140 results about "Optical delay line" patented technology

According to the optical carrier microwave stable transmission system based on the temperature control optical fiber delay line provided by the invention, accurate reverse compensation is carried out on delay jitter change through the delay compensation module, and excellent delay consistency is shown in ultra-wideband signal transmission; the defect that compensation devices such as a traditional piezoelectric ceramic optical fiber stretcher, an optical phase shifter, a cascade multi-stage optical switch and a motor space optical delay line cannot meet the requirements of large range, high precision, quick response and wide frequency spectrum compensation capability at the same time is overcome; that is to say, the link delay compensation scheme in the transmission system has large-range, high-precision, quick-response and wide-spectrum compensation capabilities, and is particularly suitable for optical fiber transmission links with high stability and consistency requirements on ultra-wideband signal transmission.

The invention discloses an optical delay line in a Fizeau type optical synthetic aperture imaging system. The Fizeau type optical synthetic aperture imaging system comprises a simulation light source subsystem, a sub-aperture variable baseline subsystem, a light combination imaging delay line, a light combination imaging subsystem, a light combination imaging variable baseline subsystem, a first optical path detection subsystem, a second optical path detection subsystem and the like. Wherein optical delay lines in the first optical path detection subsystem and the second optical path detection subsystem are consistent in structure, composition, function and performance, are symmetrically arranged on two sides of the system, and form an angle of + 49.1 degrees / -49.1 degrees with the horizontal plane; the optical delay line is applied to an optical path detection subsystem in a Fizeau type optical synthetic aperture imaging system composed of four sub-apertures, and is obliquely arranged relative to the horizontal plane, so that each optical path detection telescope can measure three optical path detection light beams at the same time; two sets of symmetrically arranged optical path detection subsystems are set up in the system, so that four-beam optical path difference detection can be realized, and the detection efficiency is high.

The invention discloses a method for measuring the intrinsic carrier mobility of a semiconductor material, and relates to the technical field of semiconductor material performance measurement. The method comprises the following steps: establishing a measurement system for the intrinsic carrier mobility of the semiconductor material; using an optical delay line to continuously change the relative time delay between the probe light and the pump light, obtaining the light intensity of the probe light under the action of the pump light and without the action of the pump light, testing to obtain a transient reflection dynamic spectrum of the semiconductor material, and extracting to obtain a Brillouin oscillation signal; calculating an electron deformation potential, a hole deformation potential and a semiconductor material elastic modulus based on the Brillouin oscillation signal; and calculating the intrinsic carrier (electron and hole) mobility of the semiconductor material based on the electron deformation potential, the hole deformation potential and the elastic modulus of the semiconductor material. Aiming at the lack of a method for experimentally measuring the intrinsic carrier mobility of a material at present, the measurement method disclosed by the invention fills the blank in the field.

A double-optical comb coherent Raman spectrum background noise suppression system for probe light delay regulation is characterized in that a first spectroscope for dividing laser emitted by an optical frequency comb light source module into probe light and pump light is arranged in a probe light delay regulation module, and an optical delay line is arranged to apply delay amount to the probe light; the characteristic that the attenuation time of coherent Raman spectrum signals is longer than that of background noise is utilized, detection light with delay amount is used for detection, the purpose of suppressing the background noise is achieved, the signal-to-noise ratio of a double-optical-comb coherent Raman spectrum measurement system is improved, and spectral signal distortion is suppressed.

The invention belongs to the technical field of quantum information science, and particularly relates to a multi-soliton time domain distribution representation device and method. According to the multi-soliton time domain distribution characterization method, the time delay of one arm of the HOM interferometer is changed through the adjustable light delay line to carry out coincidence measurement of HOM interference, and characterization of multi-soliton time domain features is achieved. All devices used in the stability test method are mature commercial devices, can be used in the fields of quantum communication, quantum calculation, quantum precision measurement and the like, and are beneficial to practical and commercialized development of light quantum information science and technology.

The invention discloses an array emission multi-beam forming integrated chip and a forming method, belongs to the technical field of phased arrays, and solves the problems that a large-scale array and a simultaneous multi-beam forming chip are multiple in control channels, large in loss, complex in network structure, sensitive to the environment and complex in control. Multi-wavelength optical signals are filtered and shunted by adopting the elliptical micro-ring array, the on-off of each path of signals is controlled through the optical switch in the adjustable optical delay line, and the delay amount of the delay line is adjusted according to the actual demand of the phased array system, so that the optical signals of each path can be subjected to independent delay control; on-chip synthesis of a plurality of transmitting beams can be realized at the same time, the requirement on the agility capability of the modulated optical carrier laser is low, and compared with the existing full delay line path or full micro-ring path, the multi-beam integrated circuit has more flexible routing control and multi-beam realization, and the integration level of the whole chip is improved.

The invention relates to the field of electromagnetic field technology and radio frequency signal testing, in particular to a radio frequency standard field generation system and method based on near-field beam forming, and the system comprises a control unit, a radio frequency signal generation unit, a radio frequency field control unit and a broadband radiation antenna array. The control unit carries a near-field electromagnetic wave synthesis mathematical model and is used for receiving a target field type setting requirement and calculating excitation amplitude and injection compensation phase required by each radiation unit configured in the broadband radiation antenna array; the radio frequency signal generation unit comprises a pulse modulation laser source and a plurality of semiconductor radiation units and is used for generating high-power programmable radio frequency signals; the radio frequency field control unit comprises an optical delay line and an FPGA matrix and is used for performing amplitude and phase regulation and control on the high-power programmable radio frequency signal output by the radio frequency signal generation unit; and the broadband radiation antenna array is used for receiving the regulated radio frequency signal and radiating the regulated radio frequency signal to the near-field space of the darkroom, and a target field pattern is formed through multi-unit electric field vector superposition.

The invention discloses a high-precision optical fiber link delay measuring device and method, and belongs to the technical field of optical fiber transmission. The device comprises a first signal source for outputting a sinusoidal signal; the second signal source outputs a 1pps pulse signal; the atomic clock is used for synchronizing the signals; the optical signal transmitting module mixes the two signals, modulates the two signals into an optical signal and transmits the optical signal to an optical fiber link; the tunable optical delay line is used for compensating delay jitter of the optical fiber link; the Faraday polariscope is used for reflecting light signals; the photoelectric detector is used for converting optical signals into electric signals; a first band-pass filter separating a sinusoidal signal from the electrical signal; the feedback control module is used for controlling the tunable optical delay line; the first data acquisition and processing module is used for obtaining a wide-range delay result; and the second data acquisition and processing module is used for obtaining a small quantity of high-precision delay results. According to the invention, the high-precision time delay of the optical fiber link can be obtained by obtaining a wide-range time delay result and obtaining a small amount of a high-precision time delay result.

The invention discloses a reflective pumping detection nondestructive testing device and method capable of saturatively absorbing uniformity in a mirror surface. The device is based on a wavelength degeneracy pumping-detection principle, and comprises a femtosecond laser source, a beam splitter, an optical delay line, a double-frequency optical chopper, a two-dimensional precision translation stage, a coaxial focusing system, a spatial filtering diaphragm arranged in a reflection light path, a photoelectric detector, a lock-in amplifier and a signal processing unit. According to the method, different point positions of a sample are accurately positioned through a two-dimensional translation stage, a nonlinear differential reflectance dynamic curve of each point is measured under low power, the maximum differential reflectance and the carrier lifetime are extracted as characteristic parameters, the spatial relative standard deviation of the characteristic parameters is calculated, and lossless and quantitative in-plane uniformity evaluation is realized. According to the method, the interference of the pump light is effectively filtered through the space filtering diaphragm, the signal-to-noise ratio is remarkably improved in combination with the phase-locked amplification technology, and the problem that the nonlinear optical performance uniformity of the saturable absorber mirror cannot be quantitatively evaluated through a traditional method is solved.

The invention relates to the technical field of photon computing networks, in particular to a system for realizing different-order matrix operation based on a single dispersive medium, which comprises a multi-wavelength light source, a modulation processing unit, a micro-ring array unit, a single dispersive medium unit and an acquisition processing unit which are connected in sequence, a single dispersive medium unit is used to carry out delay processing on each weighted modulation optical signal, and the delay duration of each weighted modulation optical signal is controlled. Therefore, the calculation result of convolution calculation performed on the first matrix by the second matrix can be obtained after summation processing is performed on the optical signal intensities of the delay weighted modulation optical signals on the same time domain, the calculation efficiency of matrix multiplication is greatly improved, and meanwhile, a single dispersive medium is introduced to replace a traditional optical delay line. The size of the optical computing integrated system is reduced, and the cost is reduced.

The invention provides a large-output-window analog correlator based on an optical frequency shift loop and an implementation method of the large-output-window analog correlator. Relates to the technical field of optical signal processing and the technical field of modern radars. The analog correlator comprises a continuous wave laser, a 1 * n optical coupler, n optical frequency shift loop structures which are connected in parallel, and a DSP processing module which are connected in sequence; the n optical frequency shift loops are the same in structure, and each optical frequency shift loop comprises a 1 * 2 optical coupler, two parallel Mach-Zehnder modulators, an optical delay line, a bidirectional optical frequency shift loop, a coherent detection module and an ADC module; according to the invention, expansion of an output window of the correlator can be simulated based on an optical frequency shift loop, relative group delay of electro-optical modulation signals is reasonably adjusted, correlation results output by each structure are enabled to be continuous in sequence and frequency domain splicing is carried out, n-time expansion of the output window of the correlator is obtained, and the system has a wide application prospect. The system has the advantages of capability of performing related processing on various types of signals, large bandwidth, large output window, high signal processing speed and reconfigurable system.

The application discloses a quantum random number generator based on feedback adjustment of a comparator threshold value and a random sequence generation method. The quantum random number generator comprises a superluminescent diode, a filter, an erbium-doped fiber amplifier, a fiber coupler with a coupling ratio of 50:50, an optical delay line, a first beam splitter and a second beam splitter with the same splitting ratio, a first optical power meter and a first photodetector connected with the first beam splitter, a second optical power meter and a second photodetector connected with the second beam splitter, a microcontroller connected with the first optical power meter and the second optical power meter, and a comparator connected with the microcontroller, the first photodetector and the second photodetector. The first photodetector and the second photodetector are connected with the comparator through a differential circuit. The application adjusts the threshold voltage to offset the influence of the output characteristics of a light source on the output random number.

The present invention discloses an optical delay line structure, including an outer housing, an inner housing and a reflection assembly. The outer housing is connected to the inner housing and an optical fiber. The reflection assembly is placed on the inner housing. The inner housing can move axially on an outer housing thread part of the outer housing so as to change the light path between the optical fiber and the reflection component. The reflection assembly includes a mirror holder, a reflection mirror, a plurality of fixing screws and a plurality of adjusting screws. When at least one of the adjusting screws is moved, the reflection mirror will tilt at different angles, thereby changing the path and intensity of light wave.

A signal processing apparatus, a detection apparatus and a terminal device, which relate to the technical field of detection, and are used for reducing the costs and occupied spaces of optical delay lines. The signal processing apparatus comprises a first frequency modulation group (11), a second frequency modulation group (21) and an optical delay line (400); the first frequency modulation group (11) comprises a first frequency modulation photoelectric loop (110), a second frequency modulation photoelectric loop (210) and a polarization control element (300); the second frequency modulation group (21) comprises a third frequency modulation photoelectric loop (310); the polarization control element (300) is connected among the optical delay line (400), a first beam splitting element (112, 212, 312) in each frequency modulation photoelectric loop (110, 210, 310) and a frequency mixer (114, 214, 314) in each frequency modulation photoelectric loop (110, 210, 310), and is used for outputting optical signals (S11, S21, S31) in the three frequency modulation photoelectric loops (110, 210, 310) to the optical delay line (400) in orthogonal polarization directions, and outputting the delayed optical signals (S11 ', S21 ', S31 ') to the mixer (114, 214, 314) in each frequency modulation optoelectronic circuit (110, 210, 310). The signal processing apparatus can achieve the effect that the three frequency modulation photoelectric loops (110, 210, 310) share the same optical delay line (400), and reduce the number of optical delay lines (400) required to be provided in the signal processing apparatus, and the costs and occupied spaces of the optical delay lines (400).

The invention belongs to the technical field of optical measurement, and relates to an MEMS fatigue evolution law observation device based on off-axis digital holographic microscopy, which comprises a red light super-radiation light-emitting diode light source, a wire grid type beam splitter, an objective lens and a CCD, and is characterized in that a linear polarizer, a half-wave plate and the wire grid type beam splitter are fixedly arranged on a light path emitted by a red light super-radiation light-emitting diode; a half-wave plate, a beam expanding lens group, a plano-convex lens, a beam splitter prism, an objective lens and a sample table are fixedly arranged on an object light path in sequence, a reflector is arranged on a vertical light path, and an optical delay line, the beam expanding lens group and the plano-convex lens are fixedly arranged on a reference light path; after the reference light passes through the reflector and the beam splitter prism, the reference light interferes with the object light reflected by the beam splitter prism on the CCD and is observed. According to the invention, the hologram of the MEMS device under high-frequency vibration can be acquired, and the surface topography of the MEMS device is obtained through computer rapid phase unwrapping, so that the purpose of observing fatigue evolution of the MEMS structure in real time is achieved.

The present invention discloses a method and device for testing the linear deviation of a high-speed frequency-modulated signal. The high-speed frequency-modulated signal to be tested is modulated into the optical domain by a high-speed electro-optical modulator. A high-speed adjustable optical delay line is used to split the optical signal into two signals with differential delays. The mixed output is detected in the optical domain. After filtering out the down-converted signal and phase-detecting the low-frequency signal output by a DDS, a high-speed ADC performs data acquisition, reception, and analysis. By varying the delay of the high-speed adjustable optical delay line and the corresponding low-frequency signal frequency generated by the DDS, and performing multiple measurements, the sampled data is fitted with a polynomial to determine the linear deviation of the high-speed frequency-modulated signal to be tested. The present invention has a simple structure, high measurement accuracy, and is easy to implement.

The invention belongs to the technical field of optical precision measurement, and particularly discloses a lens thickness measuring device and method based on opposite coaxial light path interference, which utilizes a common light path design that a 1310nm broadband low-coherence light interference system and a 1550nm narrow-band high-coherence light interference system share one reference arm, and innovatively adopts an opposite coaxial light path structure on a sample arm, so that the thickness of a lens is measured. Meanwhile, interference signals on the front surface and the rear surface of a sample lens are effectively extracted, key parameter measurement of the center thickness of the lens is integrated on a coaxial light path, the structure is simplified, and the complexity of equipment installation and debugging is reduced; the low-coherence light is used for accurately positioning the position of each surface, the high-coherence light is used as a scale for accurately measuring the distance between the surfaces, and the center thickness of the lens is calculated in combination with a specific algorithm, so that non-contact rapid high-precision measurement is realized; in addition, a grating ruler straight stepping motor is introduced to drive a sample arm light path assembly, and measurement of the center thickness of a long-distance lens or a lens group is achieved on the premise that the original scanning range of the optical delay line is kept.

The present invention discloses a microwave photon signal frequency conversion method based on an optical delay line array, which loads a high-speed microwave signal onto an optical carrier to generate a microwave photon signal, separates the microwave photon signal into multiple channels using an optical beam splitter and applies different time delays through a tunable delay line array, and uses a unified low-frequency sampling waveform to sample and process different timing positions of each channel of signal, and finally frequency-converts one high-speed signal into multiple low-speed signals. The present invention can effectively solve the "electronic bottleneck" faced by traditional electronic systems in processing high-speed microwave signals, improve the microwave photon signal processing capability through time domain serial-to-parallel conversion, reduce the control difficulty of the sampling signal through a tunable all-optical delay line, solve the bottleneck problem of high-speed wireless communication signal processing, and finally provide a solution for high-frequency and ultra-high-frequency wireless communication applications based on microwave photon technology.

The present invention discloses a phase adaptive stabilization system (PASS) based on an ultra-high stability multi-channel optical fiber transmission technology, which includes a transmitting source system, a receiving system, a reference system, and a phase measurement system; the transmitting source system includes a signal source, an ultra-high stability multi-channel optical fiber transmission system, and a transmitting antenna; the receiving system includes a receiving antenna, an amplifier, a mixer, an attenuator, etc.; the reference system includes a signal source, a frequency multiplier, a mixer, etc.; the phase measurement system includes a band-pass filter, an analog-to-digital converter, a digital correlator, a computer, etc. The ultra-high stability multi-channel optical fiber transmission system adopted by the present invention has the advantages of low loss, high stability, and anti-electromagnetic interference when transmitting optical signals over a long distance for a long time; through the remote reflection signal, the change in the signal phase caused by the disturbance of the transmission optical fiber can be detected in real time, and then the real-time phase compensation is carried out by feedback controlling the variable optical delay line, thereby realizing the ultra-high stability of the transmission signal phase.

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator and a stabilizing method thereof. The oscillator is provided with a long ring and a short ring and comprises a stabilizing device; the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher, a motor space light delay line and a second piezoelectric ceramic optical fiber stretcher; generating two optical probe signals; the first optical probe signal is converted into a first electric probe signal through the long ring; a second optical probe signal is converted into a second electric probe signal through the short ring; an electric probe signal is output after being subjected to detection, coupling and power division; the two frequency mixers respectively carry out homodyne frequency mixing on the electric probe signal and the phase-shifted and non-phase-shifted radio frequency signals to generate a zero-frequency error signal; the two phase-locked loops generate compensation control signals according to the error signals; the control signal adjusts an optical fiber delay line; the stability of the two loops is ensured, the problem of combined signal frequency drift caused by neglecting short-loop delay change is solved, the coherence requirement on optical signals is avoided by electric domain combination, and smooth tuning of the output radio frequency signal frequency is realized.

The application discloses a kind of background noise suppression systems of dual optical comb coherent raman spectrum of probe light delay control, by setting the laser that light frequency comb light source module is emitted into probe light and pump light by first beam splitter in probe light delay control module, and setting optical delay line is applied to the probe light with delay amount, utilize the characteristics that the decay time of coherent raman spectrum signal is longer than the decay time of background noise, probe using probe light with delay amount, realize the purpose of inhibiting background noise, it is beneficial to improve the signal-to-noise ratio of dual optical comb coherent raman spectrum measurement system, inhibits spectrum signal distortion.

Devices and / or methods provided herein relate to providing conversion of photons between an optical domain and a microwave domain. An electronic structure can comprise a resonator assembly comprising a microwave resonator and an optical resonator, an optical pump waveguide that transmits an optical pump input to the resonator assembly, and an optical signal waveguide, separate from the optical pump waveguide, that transmits an optical signal relative to the resonator assembly. The electronic structure further can comprise a microwave signal waveguide that transmits a microwave signal relative to the resonator assembly. The optical pump waveguide can comprise a delay portion that delays receipt of the optical pump input to the resonator assembly through the optical pump waveguide to a time after reduction of a majority of decoherence of the resonator assembly caused by scattering of a portion of the optical pump input, which portion does not enter the optical pump waveguide.

This invention discloses a distributed acoustic wave sensing system and all-optical integration method based on an optical neural network, relating to the fields of fiber optic sensing and artificial intelligence. The system comprises a DAS optical path integration component, an external connection component, and a signal processing integrated chip. The system combines an integrated optical delay line, a quasi-three-port detection structure, and a pure optical neural network module to achieve all-optical integration of the DAS sensing system and pure optical signal processing. This system offers advantages such as reduced photoelectric conversion, enhanced parallel processing capabilities, increased processing speed, reduced energy consumption, improved system stability, and a simplified system architecture.

This invention discloses a delay compensation device, a delay compensation method, and a phased array laser terminal. Multiple transmitting optical paths, a sampling and monitoring module, and a phased array antenna are sequentially connected in communication. Each transmitting optical path includes a first optical delay line and a first high-speed phase shifter. The sampling and monitoring module determines a first delay control parameter and a first phase control parameter, or a second delay control parameter and a second phase control parameter, based on the optical path difference. The first optical delay line performs first optical path difference delay compensation on the laser beam. The first high-speed phase shifter performs first phase difference delay compensation on the laser beam. The phased array antenna performs second optical path difference delay compensation and second phase difference compensation on the laser beam based on the second delay control parameter and the second phase control parameter. In this embodiment, the delay compensation of the laser beam using the first optical delay line, the first high-speed phase shifter, and the phased array antenna solves the phase jump and wavelength dispersion problems in phased array communication and improves communication capacity.

An optical system, capable to admit a light beam, the optical system comprising: a plurality of reflectors configured to reflect the light beam, wherein each of the reflectors is configured to reflect an incident light beam such that the path of the incident light beam and the path of the reflected light beam are parallel to each other. Each of the reflectors has a reflection center axis positioned centrally between the path of the incident light beam and the path of the reflected light beam. At least two of the reflectors are arranged relative to each other such that their respective reflection center axes do not overlap, thereby enabling the path of the light beam to pass at least one of the at least two of the reflectors multiple times.

The present invention relates to the field of photon computing network technology, and in particular to a system for realizing matrix operations of different orders based on a monochromatic dispersive medium. The system comprises: a multi-wavelength light source, a modulation processing unit, a micro-ring array unit, a monochromatic dispersive medium unit and an acquisition processing unit connected in sequence. The monochromatic dispersive medium unit is used to perform delay processing on each weighted modulated optical signal, and by controlling the delay time of each weighted modulated optical signal, after summing the optical signal intensities of each delayed weighted modulated optical signal in the same time domain, the calculation result of the convolution calculation performed by the second matrix on the first matrix can be obtained, which greatly improves the calculation efficiency of the matrix multiplication operation. At the same time, the monochromatic dispersive medium is introduced to replace the traditional optical delay line, which is conducive to reducing the size of the optical computing integrated system and reducing the cost.

The present invention provides a single sideband signal generator, comprising: a modulator configured to generate a first modulated optical signal and a second modulated optical signal having the same amplitude; and the sideband suppression light circuit based on the first light delay line is used for generating a full-carrier single-side-band signal, and / or the sideband suppression light circuit based on the second light delay line is used for generating a carrier-suppressed single-side-band signal. The present invention simplifies the structure by saving half the space occupied by redundant signal electrodes, and also reduces the RF power consumption by half by removing an RF mixer. The provided single side band (SSB) signal generator has the advantages of compact structure, low cost and energy conservation. By reasonably designing the length of the optical delay line, the generator can be easily expanded to a higher frequency range on the premise of not needing extra cost.

The utility model relates to the technical field of optical communication, in particular to an expanded bandwidth heterodyne coherent receiving mechanism without an optical filter. Comprising a first optical splitter module and a second optical splitter module, the first optical splitter module is connected with a first polarization beam splitter module and a second polarization beam splitter module, the second optical splitter module is connected with a third optical splitter module and a fourth optical splitter module, and an optical delay line module is arranged between the output end of the second optical splitter module and the fourth optical splitter module. The output ends of the first polarization beam splitter module, the second polarization beam splitter module, the third optical splitter module and the fourth optical splitter module are all connected with an optical coupler module, and the optical coupler module is connected with an electric signal recombination module through a balanced photoelectric detector module. The receiving mechanism provided by the utility model not only saves an optical filter and a 90-degree optical mixer, but also can realize heterodyne coherent detection with low hardware complexity and an internal difference detection coherent receiver with spectral efficiency approaching a standard by only needing half of signal optical bandwidth.

By arranging light source, optical chip, interferometer, photoelectric detection module, sample acquisition module and data processing module, wherein light source is connected to interferometer by optical chip, while both reference path and sample path of optical chip have optical delay line arranged respectively, and optical delay lines are continuously adjustable; optical chip is configured to divide detection light into reference path signal light and sample path signal light, and transmitting reference path signal light and sample path signal light to interferometer by optical delay line continuously adjustable respectively. Comparing with traditional mechanical style TD-OCT system having problem of scanning rate slow, present solution replaces a mechanical movement of reference path in prior art by optical delay lines continuously adjustable, which not only improves scanning rate, but also has smaller volume.

The present invention belongs to the field of fiber optic chemical sensing technology, specifically a liquid refractive index measurement device based on chaotic Brillouin dynamic gratings. This device solves the problem of existing inability to perform distributed liquid refractive index analysis and the requirement that traditional fiber gratings (FBGs) must be permanently inscribed in the optical fiber for chemical refractive index analysis. The device comprises a chaotic light source, a first optical splitter, an electro-optic modulator, a first optical amplifier, a tunable optical filter, a first circulator, a sensing optical fiber, a variable optical delay line, a second optical amplifier, a light combiner, a tunable laser, an acousto-optic modulator, a third optical amplifier, a photodetector, and a bandpass filter. The sensing optical fiber is disposed in the liquid to be measured. Compared with traditional fiber grating refractive index measurement devices, the present invention is ready for use and can perform distributed measurement, overcoming the shortcomings of traditional fiber grating refractive index measurement devices, which require permanent grating inscription in the optical fiber and are almost entirely limited to point measurements.