequency range and a detection apparatus including the same are provided. The noise reduction device includes a splitting unit configured to split pulsed light generated in a first period into three or more pulsed light beams, a delaying unit configured to provide the three or more pulsed light beams with different delay times, and a combining unit configured to combine the three or more pulsed light beams. Among the three or more pulsed light beams, two pulsed light beams whose delay times provided by the delaying unit are closest to each other are configured such that a difference between their delay times is equal to the first period.

Abstract: In one aspect, an apparatus for determining a property of a fluid is disclosed that in one embodiment may include a transparent member having an axis and a first end substantially perpendicular to the axis and a second end having an outer surface at a first angle to the axis, a light source directing light at the first end, a detector placed spaced from the second end, the space between the second end and the detector containing a fluid, wherein the detector detects light exiting from the outer surface at a second angle to the axis and passing through the fluid, and a controller for determining the second angle from the light detected by the detector. A processor determines the bulk fluid refractive index from the light detected by the detector and a property of the fluid therefrom.

Abstract: In an optical position measuring device for detecting the relative position of a first measuring standard and a second measuring standard, movable relative to each other along at least one measuring direction, at a splitting grating, a beam bundle emitted by a light source is split up into at least two partial beam bundles. When passing through scanning beam paths, the partial beam bundles undergo different polarization-optical effects. After the differently polarized partial beam bundles are recombined at a combination grating, a plurality of phase-displaced, displacement-dependent scanning signals is able to be generated from the resulting beam bundle. No polarization-optical components are arranged in the scanning beam paths of the partial beam bundles between the splitting and recombination.

Abstract: Provided is a shape measuring apparatus that is capable of suppressing adverse effects on measurement accuracy. A probe is provided with an illumination optical system that irradiates an object with light and an image capturing device that detects light reflected by the object. A rotation mechanism that rotates the probe is disposed at a position distanced from a rotation axis line. Attitude of the probe) relative to the object can be changed in accordance with the rotation of the probe. Signals detected by the image capturing device are calculated by a shape information acquisition unit.

Abstract: An optical coherence tomography (OCT) measurement system for precision measurement of a translucent sample is provided.

Abstract: A method for reviewing a defect including a light capturing step that illuminates a sample with light under plural optical conditions, while varying only at least one of illumination conditions, sample conditions, or detection conditions, and detects plural lights scattering from the sample; a signal obtaining step that obtains plural signals based on the lights detected; and a processing step that discriminates a defect from noise according to a waveform characteristic quantity, an image characteristic quantity, or a value characteristic quantity created using the signals and derives the coordinates of defect.

Abstract: An analysis apparatus is provided with: a light emitting part, a light dispersing part, a light detecting part, a storage unit, and a control unit. The light dispersing part disperses first reflected light reflected from a food product when the food product has been irradiated with light from the light emitting part. The light detecting part: generates first detection data by detecting the first reflected light dispersed; and, when a food product sample containing known ingredients is irradiated with light from the light emitting part, generates second detection data by detecting second reflected light reflected from the food product sample and dispersed by the light dispersing part. The storage unit stores a regression formula computed using the second detection data as a parameter. The control unit estimates the ingredients contained in the food product using the first detection data and the regression formula stored in the storage unit.

Abstract: A method and system for identifying a given geometrical feature of an optical component or semi-finished ophthalmic lens blank, where an optical component is made of an organic material that can emit light at an emission wavelength ?e when being lighten at an illumination wavelength ?i different from the emission wavelength ?e, a surface of the optical component is illuminated with an incident light beam including at least light at the illumination wavelength but devoid from light at the emission wavelength, light emitted at the emission wavelength by the illuminated surface is collected to build an image of the surface, and the surface image is processed to apply metrics to compare the image with reference data specific to the given geometrical feature.

Abstract: A zeroing method and zeroing device for an optical time-domain reflectometer (OTDR) are disclosed. The zeroing method includes: before starting the optical time-domain reflectometer, when a laser device is in an off state, sending a zeroing signal; and performing zeroing processing according to the zeroing signal. In the embodiments of the present invention, the feedback zeroing can be performed on a receiving circuit by utilizing the idle time prior to a test or during the test, thus the influence of an offset voltage is reduced, and a problem of operational-amplifier zero drift also can be solved in the meantime, which improves a detectability of the OTDR, and overcomes a disadvantage that a manual zeroing method is not intelligent and a measured waveform introduced in an automatic zeroing method is bad.

Abstract: Methods and algorithms are provided, as well as new metrics for misalignment of apertures with respect to the optical axis of a metrology system. The methods comprise aligning aperture(s) to an optical axis of a scatterometry metrology tool using correction term(s) derived by minimizing an overlay variation measure calculated with respect to overlay measurements of a periodic structure. These methods result in highly sensitive misalignment metrics, which may be used in calibration stages or on the fly to align the system's apertures, and enable reducing target size due to the resulting enhanced alignment accuracy.

Abstract: A method of determining the relative concentrations of enantiomeric forms of a compound in an enantiomeric mixture includes combining the enantiomeric mixture with carbon nanotubes or graphene to form a carbon-enantiomer mixture, exposing the mixture to a monochromatic polarized light, and analyzing reflected polarized light from the mixture using a differential analyzer.

Abstract: Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first apertures based on a defect detection characteristic of each composite image.

Abstract: An inspection apparatus for simultaneous dark field (DF) and differential interference contrast (DIC) inspection includes an illumination source and a sample stage configured to secure a sample. The inspection apparatus includes a first sensor, a second sensor and an optical sub-system. The optical sub-system includes an objective, one or more optical elements arranged to direct, through the objective, illumination from the one or more illumination sources to a surface of the sample. The objective is configured to collect a signal from the surface of the sample, wherein the collected signal includes a scattering-based signal and/or a phase-based signal from the sample. The inspection apparatus includes one or more separation optical elements arranged to spatially separate the collected signal into a DF signal and a DIC signal by directing the DF signal and the DIC signal along a DF path and DIC path respectively.

Abstract: Methods and systems are provided, which pattern an illumination of a metrology target with respect to spectral ranges and/or polarizations, illuminate a metrology target by the patterned illumination, and measure radiation scattered from the target by directing, at a pupil plane, selected pupil plane pixels from a to respective single detector(s) by applying a collection pattern to the pupil plane pixels. Single detector measurements (compressive sensing) has increased light sensitivity which is utilized to pattern the illumination and further enhance the information content of detected scattered radiation with respect to predefined metrology parameters.

Abstract: The invention provides a system and method for rapid validation of identity from tissue using registered two dimensional and optical coherence tomography (OCT) scan images. The preferred embodiment provides, for a human fingerprint, validation that the surface fingerprint matches the primary fingerprint. An alternate embodiment provides validation of “aliveness” by ascertaining blood flow. Various embodiments are taught.

Abstract: A measurement device (120) includes a light director and a spatial light modulator (130). The light director is disposed to direct light to the spatial light modulator (130) and the spatial light modulator (130) is disposed to receive light from the light director and to modulate it to form an intensity pattern. An optical element is disposed to receive light which formed the intensity pattern and is arranged to magnify the intensity pattern into a measurement space. A detector (142) is disposed to detect light reflected from the measurement space.

Abstract: An optical spectrometer contains a photodiode and a straining mechanism for imposing adjustable strain on the photodiode. The spectrometer includes a measurement apparatus for measuring variation of photocurrent with strain at different values of the adjustable strain imposed by the straining mechanism. Adjusting the strain allows adjustment of the band gap Eg of the photosensitive region of the photodiode, and this determines the cut-off energy for absorption of photons. Measuring variation of photocurrent with strain at different values of the adjustable strain imposed by the straining mechanism allows study of photons within a desired energy range of the band gap energy corresponding to each strain value.

Abstract: The present disclosure provides a sunglass testing station that is useful for determining the effectiveness and desirability of a pair of sunglasses in “real world” environments. In one embodiment, the sunglass testing station comprises a base, a vertical member, and a viewing box. In other aspects, the sunglass testing station comprises a base, a handheld viewing sphere, a visual display, and interactive simulation components.