1377results about "Optical measurements" patented technology

The present disclosure is of an atmospheric characterization system that has a central processing board that has a first and a second communication interface. Further, the atmospheric characterization system further has a first precision temperature sensor that is communicatively coupled to the central processing board via the first communication interface and positioned a distance from a first side of the processing board, wherein the precision temperature measures a first temperature and transfers data indicative of the first temperature to the central processing board. In addition, the atmospheric characterization system has a second precision temperature sensor that is communicatively coupled to the central processing board via the second communication interface and positioned the distance from a second opposing side of the processing board such that the first precision temperature sensor and the second precision temperature sensor are equidistance from the processing board and a distance between the first precision sensor and the second precision sensor is a predetermined distance, r, and the second precision temperature sensor measures a second temperature and transfers data indicative of the second temperature to the central processing board simultaneously with the transferring of the first temperature. Additionally, the atmospheric characterization system has a processor that receives the first temperature and the second temperature and calculates a value indicative of atmospheric turbulence based upon the first temperature and the second temperature, wherein the value indicative of the atmospheric turbulence is used for designing, modifying, calibrating, or correcting an optical system.

The invention discloses a wavefront reconstruction method for improving the dynamic range of a Shack-Hartmann wavefront sensor. Belongs to the technical field of wavefront detection. According to the method, a new Shack-Hartmann wavefront detection method is needed, the effective dynamic range of a Shack-Hartmann sensor can be expanded on the premise that the hardware complexity is not remarkably increased, local mismatching accumulation can be avoided through a reasonable matching strategy, and the detection accuracy is improved. Therefore, high-precision and high-reliability wavefront reconstruction can be realized in a large-amplitude wavefront distortion scene. Comprising the following steps: S1, detecting by a Shack-Hartmann wavefront sensor to obtain a light spot distribution diagram H (x, y); s2, extracting a light spot centroid pixel-level position through a matched filtering algorithm; s3, calculating the sub-pixel-level position of the mass center of the light spot through Gaussian interpolation; s4, a mass center-subaperture matching relation is established through a Kuhn-Munkres algorithm; and S5, calculating the wavefront slope according to the corresponding relationship between the centroid and the sub-aperture, and then recovering the wavefront according to the wavefront slope.

The invention discloses a Hartmann wavefront sensor wavefront detection method and device based on sub-aperture time domain information windowing, and belongs to the technical field of wavefront detection.The method comprises the steps that a light spot array image of a Hartmann wavefront sensor with dynamically fluctuating light intensity is collected; segmenting effective sub-apertures according to the design arrangement of the Hartmann wavefront sensor sub-apertures, and obtaining the mass center positions and signal-to-noise ratios of the preorder multi-frame effective sub-apertures; calculating the signal-to-noise ratio of each effective sub-aperture of the current frame of light spot array image by using the same method as the step 1; selecting a light spot positioning algorithm according to the signal-to-noise ratio of each effective sub-aperture obtained in the step 2; and obtaining a slope vector of the detection wavefront of the current frame according to the centroid positions of all the effective sub-apertures of the current frame, and reconstructing the wavefront by adopting a wavefront restoration algorithm. According to the invention, the wavefront detection precision of the Hartmann wavefront sensor in a complex environment can be improved, the sudden change of the wavefront slope can be avoided by means of the time domain continuity constraint, and the system robustness is enhanced.

The invention relates to an optical phased array phase calibration method and device, an electronic device and a storage medium, and is applied to the field of optical detection.The optical phased array phase calibration method comprises the steps that a to-be-calibrated phase image is input into an optical phased array system, and a random disturbance phase image corresponding to the to-be-calibrated phase image is obtained; the random disturbance phase image is obtained by performing phase disturbance within a preset range on the to-be-calibrated phase image. Inputting the to-be-calibrated phase image and the random disturbance phase image into a target convolutional neural network model, and determining a target phase error of the to-be-calibrated phase; the target convolutional neural network model is obtained by training a preset convolutional neural network model based on the far-field training image pair; and calibrating the initial emission electric field of the to-be-calibrated phase image based on the target phase error. According to the invention, the problem that the accuracy of phase error calibration of an existing optical phased array needs to be improved is solved.

The invention discloses a weak measurement sensing method, device and system based on a coherent state. Local oscillation light and coherent state signal light are obtained. And inputting the signal light into the weak measurement unit by taking a coherent state as a pointer state based on a to-be-measured signal to obtain a quantum state of the signal light. The carriers selected by the weak measurement system are enriched, and the application range of the weak measurement technology is expanded. Heterodyne detection is carried out on a quantum state by using local oscillation light, and secondary amplification is carried out on a signal to obtain a detection result, so that high-sensitivity sensing on a tiny signal is realized. And acquiring the variation of the to-be-detected signal based on the detection result, and calculating to obtain a detection signal according to the variation. According to the invention, high-sensitivity detection is carried out on tiny physical quantities by adopting quantum resources, the application of a quantum sensing technology on the premise of high measurement precision is supported, and the advantages of the quantum resources are fully exerted.

The invention relates to the technical field of atmospheric optical measuring instruments, in particular to an atmospheric coherent length measuring device and a measuring method thereof, and the measuring device comprises a telescope, a focalizer, a primary mirror camera, a star guide mirror, a star guide camera, a PoE power supply communication module, a laser and a computer; the primary mirror camera is connected with the telescope through the focalizer; the focalizer is used for adjusting the focal length of the telescope; the star guide mirror, the PoE power supply communication module and the laser are arranged on the telescope; the star guide camera is connected with the star guide mirror; and the primary mirror camera, the guide star camera, the laser and the computer are all connected with the PoE power supply communication module. The method has the advantages that by adding the focalizer, better and faster focusing work is realized, the telescope obtains clearer fixed star light spot images, and atmospheric coherence length parameters can be calculated more accurately.

The invention relates to the technical field of adaptive optics, and particularly provides a wavefront detection system for a dark and weak target under a strong sky background, the wavefront detection system comprises a Shack-Hartmann wavefront sensor system and a wavefront detection processing unit, the Shack-Hartmann wavefront sensor system carries out wavefront detection on a short wave infrared band of 1.3-1.7 [mu] m, and the wavefront detection processing unit carries out wavefront detection on the short wave infrared band of 1.3-1.7 [mu] m. And the wavefront detection processing unit corrects a sub-aperture image obtained by detection through a weighted self-threshold local contrast algorithm, performs self-threshold operation on pixels in a center unit according to a gray scale ratio weight of the center unit and a background unit of the sub-aperture image, introduces an energy weight to eliminate PNHB noise, and reconstructs a centroid of the sub-aperture image. According to the invention, a Shack-Hartmann wavefront sensor system is applied to a short-wave infrared band, so that a sky background spectrum is effectively blocked, the target brightness is ensured, background light radiation photons received by a detector are reduced to the greatest extent, various noises and background interferences are inhibited by optimizing a threshold algorithm, and the wavefront detection precision is remarkably improved.

The invention relates to the technical field of optical communication related calculation, in particular to an experimental method and device for measuring a vortex beam orbital angular momentum spectrum based on coaxial interferometry, and the device comprises a helium-neon laser, a beam-expanding collimation system, a light splitting modulation assembly, a spatial light modulator, a phase polarization adjustment assembly and a CCD camera. A spatial light modulator is arranged on a light path of a Gaussian beam output by the helium-neon laser, and a CCD camera is arranged at the tail end of the light path of the beam modulated by the spatial light modulator; the beam expanding and collimating system and the light splitting and modulating assembly are sequentially and coaxially arranged on a light path between the helium-neon laser and the spatial light modulator, and the phase polarization adjusting assembly is coaxially arranged on a light path between the spatial light modulator and the CCD camera. According to the invention, stable coaxial interference of the vortex beam and accurate measurement of the orbital angular momentum spectrum can be realized by using a small amount of experimental equipment, and the construction difficulty of an experimental interference light path is greatly reduced.

The invention discloses a full-field non-contact health monitoring method for a large-scale structure. The method mainly comprises the following steps: S1, dividing monitoring sub-regions; dividing the to-be-monitored area into a plurality of to-be-monitored sub-areas; arranging a plurality of distributed channel discrete speckle interferometers to respectively and synchronously image and monitor each to-be-detected sub-region; s2, acquiring a speckle interferogram and a dual-channel color map; the monitored object is deformed; respectively collecting speckle interferograms and dual-channel color maps before and after deformation of the to-be-detected sub-region; s3, processing a speckle interferogram; processing the speckle interferograms before and after deformation, extracting a phase fringe pattern reflecting defect information of the to-be-detected sub-region, and determining a defect form; s4, splicing the monitoring data; splicing the two-color channel images shot by the sub-regions to be detected; and performing geometric transformation and fusion on the phase change information by using the two-color channel image splicing parameters obtained before and after splicing to generate full-field monitoring data, and obtaining the defect position and damage evolution of the monitored object.

The invention provides a spectrograph wavelength calibration method, device and equipment and a medium, and the method comprises the steps: obtaining the spectral data of a spectrograph at different temperatures, and obtaining the spectral data of the spectrograph at different temperatures according to the pixel positions of a characteristic wavelength point at different temperatures and the pixel position of the characteristic wavelength point at a preset reference temperature; determining the pixel position offset of the characteristic wavelength point at different temperatures, and calibrating the wavelength of the spectrograph according to the pixel position offset of the characteristic wavelength point at different temperatures; in the process of calibrating the wavelength of the spectrograph, the wavelength drift caused by the pixel position offset of the characteristic wavelength point at different temperatures is fully considered, the output error of the wavelength of the spectrograph is reduced, and the wavelength output accuracy of the spectrograph is improved.

A digital adaptive optics encoder module includes an input mounting flange, a collimating lens, a bandpass filter, digital adaptive optic elements, refocusing lens, an output mounting flange, and a housing. The input mounting flange is capable of attaching to a telescope. The collimating lens is capable of expanding light from a target to fill a plurality of primary apertures. The bandpass filter has a bandwidth ranging from about 40 nm to about 100 nm. The digital adaptive optic elements include the plurality of primary apertures, an optical spreader, a focusing optic, and a detector. The refocusing lens is capable of refocusing an output from the digital adaptive optic elements onto a sensor plane. The output mounting flange is capable of attaching to an output connection. The housing encloses all of the interior components of the digital adaptive optics encoder module.

The invention relates to an aspheric wavefront detection device and method based on multi-direction orthogonal lateral shear interference. The device is composed of a laser, a linear polarizer, a light splitting element, a reflector array, a two-dimensional orthogonal grating array, a light splitting system, a polarization phase shifting element and a CMOS camera. The method comprises the following steps: firstly, an antisymmetric continuation method is included, secondly, dynamic phase recovery and distortion compensation are adopted, Zernike polynomial local fitting is introduced, and self-adaptive compensation is carried out on high-order aberration (such as coma aberration and trefoil aberration) of an aspheric surface edge region. According to the method, the multi-direction orthogonal lateral shearing interferogram can be obtained through single measurement, and a high-precision, high-efficiency and high-robustness solution is provided for precise detection of the aspheric optical element through cooperation of an algorithm and hardware. The method is suitable for high-precision phase recovery in the fields of optical detection, microscopic imaging and the like, and is suitable for high-precision dynamic detection of complex optical elements such as off-axis aspheric surfaces, free-form surfaces and the like.

The invention discloses a multi-scanning-angle parallel phase calibration method for a waveguide grating antenna, and the method comprises the steps: receiving light emitted by a one-dimensional waveguide grating antenna with M units through a receiving screen disposed in a far field, and shooting a far-field image through a camera; n detection points # imgabs0 # with different scanning angles are arranged on the far-field image; any unit m of the one-dimensional waveguide grating antenna is selected as a control object, the phase of emergent light of the unit m is changed from 0 to 2 pi by the control voltage with the step length of # imgabs1 #, and the corresponding control voltage when the energy of a detection point # imgabs2 # at different scanning angles reaches the maximum value serves as the calibration voltage # imgabs3 # of the grating antenna unit m at different scanning angles. According to the method, parallel calibration of control voltages at different scanning angles of the waveguide grating antennas is realized in a mode of circularly applying voltages to each waveguide grating antenna, and the calibration efficiency of the phases of the waveguide grating antennas is greatly improved.

According to the single-frame high-quality shearing speckle interference phase extraction method and device, the quality of the obtained phase is comparable to that of a traditional multi-frame phase solution algorithm, and single-frame high-quality phase extraction of shearing speckle interference is completed. The method comprises the following steps: (1) making a data set; (2) constructing a neural network; (3) neural network training; (4) detecting the detected piece: when the detected piece is static, carrying out N-step phase shift method shooting to obtain N frames of speckle interferograms when the detected piece is static; applying an external force to the measured piece, and recording light intensity information by using a camera to obtain a frame of interferogram when the measured piece is deformed; (5) single-frame phase extraction: phase extraction is carried out according to an N + 1 time phase shift method, and on the basis of N frames of phase shift interferograms when the measured piece is static, phase extraction is carried out by using one frame of interferograms after the measured piece is deformed, so that low-quality phase distribution is obtained; and (6) phase repairing.

The invention relates to the technical field of optical measurement, and discloses a multimode fiber spatial coherence experimental analysis system and method.The system comprises an LED light source arranged in front of the front end face of a sapphire fiber, and an aperture diaphragm arranged behind the rear end face of the sapphire fiber; the beam expander, the collimating mirror, the beam splitter, the compensation plate and the second right-angle reflector are sequentially arranged behind the aperture diaphragm, the first right-angle reflector is arranged above the beam splitter, the plane reflector is arranged below the beam splitter, the focusing lens is arranged behind the plane reflector, and the photoelectric detector is arranged behind the focusing lens. According to the invention, phase imbalance caused by arm length difference of interference arms can be eliminated, the definition of interference fringes is improved, and the accuracy of a measurement result is enhanced.

The invention discloses a laser phase noise quantum random number generator which comprises a light source module, an unequal arm interference light path, a detection module, a sampling module, a control processing module and a driving module. The light source module generates light signals and outputs the light signals to the detection module through the unequal-arm interference light path, the detection module detects the intensity of the interference light signals, the sampling module carries out high-speed sampling on output results of the detection module, and sampling data of the sampling module is calculated and analyzed through the control processing module to obtain the size of phase drift. Then, an electric signal is generated through a driving module to load a compensation phase to the unequal arm interference light path to offset phase drift, so that the laser phase noise quantum random number generator reaches a stable state; and when the laser phase noise quantum random number generator reaches a stable state, the control processing module performs entropy evaluation and randomness extraction on the sampling data to generate a random sequence. Through the structural arrangement, the control precision and the feedback compensation speed are effectively improved.

The laser linewidth is an important parameter for characterizing the coherence properties of a single-frequency laser. The disclosure of this patent document provides techniques for characterizing laser spectral linewidths of single-frequency lasers in form of analytical formula in connection with the use of one or more Sigmoid functions of observation time by including various physical origins affecting the laser linewidths in addition to the natural linewidth caused by the spontaneous emission or quantum noise that can be described with an analytical expression known as the Schawlow-Townes-Henry formula. The disclosed methods for characterizing the laser linewidth caused by various factors in analytical formula can be advantageously used in various applications including designing an optical interferometer based sensing device using coherent laser light from a single-frequency laser.

The invention relates to a self-calibration atomic wavelength meter. The self-calibration atomic wavelength meter comprises a saturated absorption spectrum light path for locking a detection laser frequency on a cesium atom energy level transition line based on a saturated absorption spectrum; the double-peak spectrum light path scans the frequency of a coupled laser after the frequency of the detection laser is locked by a saturated absorption spectrum, and when the detection laser and the coupled laser jointly act on alkali metal atoms and are subjected to resonance excitation, an electromagnetic induced transparency effect is generated; when the detection laser is detuned, the detection laser and the combined laser jointly act on the alkali metal atoms to generate non-resonance excitation, a double-peak EIT spectrum with Doppler frequency shift is generated, and the wavelength measurement of the current detection laser can be completed based on the linear relation between the double-peak spectrum interval and the detuning amount of the detection laser. In addition, the double-peak spectrum interval is compared with the atomic energy level transition frequency, the difference between the double-peak spectrum interval and the atomic energy level transition frequency serves as an error signal to be fed back to the control end of the detection laser, the frequency of the detection laser is tuned to the reference frequency standard, and calibration of the wavemeter can be achieved.

Disclosed is a linear array scanning Brillouin scattering elastic imaging device. In the device, a signal generating system consists of a narrow linewidth continuous wave laser, a half-wave plate, a beam expander, a Y-direction scanning galvanometer, a microlens array, a pinhole array filter, a first plano-convex lens, a polarization beam splitter, a quarter-wave plate and a microscope objective. A signal receiving system consists of a microscope objective, a quarter-wave plate, a polarization beam splitter and an eight-channel optical collimator array. Each channel of an eight-channel spectrometer consists of an optical collimator, a convex lens, a scanning Fabry-Perot interferometer, a photomultiplier tube and an eight-channel photon collection card.

The invention discloses a laser system output stability detection and analysis device and method. The device comprises an optical property detection unit and an optical property analysis unit which are in light path connection. The optical characteristic detection unit comprises a spectroscope (20), a beam shrinking mirror (21), a position sensitive detector (22), a focusing lens array (23) and a CCD camera (24) which are sequentially connected through an optical path; the optical characteristic analysis unit comprises a processor (30) and a controller (31), the controller (31) receives a processing result of the processor (30), and when the processing result of the processor (30) exceeds a set requirement of the laser system, the controller (31) sends alarm information to the laser system (10). According to the invention, the information of the laser beam position, the laser beam pointing direction and the light beam wavefront change of the laser system is measured at the same time, the influence of the light beam wavefront change on the measurement of the laser beam position and the laser beam pointing direction is eliminated, and the measurement precision of the laser beam position and the laser beam pointing direction is improved.

The invention provides a structured light detection system and method based on photon-level single-pixel wavefront imaging, and belongs to the technical field of wavefront imaging. The problem of low detection sensitivity of a single-pixel wavefront imaging technology in extreme environment communication is solved; comprising a structured light generation module, a light beam transmission module and a structured light detection module, the structured light generation module is used for generating structured light carrying different topological charges, the structured light is remotely transmitted to the structured light detection module through the light beam transmission module, and the structured light detection module is based on a coaxial phase-shifting interference wavefront imaging principle. A long-distance transmitted structured light signal is processed by adopting a single photon detection technology and utilizing a digital micromirror device and a Hadamard mask modulation technology; according to the method, under 50m long-distance transmission, each mask only needs 30 photons on average to complete topological charge identification, the structured light identification accuracy can reach 96% or above, and the method is suitable for structured light detection under ultra-long-distance and extremely-weak light conditions.

The invention relates to an image phase shift evaluation and phase calculation method and system based on an image selection mechanism, and belongs to the technical field of optical measurement. The method comprises the following steps: acquiring an original video, and obtaining a reference interferogram group through an image acquisition module based on the original video; obtaining an initial position interferogram based on the reference interferogram group, optimizing the recombined interferogram based on the initial position interferogram through an anti-vibration algorithm, and outputting a recombined interferogram anti-vibration sequence; calculating a phase shift accuracy index value based on the recombined interferogram sequence, presetting a phase shift accuracy index threshold, and extracting and outputting the recombined interferogram sequence of which the phase shift accuracy index value is greater than the phase shift accuracy index threshold as the target interferogram group; and calculating a phase shift quantity of the target interferogram group through a phase calculation module, calculating a phase shift evaluation index based on the phase shift quantity, and judging and outputting final phase information through the index. And image phase shift evaluation and phase calculation based on an image selection mechanism are realized.

The invention relates to a zero calibration weak measurement high-sensitivity interval compensation method and system, and the method comprises the steps: collecting the light intensity data of two paths and four channels in a zero input state, solving the asymmetry caused by the loss difference of the channels through a weak measurement method, and carrying out the calculation of the asymmetry. And correcting the post-selection state and the compensation sensitivity of the system according to the intensity difference of the output projection to the horizontal polarization state and the vertical polarization state, calculating the phase offset of a high-sensitivity interval according to the loss difference of the four channels, generating a compensation phase, and modulating the center of the high-sensitivity interval to a working point. Compared with the prior art, high-sensitivity loss and high-sensitivity interval offset caused by system asymmetry can be corrected through phase compensation and post-selection state correction, it is ensured that a measurement system always works in an optimal sensitivity interval, the measurement sensitivity and stability of a photoelectric detection system under weak measurement are improved, and the measurement accuracy is improved. The method is suitable for application scenes with strict requirements on tiny signal detection.

The invention discloses a random two-step inclined phase shift wavefront detection method based on deep learning, and solves the problems of harsh requirements on a measurement environment and large measurement errors in the prior art. The method comprises the following steps: carrying out analogue simulation to obtain two interferogram databases; establishing a neural network model, and dividing the interferogram database into a training set and a test set; inputting the training set into the neural network model for training to obtain a trained neural network model; inputting the test set into the trained neural network model for testing, and outputting a wavefront phase calculation value; calculating an error between the wavefront phase calculation value and the wavefront phase simulation value until a new neural network model is obtained; and obtaining multiple frames of interference fringe patterns of the to-be-detected optical element, inputting the interference fringe patterns into the new neural network model, and outputting a real wavefront phase of the to-be-detected optical element, thereby realizing random two-step inclined phase shift wavefront detection based on deep learning. The method is simple in operation and high in measurement precision.

The invention discloses a Shack-Hartmann wavefront detector centroid calculation method and related equipment, and relates to the field of optical measurement, and the method comprises the steps: obtaining a light spot array grayscale image, detecting the local maximum value of each light spot, and dividing sub-aperture image regions corresponding to micro lenses one by one according to the local maximum value; extracting a gray matrix of each sub-aperture image region, respectively determining one-dimensional regions of a light spot main lobe in row and column directions, and intersecting to obtain a main lobe region; a main lobe area is deducted from the sub-aperture image area to form a threshold calculation area, and the maximum gray value of the threshold calculation area is selected as a threshold; and performing threshold reduction on pixels in the sub-aperture image area, setting a negative value to zero, and calculating the position of the mass center of the light spot based on the processed image. According to the method, sub-aperture adaptive threshold and local background removal are realized, weak light spot information loss caused by a unified threshold is avoided, and the precision of centroid calculation and wavefront restoration is improved.

Methods, devices and systems are described that enable improved determination of wavefront errors associated with light traveling through turbulent media, such as through the atmosphere. The described systems use a Rayleigh-Raman polychromatic laser guide star (RRPLGS) to measure the tilt at the wavelength of observation by making use of the dispersion of the refractive index of air and differential tilt measurements at multiple combinations of wavelengths based on the Rayleigh and Raman back-scattered light. The described RRPLGS systems have a number of advantages, including scalability of returned flux and flexibility in selection of short wavelengths, allowing for a combination of multiple tilt measurements, and enabling characterization of the turbulent media without relying on photons from the object of interest.

The invention provides a method and device for improving Hartmann wavefront measurement precision based on time sequence correlation characteristics, and belongs to the technical field of optical aberration measurement. According to the method, the time sequence correlation between a detection signal and a reference signal of each pixel point is calculated, an appropriate time sequence correlation threshold value is selected, the pixel points with high signal-to-noise ratios are screened to select light spot areas participating in centroid calculation, and the selected light spot areas are used to calculate the light spot centroid. According to the method, limitation in threshold selection and noise suppression can be avoided, the sensitivity degree of wavefront measurement precision to noise is reduced, and the wavefront detection precision and stability of the Hartmann wavefront sensor in the field of high-precision measurement are further improved.

The invention relates to a method for measuring the coherence length of a Shell model correlation structure light beam, which belongs to the field of laser space coherence measurement, and comprises the following steps: S1, calculating the coherence lengths # imgabs0 # and # imgabs1 # in x and y directions by using the analytic relationship between the coherence length of the Shell model correlation structure light beam and the spatial coherence modulus; s2, a double-aperture mask is arranged on a light beam shaping transmission path of the laser processing system, the aperture positions are symmetrical, the distance d is adjustable, and after light beams are focused, intensity signals # imgabs2 are collected at a focal plane detector; and S3, extracting an intensity signal # imgabs3 # to obtain a double-aperture interferogram, performing Fourier transform on the interferogram, establishing a corresponding relation between a low-frequency component in a frequency spectrum and a characteristic frequency of an aperture spacing d, and calculating to obtain a spatial coherence modulus # imgabs4 #. According to the invention, based on partially coherent light dual-aperture interference and Fourier spectrum analysis, a direct analytical relationship between the spatial coherence degree and the coherence length is established, and a new way is provided for beam quality control in laser processing.

An apparatus includes a spectrometer receiving an optical input signal that includes an input optical spectrum. The spectrometer includes a fiber laser cavity pumped by a first optical replica of the optical input signal that generates stimulated Brillouin scattering traveling in a direction opposite to a direction of the optical input signal. The first optical replica of the optical input signal excites at least one lasing mode in the fiber laser cavity. The at least one lasing mode respectively includes at least one lasing mode frequency. The at least one lasing mode frequency is offset by a respective Brillouin frequency shift from the respective at least one input frequency. The spectrometer also includes an optical heterodyne receiver. The optical heterodyne receiver generates the electrical output signal. The spectrometer outputs a measurement of the input optical spectrum based on the respective Brillouin frequency shift and the at least one input frequency.

A system and method are provided for characterizing a laser using a diffraction grating. The system includes a lens that projects diffraction patterns from the diffraction grating as an image of diffraction peaks onto a plane. Optical sensors then sense the diffraction peaks. A processor connected to the optical sensors applies the laser characterization method to determine the laser wavelength, irradiance and angle of incidence. In the method, the processor obtains the diffraction peak measurements from the optical sensors and applies a transform to arrange the diffraction peaks into a grid of regularly spaced peaks. The processor then applies convolution kernels to analyze the grid of regularized peaks to determine a wavelength, irradiance and angle of incidence of the laser.