33 results about "Optical interferometer" patented technology

A glass including silica and titania is disclosed. An average hydroxyl concentration of a plurality segments of the glass is in a range from about 20 ppm to about 450 ppm, an average titania concentration of the plurality of segments is in a range from about 6 wt. % to about 12 wt. %, and each segment of the plurality of segments has a length of about 12.7 mm, a width of about 12.7 mm, and a height of about 7.62 mm. The hydroxyl concentration of each segment is measured using a Fourier transform infrared spectroscopy in transmission, the refractive index is measured using an optical interferometer with a 633 nm operating wavelength and a resolution of 270 microns×270 microns pixel size, and the average titania concentration is determined based upon the measured refractive index.

The application discloses a vortex light interference device and method for measuring three-dimensional vibration and sound field rotation characteristics, wherein a helium-neon laser emits laser light, the laser light passes through a half-wave plate and a first polarization beam splitter prism, and is divided into object light and reference light; the object light passes through a first spiral phase plate and becomes vortex object light, the vortex object light passes through a second polarization beam splitter prism, a quarter-wave plate, and a beam expander lens, and is irradiated on a test sample surface, reflected light of the sample surface passes through the beam expander lens, the quarter-wave plate, the second polarization beam splitter prism, a beam splitter prism and a focusing lens, and is irradiated on a photodetector; the reference light passes through an acousto-optic modulator to generate frequency modulation, passes through a mirror and a second spiral phase plate to become frequency-modulated vortex light, and the vortex light passes through a beam splitter prism and a focusing lens and is irradiated on the photodetector; a computer calculates and demodulates frequency-modulated signals of the photodetector and modulation signals of the acousto-optic modulator, and finally obtains three-dimensional vibration information and sound field rotation characteristics of the sample.

There is provided a device for phase noise compensation for a frequency modulated continuous wave, FMCW, light detection and ranging, LIDAR, system, said device comprising: an optical interferometer receiving a light signal from a source of the LIDAR system, splitting the light signal into a first and a second light signal into a first and a second path having a preset delay therebetween, and combining the light signals having passed the first and the second path, a detector detecting the combined light signals; a phase noise determination module receiving the detected signal and determining a plurality of phase noise signals corresponding to integer numbers of the preset delay; and a phase noise compensation module receiving and processing a LIDAR response signal in a plurality of branches, and for each branch, compensating phase noise in the LIDAR response signal using one of the phase noise signals, and determining a fast Fourier transform, FFT, of the compensated signal for a specific range of distances to a target, the branches being configured to determine the FFT for mutually unique ranges.

The present invention provides a phase shifter that can be manufactured using a CMOS process, exhibits low optical propagation loss, can maintain refractive index changes without power supply, and allows for the resetting of those refractive index changes. [Solution] The phase shifter 100 of the present invention comprises an optical waveguide 101 composed of a core 105 and a cladding 106 surrounding the core 105, a substrate 102 on which the optical waveguide 101 is mounted, a heating means 103 for heating the core 105, and an ultraviolet irradiation means 104 for irradiating the core 105 with ultraviolet U, wherein the core 105 mainly contains silicon nitride, and the density of silicon dangling bonds of silicon nitride is 10 in terms of spin density 18 cm -3 The above 10 20 cm -3 The following applies:

The optical interferometer comprises: a broadband light source that outputs a first light in a given frequency domain with suppressed relative intensity noise (RIN); a wavelength divider that divides the first light into a first component and a second component with a center wavelength different from the first component and outputs the second component; a first optical path that propagates the first component output from the wavelength divider; a second optical path that propagates the second component output from the wavelength divider; and a wavelength synthesizer that combines the first component propagating in the first optical path and the second component propagating in the second optical path as a second light output.

According to the scheme, the all-fiber mechanical vibration sensor which is based on the magneto-optical effect and senses vibration motion through the optical technology is provided, the modern optical fiber technology and the optical interferometer principle are utilized, optical fibers are adopted as sensing materials and optical transmission materials, and sensing of mechanical vibration to be detected is achieved through light beams in the optical fibers. Sensing parts do not contain devices which are susceptible to external electromagnetic interference and damage the insulation degree, such as conductive wires, and optical sensing vibration information can be accurately and safely completed in a passive, non-contact and loss-free manner at a high speed. The optical fiber sensing device has the advantages of simple optical fiber sensing structure, small size, high reliability, high response speed, wide signal frequency band, high safety and the like. The all-fiber mechanical vibration sensor can be used for sensing and monitoring vibration states and vibration characteristics of various rotating machines, and can also be used for optically sensing and monitoring vibration states of non-rotating machines, so that the mechanical equipment can realize intelligent and safe operation.

Described herein are compact, high-power tunable optical sources with precise wavelength control. The tunable optical sources developed by the inventors and described herein use laser arrays that are compatible with wavelength division multiplexing (WDM) schemes, making these sources particularly suitable for use in applications requiring high levels of data throughput. These sources use integrated wavemeters to measure the wavelength of optical emission. These wavemeters are formed monolithically on the same substrate hosting the laser array, resulting in a much smaller footprint than what is possible using conventional, external instrumentation. The wavemeters described herein use optical interferometers as part of a feedback control loop to ensure that the lasers emit light at the desired carrier wavelengths. A wavemeter can map the wavelength of emission of a laser to the wavelengths of emission of a calibrated optical source.

A method includes causing activation, at a first time, of a first set of squeezed light sources from a plurality of squeezed light sources of a Gaussian boson sampling (GBS) circuit. At a second time after the first time, a first photon statistic is detected at a first output port from a plurality of output ports of the GBS circuit. At a third time after the first time, a second set of squeezed light sources from the plurality of squeezed light sources of the GBS circuit is activated, the second set of squeezed light sources being different from the first set of squeezed light sources. At a fourth time after the third time, a second photon statistic is detected at a second output port from the plurality of output ports of the GBS circuit. At least one transformation matrix is estimated that represents a linear optical interferometer of the GBS circuit based on the first photon statistic and the second photon statistic.

The present invention comprises one or a plurality of optical interferometers including a plurality of arm waveguides (216) that guide respective light split at optical splitting units (330a, 331a, and 332a) to optical multiplexing units (332b, 331b, and 219), the light undergoing different phase changes between different arm waveguides. The optical splitting units and the optical multiplexing units are arranged in a direction different from the direction in which the end face of the optical splitting unit (330a, 331a or 332a) from which the light is outputted and the end face of the optical multiplexing unit (332b, 331b or 219) to which the light is inputted face each other. Each of the arm waveguides (216) has a shape along a path that includes a curved portion in accordance with the different direction mentioned above between the output end face of the optical splitting unit and the input end face of the optical multiplexing unit. The optical path length difference between different arm waveguides on the path including the curved portion is less than or equal to the wavelength of the light.

The invention discloses a multimode optical fiber spot homogenizing device for a spherical optical interferometer, which comprises an ultrasonic oscillation cavity, the ultrasonic oscillation cavity is filled with coupling liquid, the temperature of the coupling liquid is adjusted through a temperature control device, a stress adjusting device is fixedly arranged in the ultrasonic oscillation cavity and is soaked in the coupling liquid, and the stress adjusting device is used for adjusting the temperature of the coupling liquid. The stress adjusting device adjusts mechanical stress borne by the multimode optical fiber, and the ultrasonic oscillation cavity is connected with the ultrasonic oscillator. The invention further discloses a multi-mode optical fiber light spot homogenizing method for the spherical optical interferometer, the refractive index of the multi-mode optical fiber is changed through microwave heating, and the output light spots of the multi-mode optical fiber are homogenized by combining the synergistic effect of mechanical stress and ultrasonic vibration. The device is simple in structure and convenient to operate, thermal damage to the multimode optical fiber is reduced, and long-term stable operation of equipment is facilitated.

Described herein are compact, high-power tunable optical sources with precise wavelength control. The tunable optical sources developed by the inventors and described herein use laser arrays that are compatible with wavelength division multiplexing (WDM) schemes, making these sources particularly suitable for use in applications requiring high levels of data throughput. These sources use integrated wavemeters to measure the wavelength of optical emission. These wavemeters are formed monolithically on the same substrate hosting the laser array, resulting in a much smaller footprint than what is possible using conventional, external instrumentation. The wavemeters described herein use optical interferometers as part of a feedback control loop to ensure that the lasers emit light at the desired carrier wavelengths. A wavemeter can map the wavelength of emission of a laser to the wavelengths of emission of a calibrated optical source.

The present invention addresses the need to implement a side rearview mirror monitoring system that detects malfunctions caused by temperature changes, vibrations, and impacts. A side rearview mirror monitoring system is provided, comprising fiber optic sensors integrated into the rearview mirror assembly and connected to the Door Control Module (DCU).The DCU unit comprises at least the following elements: a) an optical interferometer that measures the light wave reflected by the fiber optic sensors located inside each side rearview mirror; b) a digital signal processor (DSP), whose main characteristic is the processing of digital signals at the physical level; and c) a reference fiber optic section, which is a segment or section of the fiber optic sensor embedded and sealed with epoxy paste inside the DCU module to prevent movement. Once the temperature, pressure, and vibration data is collected and processed, the system can use this information to correct errors in the position of the side rearview mirrors or detect impacts to them. If these events occur, a signal can be sent to the DCU module's actuator to fold the exterior mirror to prevent damage and / or adjust its position.In addition, the system can also send notifications regarding the operation of the rearview mirrors to the BCM module via a vehicle's CAN bus.

The invention relates to an optical processor (2), in particular to an optical interferometer, comprising: a plurality of processor input ports (5.1 to 5.4) for receiving input optical signals (4.1 to 4.4), a plurality of processor output ports (6.1 to 6.4) for emitting output optical signals (7.1 to 7.4), and an optical network (9) that connects the processor input ports (5.1 to 5.4) to the processor output ports (6.1 to 6.4) and comprises at least one layer (11) with a plurality of optical devices (10a-c) configured to process the input optical signals (4.1 to 4.4) from the processor input ports (5.1 to 5.4). The at least one layer (11) has a plurality of input ports (14.1 to 14.4) and a plurality of output ports (15.1 to 15.4) that are connected to the plurality of input ports (14.1 to 14.4) via optical delay lines (16.1 to 16.4). The invention also relates to an apparatus (1), comprising: an optical processor (2) as indicated above, a plurality of light sources (3.1 to 3.4) for generating the plurality of input optical signals (4.1 to 4.4) for the optical processor (2), and a plurality of optical detectors (8.1 to 8.4) for detecting the output optical signals (7.1 to 7.4) from the optical processor (2).

This disclosure provides transabdominal fetal oximetry (TFO) that uses frequency-modulated continuous-wave (FMCW) time-domain near-infrared spectroscopy to measure time-resolved reflectance values of light signals collected from a maternal-fetal multilayer tissue structure. In various embodiments, the disclosed FMCW time-domain near-infrared spectroscopy is configured to function as an optical interferometer that uses two frequency-swept laser sources of different center wavelengths λ1 and λ2 as probe lights to detect optical property in vascular tissues of the maternal-fetal multilayer tissue structure. The FMCW near-infrared spectroscopy is configured to collect light signals returned from the multilayer structure and generate a time-resolved reflectance curve based on the collected light signals.

This invention provides an adaptive fusion method for attitude jitter error noise in optical interferometers. The specific process is as follows: First, acquire multiple attitude jitter error noise data collected by differential wavefront sensitive angle measurement based on a four-quadrant detector, along with real-time operating status parameters of the DWS; unify the frame rate through adaptive downsampling; filter valid data through a two-layer validity judgment; achieve time synchronization using step calibration and dynamic compensation; construct a dual-objective adaptive weight calculation model based on an improved Adam optimizer, introduce a robust penalty term to suppress abnormal data interference, and calculate dynamic weight parameters in real time; fuse the weight parameter data to ensure stable fusion results and output optimal attitude jitter error noise data. This invention solves the problems of weak anti-interference capability, low fusion accuracy, and insufficient real-time performance of existing fusion methods. Through multi-stage collaborative optimization, it improves the accuracy and stability of attitude jitter error noise fusion, making it suitable for the complex and precise working scenarios of optical interferometers.

A phase shifter (100) according to the present invention is provided with: an optical waveguide (101) formed of a core (105) and a cladding (106) surrounding the core (105); a substrate (102) on which the optical waveguide (101) is mounted; a heating means (103) for heating the core (105); and an ultraviolet irradiation means (104) for irradiating the core (105) with ultraviolet rays U. The core (105) contains silicon nitride as the main component, and the density of silicon dangling bonds of the silicon nitride is 1018-1020 cm-3 as expressed in spin density.<sp / >

A glass including silica and titania is disclosed. An average hydroxyl concentration of a plurality segments of the glass is in a range from about 20 ppm to about 450 ppm, an average titania concentration of the plurality of segments is in a range from about 6 wt. % to about 12 wt. %, and each segment of the plurality of segments has a length of about 12.7 mm, a width of about 12.7 mm, and a height of about 7.62 mm. The hydroxyl concentration of each segment is measured using a Fourier transform infrared spectroscopy in transmission, the refractive index is measured using an optical interferometer with a 633 nm operating wavelength and a resolution of 270 microns×270 microns pixel size, and the average titania concentration is determined based upon the measured refractive index.

A light detection and ranging (LiDAR) device includes a transmission unit configured to project a transmission signal toward an object, an optical element between the transmission unit and the object and configured to partially reflect the transmission signal projected by the transmission unit, a reception unit including at least one optical interferometer configured to generate a first optical signal by mixing a first reception signal reflected from the object with the transmission signal and a second optical signal by mixing a second reception signal reflected from the optical element with the transmission signal, and at least one photodetector (PD) configured to convert the first optical signal and the second optical signal into a first beat signal and a second beat signal, respectively, and a processor configured to generate a clock signal based on the second beat signal and correct the first beat signal based on the clock signal.

An optical interrogation system for high definition-distributed acoustic sensing (HDDAS) of a vibration that changes a length of an optical fiber sensor in contact with a material or structure includes an optical interferometer, optical detection circuitry, coupled to the optical interferometer, for detecting optical interferometric measurement signals for a length of the optical fiber sensor, and data processing circuitry. The data processing circuitry receives interferometric measurement signals from the optical detection circuitry and generate, based on the interferometric measurement signals, interferometric measurement data for a length of the optical fiber sensor. It processes the interferometric measurement data to determine a strain state of the optical fiber sensor at one or more locations along the optical fiber sensor and determines a vibration component of the strain state of the optical fiber sensor at the one or more locations along the optical fiber sensor.

The invention relates to an interferometer sensing measurement method based on a special reference spectrum vernier effect, which comprises the following steps: S101, according to a spectrum measurement range and an interferometer cavity length change range caused by a measured physical quantity, establishing a relational expression that a free spectral range (FSR) of a virtual reference interferometer spectrum changes along with wavelength; s102, obtaining a spectral curve of the reference interferometer; s103, superposing the actually measured spectrum curve of the sensing interferometer and the spectrum curve of the reference interferometer, and obtaining a total spectrum curve of which the envelope appears the characteristic wavelength based on a vernier effect; and S104, monitoring the change of the characteristic wavelength along with the measured physical quantity, and completing the measurement according to the calibrated relationship between the characteristic wavelength and the measured physical quantity. According to the invention, only one optical interferometer is needed, a special reference spectrum is constructed according to the measured physical quantity and the measurement range of the spectrum, and the unique recognizable characteristic wavelength can be obtained based on the vernier effect, so that the ambiguity resolution and high-sensitivity measurement of the physical quantity are realized.

A wafer thickness measurement device of the present invention obtains, based on: first and second interferometer reference measurement results obtained by measuring, with an A-surface optical interferometer and a B-surface optical interferometer, a reference measurement point on a reference piece having the reference measurement point at which the reference piece has a known thickness; first and second distance meter reference measurement results obtained by measuring the reference measurement point with an A-surface distance meter and a B-surface distance meter; first and second interferometer measurement results obtained by measuring a measurement point of the wafer with the A-surface optical interferometer and the B-surface optical interferometer; and first and second distance meter measurement results obtained by measuring the measurement point with the A-surface distance meter and the B-surface distance meter, and obtains a thickness, of the wafer, at the measurement point.

The optical interference distance measuring device (100) includes a first lens (15) that focuses signal light (51A) emitted from an optical transmission component (18) onto an object (19) to be measured, a second lens (16A) for scanning at a first magnification, a third lens (16B) for scanning at a second magnification higher than the first magnification, and a lens switching unit (16) that inserts the second lens (16A) between the first lens (15) and the optical transmission component (18) when scanning at the first magnification, and inserts the third lens (16B) between the first lens (15) and the optical transmission component (18) when scanning at the second magnification, characterized in that the distance between the first lens (15) and the object (19) is maintained in a state in which the signal light (51A) can be focused onto the surface of the object (19).

The application discloses a multimode coherent Mach-Zehnder optical interferometer and a control method thereof. The multimode coherent Mach-Zehnder optical interferometer comprises a first beam splitter, a plurality of multimode phase shift regions and a second beam splitter. The first beam splitter comprises M input ends and N output ends. The input ends of the first beam splitter are used for receiving multimode light. The output ends of the first beam splitter are used for outputting beam-splitting multimode light. The input ends of the plurality of multimode phase shift regions are connected with the output ends of the first beam splitter. The input ends of the plurality of multimode phase shift regions are used for receiving the beam-splitting multimode light. The multimode phase shift regions compensate the light phases of all modes of the beam-splitting multimode light. The output ends of the plurality of multimode phase shift regions are used for outputting processed multimode light. The second beam splitter comprises N input ends and L output ends. The input ends of the second beam splitter are connected with the output ends of the plurality of multimode phase shift regions. The input ends of the second beam splitter are used for receiving the processed multimode light. The output ends of the second beam splitter are used for outputting combined multimode light. The application can realize the function of multimode light coherence.

A distributed acoustic sensing system can include an optical interferometer. The optical interferometer can include a fiber coupler for splitting an optical light signal, and a fiber delay coil for introducing a controlled time delay in one of the paths. At least one path can form a loop, enabling controlled delay and temporary storage of light, resulting in an interference pattern. The system can gradually mitigate noise or distortion, improving sensitivity of defect detection and / or signal reception quality.

Described herein are devices, systems, and methods for implementing free-space multi-channel optical interferometers. Such interferometers may include a beam-splitting device or assembly that performs the various beam-splitting and beam-combining functions, and multiple collimator devices configured in pairs that map light for the multiple optical channels along the interferometer paths between sets of waveguide cores. The interferometer may include one or more of the following features: high-precision collimator assemblies constructed from a waveguide array and two collimator lenses whose distance is carefully set to achieve a desired focal length, a transparent plate or set of plates with selective beam-splitting surface coatings serving as the beam-splitting device, and a planar light circuit (PLC) free-space-coupled to an optical fiber to split light from the optical fiber between multiple waveguide cores for the multiple optical channels, optionally with a polarization controller or modulator inserted between optical fiber and PLC for polarization-diverse interferometry.

There is described a method of detecting an anomaly in a transaction network using an optical quantum-computing device. The method comprises obtaining transaction information. generating a transaction graph based on the transaction information. encoding inputs of a Gaussian Boson Sampling (GBS) device based on the transaction graph. processing outputs of the GBS device to identify one or more dense subgraphs of the transaction graph. and generating a detection output identifying one or more of the identified dense subgraphs as representative of a potential anomaly. There is also described an apparatus for detecting an anomaly. comprising a GBS device having a photon source. a linear optical interferometer and a photon detector. and a computer device configured to program inputs of the GBS device.

Neuromorphic computing can employ coherent linear optical neurons implemented with multipath optical interferometers in which optical amplitude modulators and phase shifters impart neuron input signals and neuron weights onto optical carrier signals that are then summed at the interferometer output. Photodetectors at the interferometer output, optionally in conjunction with preceding nonlinear optical circuits, may implement a non-linear activation function and generate electronic neuron output signals that can be provided as input to other optical neurons to form an optical neural network.

The present application provides an OCT measuring device and an OCT measuring method. The OCT measuring device (1) comprises: a wavelength scanning light source (2) that emits light whose wavelength is scanned; an optical interferometer (9) that splits light into measurement light (18) and reference light (19), generates an optical interference intensity signal that indicates the intensity of the interference between the measurement light (18) that is irradiated to a measurement surface (21) of an object (20) to be measured and the reference light (19) that is reflected by the measurement surface (21); a phase modulation section (17) that is disposed in the optical path of the optical interferometer (9); a signal generation section (3) that derives the position of the measurement surface (21) based on the optical interference intensity signal, and generates a phase amount indication signal that indicates the phase amount of the phase modulation section (17); and a phase amount control section (6) that controls the phase amount imparted to the light that is transmitted through the phase modulation section (17) based on the phase amount indication signal.

The invention relates to a single-photon time slice digital overlay method of a distributed spatial light interference telescope, and belongs to the field of spatial astronomical telescopes. The method comprises the following steps: 1) constructing a distributed spatial light interference light path, and carrying out co-phase adjustment; 2) interference imaging: observing a target source and recording measurement data; 3) screening the interference imaging data according to the optical path difference data screening range; and 4) carrying out data superposition on the screened measurement data to form an anti-disturbance high-contrast interferogram. Single-photon imaging slice data are screened through co-phase detection, it is guaranteed that slice data of a synthetic interference pattern are co-phase when co-phase control is insufficient, and effective observation of extrasolar planets is achieved.

The invention discloses an optical leak detection device and an optical leak detection method, and the device comprises a pressure cavity which is internally provided with a pressure chamber for placing a sample, the pressure cavity is provided with a window, and the window is internally provided with a transparent medium; the optical interferometer is arranged outside the pressure cavity and comprises an interferometer main body and an interference objective lens arranged on the interferometer main body, the interference objective lens comprises a spectroscope, a reference lens, a compensating plate and a plurality of microobjective lenses, the reference lens is arranged on a reflection light path of the spectroscope, and the compensating plate is arranged on a reflection light path of the spectroscope; the microscope objective is arranged on an incident light path, a transmission light path or a reflection light path of the spectroscope, the compensating plate is arranged on the reflection light path of the spectroscope and located between the spectroscope and the reference mirror, the material of the compensating plate is the same as that of the transparent medium, and the thickness of the compensating plate is the same as that of the transparent medium; wherein the transparent medium is located on a transmission light path of the spectroscope, and the distance from the sample surface to the spectroscope is equal to the distance from the reference mirror to the spectroscope. The optical leak detection device is convenient to operate and lower in cost.