26 results about "Interferometric sensor" patented technology

A method and system for determining and controlling a separation distance between a machine tool work head and a material surface is described, comprising: - generating a measuring beam of low-coherence optical radiation, directing the measuring beam towards the material and directing the measuring beam reflected or diffused from the material surface towards an optical interferometric sensor arrangement in a first direction of incidence, - generating a reference beam of low-coherence optical radiation and directing the reference beam towards the optical interferometric sensor arrangement in a second direction of incidence at a pre-set angle of incidence with respect to the first direction of incidence of the measuring beam; - superimposing the measuring beam and the reference beam on a common area of incidence of the sensor arrangement; - detecting a position of an interference fringe pattern between the measuring beam and the reference beam on the area of incidence; and - determining, based on the position of the interference fringe pattern along an axis of illumination of the area of incidence, an optical path difference between the measuring optical path and the reference optical path, which optical path difference represents a difference between (a) a current separation distance between the work head and the material surface and (b) a predetermined nominal separation distance.

Described herein are interferometric sensors that can be used for biochemical testing. Each interferometric sensor includes an interference layer immobilized along a surface of a monolithic substrate. Analyte binding molecules can be coated along a surface of the interference layer. During biochemical testing, when analyte molecules in a sample bind to the analyte binding molecules, a biological layer will form. The monolithic substrate has a higher refractive index than the interference layer. Furthermore, the interference layer can be designed to have a refractive index that is substantially similar to a refractive index of the biological layer.

Ultracold atom measurement system and associated method The present invention relates to an ultracold atom measurement system (10), the measurement system (20) comprising: - an array of ultracold atom inertial sensors (14), each sensor (14) of the array being an interferometric sensor configured to measure a physical quantity by implementing an interferometry sequence, - a processing unit (22) configured to apply, for at least one subset of sensors, a respective interferometry sequence to each sensor (14) of a subset of sensors, the implementation of the respective interferometry sequences by said at least one subset of sensors (14) leading the sensors (14) of the subset to measure the same physical quantity with a trajectory followed during the movement varying from one sensor (14) of the subset to another sensor (14) of the subset by at least one parameter relating to the trajectory.Figure for the abbreviation: figure 1.

The invention is based on a method of using a laser feedback interference (LFI) sensor (10), in particular a virtual retinal display (12), preferably in data glasses (14), in which at least one laser beam (16) is output by the LFI sensor (10), and in which a reflected signal (18) originating from a previously output laser beam (16) is recorded by the LFI sensor (10). According to the invention, the pulse rate of the owner of the eye (24) and / or the blood flow direction of at least one blood vessel of the eye (24) is determined from a detected reflected signal (18) of the LFI sensor (10), said reflected signal comprising a laser speckle reflection pattern (20) of the retina (22) of the eye (24).

Introduced here is an approach to programmatically addressing the absorbance of light by analyte molecules whose binding, for example, to an interferometric sensor, is being monitored by an interferometric sensing system. A first light signal may be shone upon a biolayer over the course of a biochemical test, and the light reflected by the biolayer may form a second light signal that is detectable by a detector of an interferometric sensing system. Through analysis of the second light signal, the second light signal can be deconvolved into a reflection component and an absorbance component. If the principal component of the second light signal is the reflection component, then one algorithm may be employed to establish the binding magnitude. If the principal component of the second light signal is the absorbance component, then another algorithm may be employed to establish the binding magnitude.

The utility model relates to the field of optical fiber interference sensors, and discloses an M-Z interference sensor of a seven-core optical fiber cascaded graded-index multimode optical fiber, which comprises a light injection single-mode optical fiber, a step multimode optical fiber, a seven-core optical fiber, a graded-index multimode optical fiber and a light receiving single-mode optical fiber which are connected in sequence, the axis of the joint of the seven-core optical fiber and the gradient refractive index multimode optical fiber deviates by a preset offset; the outer side of a fiber core of the seven-core optical fiber is coated with a stress layer, and the radius of the fiber core of the step multimode optical fiber is larger than the radius of the stress layer of a central fiber core of the seven-core optical fiber and smaller than the minimum distance from the central fiber core of the seven-core optical fiber to the stress layer of the fiber core on the outer side of the seven-core optical fiber. The length of the seven-core optical fiber is far smaller than that of the gradient multimode optical fiber; and the refractive index of the stress layer material outside the fiber core of the seven-core optical fiber is smaller than that of the cladding material of the seven-core optical fiber. According to the scheme, the problems that the interference valley is too wide and the extinction ratio is too low in a gradient refractive index multimode optical fiber interference sensor can be solved while the high-sensitivity sensing characteristic is maintained.

The present invention discloses a polarization-maintaining fiber end-face Michelson interferometric sensor with low cost and reproducible production. Both the transmission fiber and the sensing fiber adopt polarization-maintaining fibers to maintain the polarization state of the fiber. The free end of the sensing fiber consists of a part of an inclined end-face and a part of a perpendicular end-face. The inclined end-face forms a 45° angle with the axis of the sensing fiber, vertically emitting the light in the core or coupling the light perpendicular to the core into the core. The light reflected by the perpendicular end-face part of the core will be transmitted in the reverse direction. The light reflected by the inclined end-face part of the core enters the core again after being reflected by the outer wall of the cladding, and interferes with the light reflected by the perpendicular end-face, constituting an end-face Michelson interferometer. This sensor structure can be used for the measurement of temperature or transverse stress, has reproducibility, eliminates the influence of environmental disturbances on the polarization state of the transmitted light, and improves the stability of the structure; it has low cost, simple preparation, and compact structure.

A head mounted device may include one or more interferometric sensors positioned and oriented in a housing to sense particle movement caused by respiration of a user. Interferometric signals from the one or more interferometric sensors may be used to determine respiration information about the user.

The present invention relates to an objective (3) for a confocal system (1) of spectral interferometric measurement, comprising: —a source hole (14); —a second beam splitter (12) having a partially reflective face (12a), —a first beam splitter (10) having a face which is configured to form a reference surface (6) and being located between the source hole (14) and the second beam splitter (12); and—lenses (11, 13). The first and second beam splitters are positioned in the objective (3) such that an optical distance (dref) between the reference surface (6) and the partially reflective surface (12a) is substantially equal to an optical distance (dm) between the partially reflective surface (12a) and a focal plane of the objective (3).

An optical fiber-based monitoring system and associated method includes a light source structured and configured for generating a first light signal, one or more multimode interferometric fiber structures, such as an SMS or SMSMS fiber structure, structured and configured to receive the first light signal and output an output light signal indicative of a parameter associated with the multimode interferometric fiber structure, and a photodetector coupled to an output of multimode interferometric fiber structure for converting the output light signal into an electrical signal.

The present invention discloses a method for preparing a stepped waveguide microcavity refractive index sensor, comprising the following steps: (1) using femtosecond laser writing technology to write a straight single-mode waveguide in a transparent substrate material; and (2) using micromachining technology to prepare a stepped microcavity on one side of the waveguide region. The stepped microcavity structure consists of two rectangular microcavities of different lengths and widths, the length directions of the two microcavities being along the waveguide transmission direction, and the two rectangular cross-sections perpendicular to the waveguide transmission direction each covering a portion of the waveguide mode field, while the sum of the two rectangular cross-sections does not cover the entire waveguide mode field. Compared with existing waveguide microcavity interferometric sensors, this method can overcome the FSR limitation on the refractive index detection range, thereby accurately reading the actual refractive index value of the liquid within a larger refractive index variation range.

Introduced here is an approach to programmatically addressing the absorbance of light by analyte molecules whose binding, for example, to an interferometric sensor, is being monitored by an interferometric sensing system. A first light signal may be shone upon a biolayer over the course of a biochemical test, and the light reflected by the biolayer may form a second light signal that is detectable by a detector of an interferometric sensing system. Through analysis of the second light signal, the second light signal can be deconvolved into a reflection component and an absorbance component. If the principal component of the second light signal is the reflection component, then one algorithm may be employed to establish the binding magnitude. If the principal component of the second light signal is the absorbance component, then another algorithm may be employed to establish the binding magnitude.

The invention relates to a vertical cavity surface emitting laser (VCSEL) device (100) of a self-mixing interferometric sensor (300) for recording three-dimensional images, the VCSEL device (100) comprising a VCSEL array, a plurality of detectors (140), a first electric laser contact (105) and at least one second electric laser contact (127), wherein the VCSEL array comprises a plurality of laser diodes (122), wherein each laser diode (122) comprises an optical resonator, wherein the optical resonator comprises a first distributed Bragg reflector (115), a second distributed Bragg reflector (135) and an active layer (120) for emitting light, wherein the active layer (120) is arranged between the first distributed Bragg reflector (115) and the second distributed Bragg reflector (135). A distributed Bragg reflector (135) is provided, wherein a first electric laser contact (105) and the at least one second electric laser contact (127) are arranged to provide an electric drive current to electrically pump an optical resonator of a laser diode (122), wherein the first electric laser contact (105) is a common contact for all laser diodes (122) of a VCSEL array, wherein the at least one second electric laser contact (127) is arranged to be able to make electrical contact with at least a subset of the plurality of laser diodes (122) of the VCSEL array, wherein each detector (140) is arranged to generate an electric self-mixing interferometry signal associated with at least one laser diode (122) upon receiving laser light (10). The present invention also relates to a self-mixing interferometry sensor (300) for recording three-dimensional (3D) images, a VCSEL device, and a method for manufacturing such a VCSEL device.

A self-mixing interferometric sensor device comprises a laser diode, a photodiode, a first readout unit for generating a first readout signal from a measurement signal of the photodiode, a second readout unit for generating a second readout signal from a junction voltage of the laser diode, and a switching unit configured to generate an output signal from the first readout signal in a first operating mode and to generate the output signal from a second readout signal in a second operating mode. The sensor device is configured to switch between operation in the first operating mode and operation in the second operating mode.

A head mounted device may include one or more interferometric sensors positioned and oriented in a housing to sense particle movement caused by respiration of a user. Interferometric signals from the one or more interferometric sensors may be used to determine respiration information about the user.

Introduced here is an approach to programmatically addressing the absorbance of light by analyte molecules whose binding, for example, to an interferometric sensor, is being monitored by an interferometric sensing system. A first light signal may be shone upon a biolayer over the course of a biochemical test, and the light reflected by the biolayer may form a second light signal that is detectable by a detector of an interferometric sensing system. Through analysis of the second light signal, the second light signal can be deconvolved into a reflection component and an absorbance component. If the principal component of the second light signal is the reflection component, then one algorithm may be employed to establish the binding magnitude. If the principal component of the second light signal is the absorbance component, then another algorithm may be employed to establish the binding magnitude.

This invention discloses a cascaded hollow-core fiber interferometric sensor and its fabrication process, relating to the field of hollow-core fiber measurement technology. The cascaded hollow-core fiber interferometric sensor comprises, in sequence, a broadband light source (1), a first fiber optic jumper (2), a first single-mode fiber (3), a first fusion splice (4), a first anti-resonant Bragg hollow-core fiber (5), a second fusion splice (6), a second single-mode fiber (7), a third fusion splice (8), a second anti-resonant Bragg hollow-core fiber (9), a fourth fusion splice (10), a third single-mode fiber (11), a second fiber optic jumper (12), and a spectrometer (13). Compared with existing technologies, ① the integrated fiber Fabry-Perot interferometric structure and high-precision anti-resonance fiber temperature sensing structure provided by this invention enable large dynamic range measurement and temperature calibration. ② The anti-resonant hollow-core fiber provided by this invention enables miniaturized fiber optic temperature sensors.

The invention discloses a microwave photon optical fiber interference sensor sensitivity enhancing system. The system comprises a broadband light source, an optical fiber coupler, an optical fiber interference sensor, a narrowband filtering element, an optical fiber amplifier, an electro-optical modulator, a dispersion module, a photoelectric detector and a vector network analyzer which are arranged on the same light path. In order to improve the performance of the optical fiber interference sensor enabled by the microwave photonic filter in precision measurement, coherent microwave superposition is carried out on passband frequency response of the optical fiber interference sensor and flat frequency response of a narrow-band filtering element through an optical fiber coupler, so that trapped waves which are more sensitive to interference spectrum information are generated in a passband; the frequency and the intensity are related to the optical path difference of the optical fiber interference sensor. Through a trap demodulation mechanism based on coherent microwave superposition, the sensing sensitivity of the microwave photon optical fiber interference sensor can be remarkably improved.

A multi-channel SMI sensor includes an emitter configured to emit light having different polarizations and a polarization-selective lens for directing light having different polarizations towards different locations. The multi-channel SMI sensor is configured to measure physical phenomena at two different locations with a small footprint.

A post-quantum encryption system utilizes cymatics patterns formed in a liquid medium (102) for high-entropy cryptographic key generation. The system includes a container (101) holding the liquid medium, and one or more vibration sources (105) configured to generate acoustic waves that induce dynamic ripple formations. A temperature control unit (106) adjusts the medium's thermal state to modulate waveform complexity. Sensors (107), including high-speed imaging units (108) and interferometric sensors (109), capture wave patterns in real-time. A signal processing module extracts parameters such as amplitude, wavelength, and frequency, which are converted into a cryptographic key via a secure interface. The key may be used in symmetric, asymmetric, or post-quantum algorithms. Optionally, a quantum key distribution (QKD) module (127) transmits the generated key securely. The invention leverages physical randomness and acoustic-fluid dynamics to provide scalable, tamper-resistant encryption suitable for next-generation security infrastructure.

An ultracold atom measuring system, the measuring system including an assembly of ultracold atom inertial sensors, each sensor of the assembly being an interferometric sensor configured to measure a physical magnitude by implementing an interferometry sequence, a processing unit configured, for at least one sub-assembly of sensors, to apply a respective interferometry sequence to each sensor of a sub-assembly of sensors, the implementation of the respective interferometry sequences by the at least one sub-assembly of sensors causing the sensors of the sub-assembly to measure the same physical magnitude following a travel trajectory when displaced varying, from one sensor of the sub-assembly to another sensor of the sub-assembly, by at least one trajectory-related parameter.

A sensing device (20, 60) configured to fit on a head of a user (24) includes an optical sensing head (28, 68) held by the device in a position proximate the user's face, and includes an emitter (70) configured to direct coherent light toward a plurality of locations on the body surface of the user and an interference sensor (76) configured to sense a phase change of the coherent light reflected from the plurality of locations on the body surface. The processing circuit (36) is configured to apply the sensed phase change in generating the speech output. Other sensing modalities are also disclosed.

The invention discloses a demodulation method and system for improving the sensitivity of an interference type sensor, and relates to the technical field of sensor sensitivity demodulation, and the method comprises the steps: obtaining the original spectrum data of the interference type sensor; according to the original spectral data, calculating a free spectral range of the interference type sensor, and calculating a sampling interval value in combination with a preset target amplification factor; carrying out two times of interval sampling on each piece of spectral data in the original spectral data to generate a first envelope and a second envelope of the spectral data; taking an intersection point of the first envelope and the second envelope of each piece of spectral data as a feature tracking point, and determining a wavelength value of the feature tracking point; according to the wavelength values of all the feature tracking points, calculating wavelength drift distances of all the feature tracking points; and demodulating the to-be-measured parameters according to the wavelength drift distances of all the feature tracking points. According to the invention, the demodulation cost can be reduced, the demodulation efficiency can be improved, the matching of the high-order harmonic vernier effect can be realized, and the ultra-high-sensitivity amplification measurement can be realized.

A self-mixing interferometric sensor device comprises a laser diode, a photodiode, a first readout unit for generating a first readout signal from a measurement signal of the photodiode, a second readout unit for generating a second readout signal from a junction voltage of the laser diode, and a switching unit adapted to generate an output signal in accordance with the first readout signal in the first operating mode and to generate an output signal in accordance with the second readout signal in the second operating mode. The sensor device is adapted to switch between operating in a first operating mode and operating in a second operating mode.

A method for operating a self-mixing interferometric sensor is provided. The sensor comprises: - a VCSEL-array (2) with a plurality of VCSEL-elements (3), each VCSEL-element (3) being configured for self-mixing interferometry, - a photodiode-array (6) with a plurality of photodiode elements (7), each photodiode element (7) being configured for detecting electromagnetic radiation (20) leaking from a backside surface (5) of a VCSEL-element (2), wherein the photodiode elements (7) produce SMI-signals (8). The method comprises the steps: - determining a vital sign (16) from the SMI-signals (8) in a first operation mode, and / or - determining the vital sign (16) from the SMI-signals (8) in a second operation mode. Further, a self-mixing interferometric sensor is provided.

The apparatus for measuring a thickness of a workpiece of this disclosure comprises an enclosure; a measurement section disposed inside the enclosure for measuring the thickness of the workpiece; and a rectifier disposed inside the enclosure for rectifying airflow inside the enclosure, wherein the measurement section is provided with a spectral interferometric sensor. In the system for polishing a workpiece of this disclosure, the apparatus for measuring a thickness of a workpiece above is installed in each of the workpiece carry-in unit and the workpiece carry-out unit. In the method for measuring a thickness of a workpiece of this disclosure, the thickness of the workpiece is measured using a measurement section comprising a spectral interferometric sensor, the measurement section is disposed inside an enclosure, and the thickness of the workpiece is measured by the measurement section while rectifying airflow in the enclosure using a rectifier disposed inside the enclosure.