Abstract: A system for monitoring a composition includes: an electromagnetic source that emits a beam; one or more evanescent field sensing element inside a tubular structure, arranged in series along a flow direction of the composition, and configured to be in direct contact with the composition; a waveguide that directs at least a portion of the beam to the evanescent field sensing element as an incident beam; and a detector configured to obtain a spectral distribution of the fingerprint beam. The evanescent field sensing element provides partial or total internal reflection of the incident beam at an interface between the evanescent field sensing element and the composition, and the incident beam interacts with the composition to form a fingerprint beam.

Abstract: Methods for linearization of photodetector response include establishing one or more static calibration coefficients based on comparison of test photodetector response to a linear reference photodetector. In some examples, dynamic calibration coefficients are determined based on average photodetector signals. In some applications such as FTIR, linearized ratios are obtained with a single calibration coefficient.

Abstract: A spatial modulator is provided on a plane conjugate to a sample plane on which a sample is to be placed. The spatial modulator spatially modulates illumination light irradiated to the sample 2 or object light that has passed through or that has been reflected by the sample. A dark-field optical system removes the non-scattered light component of the first object light affected by the spatial light modulator so as to generate second object light. An image sensor records a hologram based on the second object light. A calculation processing apparatus combines complex amplitude information based on the modulation pattern supplied to the spatial light modulator and complex amplitude information based on the hologram with respect to the second object light so as to acquire a phase distribution originating from the sample.

Abstract: A detection method based on laser-induced breakdown spectroscopy enhanced by a two-dimensional plasma grating includes: generating a femtosecond laser pulse by a femtosecond laser, and splitting the femtosecond laser pulse into three sub-pulses by a beam splitting unit; focusing the three sub-pulses separately by a focusing unit to allow focused sub-pulses to be overlapped at an intersection in space, wherein before reaching the intersection, the three sub-pulses form two planes; synchronizing the three sub-pulses in a time domain by adjusting optical paths of the three sub-pulses in such a way that they have the same optical length and the three sub-pulses arrive at the intersection in space simultaneously and form the two-dimensional plasma grating; and exciting a sample on a stage based on the two-dimensional plasma grating to generate a plasma cluster, and acquiring a spectrum of the sample.

Abstract: Systems and methods are provided for a UV-VIS spectrophotometer, such as a UV-VIS detector unit included in a high-performance liquid chromatography system. In one example, a system for the UV-VIS detector unit may include a first light source, a signal detector, a flow path positioned intermediate the first light source and the signal detector, a second light source, and a reference detector. The first light source, the signal detector, and the flow path may be aligned along a first axis, and the second light source and the reference detector may be aligned along a second axis, different than the first axis.

Abstract: A method and apparatus for biogas extraction. The method includes obtaining a set of images that includes a field of view encompassing at least a portion of the flexible roof and a background; generating a sample region having a first end overlapping only the flexible roof and a second end overlapping only the background; determining an average pixel color of an end slice located at the first end or the second end of the sample region; determining, based on the average pixel color of the end slice of the sample region, a fill percentage of the sample region attributed to an object overlapped by the end slice; estimating an amount of inflation of the flexible roof based on the fill percentage and a correlation between fill percentages of the sample region and predetermined amounts of inflation included in calibration data; and controlling extraction of the biogas based on the estimation.

Abstract: A cost of a testing device is reduced. A structure of a testing device is simplified. A testing device capable of testing with higher accuracy is provided. A testing device (10) has a structure including a sending unit (13), a receiving unit (14), a control unit (11), and a display (15). The control unit includes a memory portion (21) and an arithmetic portion (22). The sending unit has a function of generating a pulse signal for a probe (40) to generate an ultrasonic wave (51). The receiving unit has a function of generating a first signal including a first analog data (D1) on the basis of the input single input from the probe. The memory portion has a function of storing the first analog data. The arithmetic portion has a function of generating an image signal (S0) output to the display on the basis of the first analog data stored in the memory portion. The display has a function of displaying an image based on the image signal.

Abstract: A spectrometer capable of providing information, to a measurer, necessary for determining whether a sample set to the spectrometer is a sample expected by the measurer or not before a main measurement includes a data processor and a display. The data processor calculates a preliminary spectral information of the sample based on at least n of a latest detected signal and a BKG information retained in advance, calculates and updates the preliminary spectral information based on at least n of the latest detected signal and the BKG information again, and repeats these calculations and updates. The display shows the preliminary spectral information that is calculated and updated in the preview display. The data processor starts integration of N (N>n) of the detected signal during a preview display of the preliminary spectral information, and acquires a spectral information of the sample.

Abstract: A thickness evaluation method of the cell sheet according to the invention includes tomographically imaging a cell sheet by optical coherence tomography and obtaining a thickness distribution of the cell sheet based on a result of the tomography imaging. A tomographic image corresponding to one cross section of the cell sheet is obtained by tomography imaging while scanning the light in a main scanning direction. The tomography imaging is performed in every time while moving an incident position of the light at a predetermined feed pitch in a sub-scanning direction, thereby a plurality of the tomographic images corresponding to a plurality of cross-sections are obtained. One-dimensional thickness distributions of the cell sheet in the corresponding cross-sections are obtained based on each of the plurality of tomographic images, and a two-dimensional thickness distribution of the cell sheet is obtained by interpolating the one-dimensional thickness distributions.

Abstract: A processer of an optical module is configured to control a voltage signal having a frequency for causing a movable mirror to resonate, and perform an intensity acquisition process. The intensity acquisition process is a process of acquiring a measurement light intensity of the interference light of the measurement light M times at a first time interval based on the frequency in each of a plurality of cycles among P cycles continuous in the voltage signal, acquiring an addition value of a plurality of the measurement light intensities mutually corresponding for the same number of times, acquiring a laser light intensity of the interference light of the laser light N times at a second time interval based on the frequency in each of the plurality of cycles, and acquiring an addition value of a plurality of the laser light intensities mutually corresponding for the same number of times.

Abstract: In a general aspect, radio frequency (RF) electromagnetic radiation can be detected using vapor cell sensors. In some aspects, a system includes a laser system that is configured to generate laser signals that comprise first and second laser signals. The system also includes an optical comb generator and a vapor cell sensor. The optical comb generator is configured to generate a comb spectrum based on the first laser signal. The comb spectrum includes comb lines at respective comb frequencies. The vapor cell sensor contains a vapor and is configured to generate an optical spectrum based on interactions of the vapor with the comb spectrum and the second laser signal. The system also includes an optical detector that is configured to detect the property of the optical spectrum at one or more of the comb frequencies.

Abstract: A method of providing optical coherence tomography (OCT) imaging may comprise using an on-chip frequency comb source interfaced with an OCT system by a circulator as an imaging source and reconstructing OCT images from resulting spectral data from target tissue illuminated by the imaging source.

Abstract: A system for performing spectroscopy, including a first frequency comb source outputting first electromagnetic radiation comprising a first frequency comb centered at a first wavelength and having a first repetition rate; a second frequency comb source outputting a second electromagnetic radiation comprising a second frequency comb centered at a second wavelength and having a second repetition rate; a nonlinear device positioned to receive the first frequency comb and the second frequency comb, wherein the nonlinear device interacts the first frequency comb and the second frequency comb through sum frequency generation or difference frequency generation so as to generate an output electromagnetic radiation; and a detection system outputting a signal in response to detecting an interference of the output electromagnetic radiation with a third electromagnetic radiation, the signal comprising information used for determining a spectrum of at least the first frequency comb or the second frequency comb.

Abstract: Disclosed is a method for measuring the absorbance of light of a substance in a solution in a measuring cell (23; 223?), said method comprising the steps of: transmitting (S1) a first light beam (27; 27?) from a light source (25; 25?) towards a beam splitter (29; 29?); dividing (S3) the first light beam (27; 27?) into a signal light ray (31; 31?) and a reference light ray (33; 33?) by the beam splitter (29; 29?); modulating (S5) the signal light ray (31; 31?); modulating the reference light ray (33; 33?); providing (S9) the measuring cell (23; 23?) such that the signal light ray (31; 31?) passes through the measuring cell; detecting (S11) a signal in a detector (39; 39?), which signal is the combined signal intensity of the signal light ray (31; 31?) and the reference light ray (33; 33?) detected by the detector (39; 39?); performing synchronous detection (S15) of the detected signal in order to reconstruct the intensities of the signal light ray (31; 31?) and the reference light ray (33; 33?) from the combin

Abstract: This defect inspection apparatus (100) is provided with an excitation unit (1), a laser illumination unit (2), an interference unit (3), an imaging unit (35), and a control unit (4) for generating a moving image (61) related to the propagation of an elastic wave of an inspection target (7). The control unit is configured to perform control to display an identified measurement inappropriate region (81) in such a manner as to be distinguishable from a measurement appropriate region (82) in which the vibration state has been correctly acquired in the moving image (61).

Abstract: Apparatus and methods are presented for enhancing the acquisition speed or performance of Fourier domain optical coherence tomography. In preferred embodiments a plurality of wavelength combs containing interleaved selections of wavelengths from a multi-wavelength optical source are generated and projected onto a sample. In certain embodiments the wavelength combs are projected simultaneously onto a plurality of regions of the sample, while in other embodiments the wavelength combs are projected sequentially onto the sample. Light in the wavelength combs reflected or scattered from the sample is detected in a single frame of a sensor array, and the detected light processed to obtain a tomographic profile of the sample. In preferred embodiments the wavelength comb generator comprises a wavelength interleaver in the form of a retro-reflective prism array for imparting different displacements to different selections of wavelengths from the optical source.

Abstract: System include an ultrasonic transducer configured to couple to a nondestructive testing (NDT) sample and configured to produce and direct an ultrasonic probe wave at a selected frequency into a subsurface region of the NDT sample, a 3D laser scanning vibrometer configured to direct a detection beam in a scan area on a surface of the NDT sample and to receive a return beam from the scan area, and to detect, based on the return beam, a 3D motion of the surface across a wideband frequency range, and a processor, and a memory configured with instructions that, when executed by the processor, cause the processor to produce sub-surface image data of the NDT sample at multiple harmonics of the selected frequency in the wideband frequency range based on the detected 3D surface motion, wherein the sub-surface image data describes a nonlinear defect response produced in the NDT sample by interaction of the ultrasonic probe wave with the subsurface region.

Abstract: A device, a method, and a computer program for producing two point light sources of the same wavelength on a pupil plane of an eye of a user are disclosed, as well as a device, a method, and a computer program for determining a neural transfer function of the visual pathway of the user. The device for determining the neural transfer function includes a coherent light source for generating a light beam; an optical device for separating the light beam into sub-light beams, superpositioning the respective sub-light beams, and adjusting contrast and spatial phase in an interference pattern; and a beam path for guiding the superposed sub-light beams such that two point light sources of the same wavelength are produced. The devices are compact and robust, allow a variable presentation of different interference patterns, and can thus be easily operated in a commercial product in a clinical setting.

Abstract: Methods and apparatuses for characterizing life quality of a living entity via hyper-spectral imaging and analysis, and applications thereof, such as managing life quality of a living entity. Includes acquiring hyper-spectral imaging data and information of: anatomical features of the living entity, and substances consumable by the living entity; generating and maintaining a living entity-specific database containing data and information about the living entity; processing acquired living entity anatomical feature and consumable substance hyper-spectral imaging data and information, and living entity data and information; using processed data and information to generate living entity life quality data and information characteristic of life quality of the living entity. Applicable to any living entity (human, animal, plant). Applicable to integrated microelectromechanical (MEM) [chip level] components in desk top devices or miniature smart/intelligent devices.

Abstract: In order to quantitatively characterize biological objects, for example individual cells, a stimulus is applied to a biological object (8) in a contactless fashion. A measurement and a further measurement are performed on the biological object (8) in order to ascertain a response of the biological object (8) to the stimulus, wherein the measurement and the further measurement comprise detecting Raman scattering on and/or in the biological object (8) and/or capturing data using digital holographic microinterferometry (DHMI). The biological object (8) is characterized according to a result of the measurement and is sorted if needed. The stimulus can be applied by means of a laser beam that creates optical tweezers or an optical trap, by means of ultrasonic waves or an electric or magnetic radio frequency field.

Abstract: In a corneal measurement system, an optical element focuses an excitation light to an area of corneal tissue at a selected depth. In response, a fluorescing agent applied to the cornea generates a fluorescence emission. An aperture of a pinhole structure selectively transmits the fluorescence emission from the area of corneal tissue at the selected depth. A detector captures the selected fluorescence emission transmitted by the aperture and communicates information relating to a measurement of the selected fluorescence emission captured by the detector. A controller receives the information from the detector and determines a measurement of the fluorescing agent in the area of corneal tissue at the selected depth. The system may include a scan mechanism that causes the optical element to scan the cornea at a plurality of depths, and the controller may determine a measurement of the fluorescing agent in the cornea as a function of depth.

Abstract: Systems and methods are provided for a UV-VIS spectrophotometer, such as a UV-VIS detector unit included in a high-performance liquid chromatography system. In one example, a system for the UV-VIS detector unit may include a first light source, a signal detector, a flow path positioned intermediate the first light source and the signal detector, a second light source, and a reference detector. The first light source, the signal detector, and the flow path may be aligned along a first axis, and the second light source and the reference detector may be aligned along a second axis, different than the first axis.

Abstract: A QCL may include a substrate, an emitting facet, and semiconductor layers adjacent the substrate and defining an active region. The active region may have a longitudinal axis canted at an oblique angle to the emitting facet of the substrate. The QCL may include an optical grating being adjacent the active region and configured to emit one of a CW laser output or a pulsed laser output through the emitting facet of substrate.

Abstract: A reflectometry instrument includes a light source for emitting an illumination beam that illuminates the macula. A portion of the illumination beam is reflected from the macula and forms a detection beam. The detection beam is indicative of macular pigment in the macula. The instrument also includes a first mirror for reflecting the illumination beam toward the macula and for reflecting the detection beam from the macula. The instrument is configured so that the illumination beam and the detection beam remain separated between the macula and the first mirror.

Abstract: The present invention relates to an apparatus and a method for measuring a thickness and a refractive index of a multilayer thin film using an angle-resolved spectral interference image according to polarization.

Abstract: A sensor system for detection and localisation of changes in or values for at least one environmental condition includes a source of pulses of electromagnetic radiation, wherein the source is configured to emit electromagnetic radiation at a plurality of different wavelengths, an optical fibre in optical communication with the source of pulses, wherein the optical fibre includes a fibre Bragg grating having a reflectance and/or transmittance which varies in dependence on the at least one environmental condition, and a detection unit for detecting electromagnetic radiation which has been reflected or transmitted by the fibre Bragg gratings, wherein the detection unit is configured for detecting electromagnetic radiation at the plurality of wavelengths, such that a spectral response can be determined for different spatial regions along the optical fibre, wherein a change in or value for the environmental condition at a spatial region may be determined by monitoring the respective spectral response.

Abstract: The present disclosure relates to a common-path cube-corner retroreflector interferometer with a large optical path difference and high stability, and an interference technique thereof. The interferometer adopts an asymmetric common-path beam splitting structure using right-angled cube-corner retroreflectors, comprising a semi-transmissive and semi-reflective beam splitter, a plane mirror, a first right-angled cube-corner retroreflector, a second right-angled cube-corner retroreflector and an optical path difference element. The incident light is divided into a first transmitted beam and a second reflected beam, which are respectively reflected by the plane mirror and the right-angled cube-corner retroreflectors several times and then split again, two beams of which become interference outputs along directions perpendicular to an incident direction of the incident light, and the other two beams become interference outputs along directions parallel to the incident light.

Abstract: Systems and methods for precision control of microresonator (MR) based frequency combs can implement optimized MR actuators or MR modulators to control long-term locking of carrier envelope offset frequency, repetition rate, or resonance offset frequency of the MR. MR modulators can also be used for amplitude noise control. MR parameters can be locked to external reference frequencies such as a continuous wave laser or a microwave reference. MR parameters can be selected to reduce cross talk between the MR parameters, facilitating long-term locking. The MR can be locked to an external two wavelength delayed self-heterodyne interferometer for low noise microwave generation. An MR-based frequency comb can be tuned by a substantial fraction or more of the free spectral range (FSR) via a feedback control system. Scanning MR frequency combs can be applied to dead-zone free spectroscopy, multi-wavelength LIDAR, high precision optical clocks, or low phase noise microwave sources.

Abstract: An interferometer arrangement includes a beam splitter (8), two retroreflectors (15, 16), a drive (24) that moves at least one of the retroreflectors to alter an optical path difference between interferometer arms (13, 14), a converging element (18) for reference light, and a reference light detector (19) with at least three detector areas (19a-19d). First and second pairs of detector areas are aligned in respective first and second directions, wherein the first direction, the second direction and a central propagation direction of the reference light at the reference light detector are linearly independent. At least two actuators (9, 10) alter a lateral shear between two reference light partial beams (11, 12), which are reflected back from the interferometer arms and superimposed at the beam splitter, in at least two degrees of freedom. Control electronics (38) control the actuators depending on signals (Sa-Sc) at the detector areas, thereby minimizing the shear.

Abstract: The present invention relates to a method to produce a homogenized tobacco material for use in a heat-not-burn aerosol-generating article, comprising the steps of: selecting a first target value for a first tobacco characteristic, said first tobacco characteristic being reducing sugars and the first target value being comprised between about 8 percent and about 18 percent in dry weight basis of a total amount of tobacco present within the homogenized tobacco material; selecting a second target value of a second tobacco characteristic, wherein the second tobacco characteristic is one of total ammonia and total alkaloids; blending graded tobacco types so as to form the tobacco blend, each graded tobacco type comprising a predetermined amount of the first and second tobacco characteristics, so that the first and second target values of said first and second tobacco characteristics are obtained in said blend within a predetermined tolerance range; grinding said tobacco blend into a blended tobacco powder; form

Abstract: The present invention relates to a method and an assembly for chromatic confocal spectral interferometery, in particular also for spectral domain OCT (SD-OCT) using multi-spectral light. A multiple (e.g. two, three, four, etc.) axial splitting of foci in the interferometric object arm is performed using a multifocal (e.g. bifocal, trifocal, quattro-focal, etc.) optical component, forming thereby at least two, three or even several groups of chromatically split foci in the depth direction. The multifocal optical component is made of a diffractive optical element (712) and a Schwarzschild objective (5). At least two, three, four or even more differently colored foci of different groups of foci coincide in at least one confocal point in the object space of the setup.

Abstract: A method and an interferometric device for spectroscopically or spectrometrically examining a sample, comprising: a) generating a laser beam having a wavelength, b) splitting the laser beam into a measurement beam and a reference beam, c) interacting the sample with the measurement beam, d) interacting a reference with the reference beam, e) overlaying the measurement beam and the reference beam, f) detecting a first output beam, g) detecting a second output beam, h) forming a differential signal between the first output signal and the second output signal, i) controlling the differential signal to a predefined target value, j) determining a refractive index of the sample from the adjustment of the phase difference between the measurement beam and the reference beam, k) repeating steps a) to j) for additional wavelengths of the laser beam.

Abstract: The optical measuring device includes a light source that outputs light of a plurality of wavelengths; a sensor head including a conversion lens that converts light incident via a light guide part, which includes a plurality of cores, into parallel light, and an objective lens that irradiates the light in which chromatic aberration is generated to a measurement object; and a spectroscope that acquires reflected light reflected by the measurement object and condensed by the sensor head via the light guide part and measures a spectrum of the reflected light. In the sensor head, a shield that shields light is arranged between the conversion lens and the objective lens to inhibit light emitted from one core among the plurality of cores included in the light guide part from entering cores other than the one core as the reflected light.

Abstract: An ophthalmic apparatus includes: a light source; a measurement optical system that irradiates an eye with light from the source and guides reflected light from the eye; a reference optical system that guides the light from the source to use the light from the source as reference light; an abnormality detection optical system that has an optical path length of a predetermined length and to guide the light from the source to use the light from the source as abnormality detection light; a light receiving element that receives measurement interference light being combination of the reflected light from the eye and the reference light and abnormality detection interference light being combination of the abnormality detection light and the reference light, and the ophthalmic apparatus determines whether the measurement interference light is abnormal based on waveform of an abnormality detection interference signal outputted from the light receiving element.

Abstract: Apparatus and methods are presented for enhancing the acquisition speed or performance of Fourier domain optical coherence tomography. In preferred embodiments a plurality of wavelength combs containing interleaved selections of wavelengths from a multi-wavelength optical source are generated and projected onto a sample. In certain embodiments the wavelength combs are projected simultaneously onto a plurality of regions of the sample, while in other embodiments the wavelength combs are projected sequentially onto the sample. Light in the wavelength combs reflected or scattered from the sample is detected in a single frame of a sensor array, and the detected light processed to obtain a tomographic profile of the sample. In preferred embodiments the wavelength comb generator comprises a wavelength interleaver in the form of a retro-reflective prism array for imparting different displacements to different selections of wavelengths from the optical source.

Abstract: A gas analysis system with an FTIR spectrometer preferably utilizes a long path gas cell, a narrow band detector, and an optical filter that narrows the detection region. The interferograms are further prevent baseline drift and analyze the resultant spectra.

Abstract: An interferometer system includes a measurement arm comprising a measurement dispersive optical system, a reference arm comprising a bulk diffuser object and a reference dispersive optical system, and an output system. The measurement dispersive optical system is positioned to direct measurement chromatic light towards a target, receive diverging chromatic measurement light from the target, and direct detected measurement light from the received diverging chromatic measurement light towards the output system. The reference dispersive optical system is positioned to direct reference chromatic light towards the bulk diffuser object, receive diverging chromatic reference light from the bulk diffuser object, and direct detected reference light from the received diverging chromatic reference light towards the output system. The output system is configured to determine at least one measured property of the target from the detected measurement light and the detected reference light.

Abstract: Systems and methods are disclosed herein for measuring a fundamental mode vibrational spectrum of materials and substances in the Mid-IR spectral range of 2.5 ?m to 14 ?m wavelength. In one embodiment, a Mid-infrared FT-IR spectrometer system measures, identifies, or quantifies substances in the spectral range 2.5 ?m to 14 ?m. The system includes an infrared Micro-Electro-Mechanical System (MEMS) single element emitter light source. The light source is configured in operation to be electrically pulsed and to emit electromagnetic radiation in the wavelength range from 2.5 ?m to 14 ?m and with integral energy concentrating optic to provide energy for a spectral absorption process. A scanning beam splitter is positioned in an interferometer optical path with fixed angle mirrors and a thermal detector having a sensitivity to determine a maximum optical sensitivity of the system.

Abstract: A Fourier spectroscopic analyzer includes: a light receiver that receives a first wavelength component of a first wavelength band and a second wavelength component of a second wavelength band different from the first wavelength band, emits an interferogram to a sample, and outputs a first light reception signal acquired by receiving the first wavelength component and a second light reception signal acquired by receiving the second wavelength component; and a signal processing device that eliminates noise of the first wavelength component and acquires the spectrum by Fourier transform processing using the first light reception signal and the second light reception signal. The first wavelength band is a wavelength band of which a spectrum is acquired among wavelength components included in light that has passed through the sample. The interferogram is interference light and the sample is an analysis target.

Abstract: The invention relates to a method and a device for the optical measurement of technical surfaces by means of a chromatic confocal sensor, wherein light from a light source (2) is directed to the surface (5) of a sample to be measured via an optical system (4, 14) with defined chromatic aberration. According to the invention, the light source (2) can be tuned in relation to the wavelength to be emitted. The light reflected back from the sample surface (5) is directed to at least one photosensor (7), wherein the sensor signal is measured over time by means of a detection system (8) and the time of a signal maximum is determined. The detection system (8) derives the height Z of the surface (5) from the wavelength of the light source (2) at the time of the signal maximum.

Abstract: A distance measuring arrangement for determining a distance from an object includes at least one light source for producing at least one first monochromatic and interference-capable light beam with a first wavelength and at least one second monochromatic and interference-capable light beam with a second wavelength, a multiplexer for coupling or combining the at least one first light beam and the at least one second light beam into a common measurement beam, an output coupling element for splitting the measurement beam into a reference beam and a signal beam, wherein the reference beam propagates along a reference path and wherein the signal beam propagates along a signal path, and a phase modulator that is arranged in the signal path and configured to modulate the phase of the signal beam periodically in time.

Abstract: In an FTIR 1, a beam splitter 12, fixed mirror 13 and movable mirror 14 are shared by a main interferometer 10 including a multiwavelength infrared light source 11 and a control interferometer 20 including a semiconductor laser 21. A first detector 16 detects infrared interference light generated by the main interferometer 10 and transmitted through or reflected by a sample. A second detector 26 detects monochromatic interference light generated by the control interferometer 20. A spectrum creator 32 determines an optical path difference between an optical path via the fixed mirror 13 and an optical path via the movable mirror 14, based on the intensity and uncalibrated oscillation wavelength of the monochromatic interference light detected by the second detector 26, and creates a spectrum by performing fast Fourier transform on an interferogram which shows a distribution of the intensity of the infrared interference light detected by the first detector 16 with respect to the optical path difference.

Abstract: A device includes a sensor, a coherent infrared illumination source and optics to direct an infrared reference beam to the sensor. The sensor is positioned to capture an image of an interference signal generated by an interference of the infrared reference beam and a wavelength-shifted exit signal. The wavelength-shifted exit signal propagates through the optics before interfering with the infrared reference beam.

Abstract: A measuring device and measuring method for capturing a surface topology of a workpiece uses an optical coherence tomograph having a reference arm guided by a manipulator or a deflection unit to position a measuring region of the scanner. The reference arm is guided along an actual track, which at least partially deviates from an intended track due to disturbing influences like lag errors of the manipulator. An actual distance (dm) between a zero point of the measuring region and a workpiece surface is measured at at least one measuring point of the actual track. A planning path length (Ip) of the reference arm is established for the at least one measuring point for the compensation of the disturbing influences, and the measured actual distance (dm) is normalized to a standard distance (dn) with the aid of the planning path length (Ip).

Abstract: A system for detecting trace-gas includes an optical sensor mounted on a vehicle and processing circuitry. The optical sensor includes a plurality of interferometers configured to collect samples. The processing circuitry is configured to generate a digitized signal based on the samples, apply a forward Fourier-transform on the digitized signal to generate spectrum information for the plurality of interferometers, and determine a gas species has been detected using one or more intensity of absorption features of the spectrum information corresponding to the gas species from the spectrum information.

Abstract: A method of high rate fiber optical distributed acoustic sensing includes injecting a first coherent light pattern comprising first light into an optical cable, the optical cable having at least a first reflector pair and a second reflector pair arranged at different positions along the optical cable; injecting a second coherent light pattern comprising second light into the optical cable while first backscatter light of the first light pattern is propagating in the optical cable; detecting first reflected light originating from reflection of the first light pattern from the first reflector pair and/or the second reflector pair; and, at a different interval in time: detecting second reflected light originating from reflection of the second light pattern from the first reflector pair and/or the second reflector pair.

Abstract: A Fourier-transform interferometer includes a phase change plate including a reflective layer configured to reflect a first light that is incident, and a meta surface configured to locally and differently change a phase of the first light that is reflected. The Fourier-transform interferometer further includes a photodetector configured to detect a second light, and a transflective mirror and a mirror configured to transmit a first part of a third light that is incident, to the phase change plate, transmit a remaining part of the third light, to the photodetector, and transmit the first light of which the phase is locally and differently changed, to the photodetector. The photodetector is further configured to detect an interference pattern between the remaining part of the third light and the first light of which the phase is locally and differently changed.

Abstract: Properties of a sample that are dependent upon wavelength, such as IR absorption, can be detected and deconstructed into wavelets or other basis functions. These basis functions can be compared to determine which have a relatively high likelihood of being noise or signal, and an attenuation factor can be applied to each wavelet. A spectrum can be reconstructed from these wavelets that exhibits a significantly higher signal-to-noise ratio than raw data co-adding would produce in significantly less measurement time.

Abstract: A method and apparatus used for detecting gaseous chemicals. The method and apparatus use an interferometer to filter received light by wavelength, creating an image only using light with wavelengths that are affected by the presence of a gaseous chemical. A reference image composed of light with wavelengths unaffected by the presence of a gaseous chemical is also created and used as a reference. A gaseous chemical is detected where the ratio of the intensity of the two images changes. Despite the high spectral resolution of the filter, the system can operate with a very wide field of view.

Abstract: A tool including a probe deployable within a wellbore and an optical analysis device coupled to the probe is provided. The optical analysis device includes a two-dimensional (2D) waveguide layer to transmit and to disperse an electromagnetic radiation according to wavelength and including detector elements disposed along an edge, each detector element providing a signal associated with a pre-determined wavelength portion of the electromagnetic radiation. The optical analysis device also includes a substrate layer electrically coupled to receive the signal from each of the detector elements and form a spectrum of the electromagnetic radiation with the processor. A method for using the tool in a wellbore application, a pipeline application, or a reservoir storage application is also provided.