19 results about "Photomixing" patented technology

The application provides a distributed optical fiber acoustic wave sensing system and a pattern recognition method. The application relates to the fields of optical fiber sensing and pattern recognition, and the system comprises the following steps: continuous coherent light emitted by a narrow-line-width laser is split into two paths by a beam splitting fiber coupler, one path is used as local reference light, and the other path is used as probe light; the probe light is modulated into optical pulses in an acousto-optic modulator driven by a waveform generator, and the optical pulses are injected into a measured sensing optical fiber through a fiber loop; Rayleigh backscattering light returned through the measured sensing optical fiber is mixed with the local reference light through the fiber loop, and the mixed light is decomposed into two orthogonal polarized light beams in a polarization beam splitter and is transmitted to a first balanced photodetector and a second balanced photodetector respectively to be converted into electrical signals; and the two orthogonal interference electrical signals are synchronously collected by a data acquisition card and are sent to a host computer for demodulation. The application provides a new distributed acoustic wave monitoring method with high reliability and high generalization ability, and has extremely high engineering popularization value.

According to the overexposure grating diffraction laser spot image extraction method provided by the invention, multi-scale expansion and corrosion operation is adopted, so that large-area highlight operation is processed for an exposure image, background noisy points can be filtered out, useful information of diffraction spots can be reserved, useful spot information is distinguished from other information, and the image extraction efficiency is improved. Convenience is provided for a rear end to continue to recognize light spot information, and the problem of mixed distinguishing of laser captured by a photoelectric detector and stray light under the condition that laser energy is too high is solved; in other words, stray light and noise light signals mixed in the original image are subjected to expansion corrosion and other preprocessing before the light spot image is processed, and the processing difficulty of a rear-end circuit and the design complexity can be reduced; a light spot image is more clearly divided from a preprocessed grating diffraction type laser light spot image in an exposure state, and subsequent laser point location extraction is carried out so as to identify the wavelength type of laser.

To provide a photomixer that can achieve at least one of miniaturization and increased output of electrical signals. [Solution] The photomixer 10 according to this disclosure includes a light receiving unit 11 that receives incident light and converts it into an electrical signal having a predetermined frequency, an amplification unit 12 that amplifies the electrical signal output from the light receiving unit 11, and a coaxial connector 13 that receives and outputs the electrical signal amplified by the amplification unit 12.

The invention relates to an optical device configured for measuring fluorescence and absorbance in immunoassays and wet chemistry, comprising:-an illuminator channel (26) comprising at least one excitation source (28),-a detector channel (34) comprising at least one sensor (36),-a cuvette (130) comprising a sample (132) between the illuminator channel (26) and the detector channel (34), -an optical light mixer (38) between the illuminator channel (26) and the cuvette (130) and an optical splitter (40) between the cuvette (130) and the detector channel (34).

Light-emitting diode module, LED module, which is configured to emit white light, wherein the LED module has: a blue light-emitting diode (30) configured to emit blue light with a first peak wavelength in a range of 420 nm to 465 nm; at least one wavelength conversion material (54, 56) configured to convert part of the blue light into converted light of another wavelength; and a near-infrared wavelength conversion material (58) configured to be excited by the blue light of the blue light-emitting diode (30) to emit an additional light with a second peak wavelength in a range of 740 nm to 900 nm and a full width at half maximum (FWHM) of 120 nm or less, wherein the near-infrared wavelength conversion material (58) Ca(Al 12-x-y ,Ga y )O 19 :xCr 3+ (0≤x≤1, 0≤y≤6) exhibits, where the converted light, another part of the blue light, and the additional light combine to form the white light, and wherein a spectrum of the white light thus formed has a peak intensity in the range of 740 nm to 900 nm, and the peak intensity is greater than or equal to 4.5% of a peak intensity in a blue band from 420 nm to 465 nm.

The invention provides a gas temperature rapid resolving method based on a heterodyne phase-sensitive dispersion spectrum technology, which comprises the following steps of: outputting continuous frequency sweeping laser by adopting two tunable lasers with different center frequencies, and modulating the continuous frequency sweeping laser into three-frequency mixed laser through high-frequency light intensity; after the three-frequency laser passes through the gas to be detected, the light intensity is converted into an analog voltage signal by a photoelectric detector, and phase shift caused by the gas to be detected is extracted by using a phase discriminator; discrete wavelets and cubic spline interpolation are used to obtain a phase shift curve with equally spaced frequencies; then, Fourier transform and Hilbert inverse transform are sequentially carried out on the curve to obtain a three-frequency laser mixed absorption spectrum, and a laser absorption spectrum is obtained by combining the displacement characteristic of Fourier transform; and finally, calculating the integral absorption area under the two center frequencies so as to obtain the temperature of the measured gas. According to the invention, high-sensitivity rapid gas temperature detection is realized, laser power fluctuation can be resisted, background radiation noise can be effectively inhibited, and the method has an important application prospect in the field of combustion gas flow temperature detection.

The present invention relates to an elongated linear lighting device (1) having a light mixing chamber (2) that is delimited by first and second opposite longitudinal sides (3, 3') and by first and second opposite transverse sides (4, 4'). The elongated linear lighting device (1) also has a light source (5) arranged on the first longitudinal side (3) of the light mixing chamber (2) and configured to emit light towards the second longitudinal side (3') of 5 the light mixing chamber (2), where a direct light exit window (6) is arranged. The elongated linear lighting device (1) further has a linear reflector (7) with a longitudinal extension (X) in a direction parallel to an axis of elongation of the light mixing chamber (2), and a transversal extension (Y) in a direction perpendicular to the axis of elongation. The linear reflector (7) has two branches (8, 8'), each having a first reflector portion (7') with a first reflector surface 0 (13, 13') and a second reflector portion (7'') with a second reflector surface (14, 14'), which are connected at a vertex (9, 9'). The branches (8, 8') of the linear reflector (7) are arranged along the transverse sides (4, 4') of the light mixing chamber (2) such that the vertices (9, 9') are arranged in the light mixing chamber. The first and second reflector portions (7', 7'') of the linear reflector (7) are arranged at an angle relative to each other, the angle being larger 5 than 0 degrees and smaller than 180 degrees. The first reflector surface (13, 13') faces towards the first longitudinal side (3) of the light mixing chamber, and the second reflector surface (14, 14') faces towards the second longitudinal side (3') of the light mixing chamber.

The application provides an optimization method, device and equipment of a cold atom magneto-optical trap system and a medium, effectively solving the problems of high difficulty in operation and adjustment, large volume and high power consumption of the magneto-optical trap system. The method comprises: processing laser generated by the laser respectively to obtain re-pumping light and pumping light; mixing the re-pumping light and the pumping light to obtain cooling light, and irradiating the cooling light on the grating chip, and cooperating with the nested anti-Helmholtz coil to obtain a trapped cold atom group; fusing the trapped cold atom group and a pre-set background image to obtain a background image with a cold atom group, so as to obtain an original cold atom group photo and a background image photo; performing operation based on the background image photo and the original cold atom group photo to obtain an operation result, so as to complete optimization of the cold atom magneto-optical trap system based on the operation result.

The application discloses a nitrogen-assisted bidirectional double-color argon laser generation method and device, and belongs to the technical field of ultrafast lasers. 12 W / cm 2 The method comprises the following steps: focusing linearly polarized pulse pumping light with a central wavelength of 261±1 nm in a mixed gas containing nitrogen and argon, and the corresponding peak power density is greater than 10 The method is simple, only needs to generate specific pumping light and focus the pumping light in the mixed gas containing nitrogen and argon, and then bidirectional double-color cascade argon laser can be obtained, for example, the air can be directly excited to generate argon-air laser, and the method is simple and widely applicable.

The invention discloses a constellation satellite ranging correction method based on a microwave laser hybrid link, and belongs to the technical field of satellite navigation ranging. The method solves the problem that the distance measurement precision of an existing method is limited. According to the method, interpolation is carried out on the laser ranging information by adopting an interpolation method, high-precision laser ranging information can be virtualized at the moment without laser information, then the laser ranging information and microwave ranging information at each moment are fused on the basis of the optimal fusion theory, the ranging result at each moment can be fused with the laser ranging information, and the accuracy of the laser ranging information is improved. High-precision distance measurement between satellites is realized, and the distance measurement precision is obviously superior to that of a single observation source. According to the method, the distance measurement fusion result is converted into the position of the slave satellite in the reference coordinate system, a relative motion model of the master satellite and the slave satellite based on the CW equation is adopted, and a Kalman filtering multi-source information fusion algorithm is adopted based on the model, so that various errors caused by nonlinearity are avoided. The method can be applied to the technical field of satellite navigation ranging.

Coherent detection methods, with an optical source emitting frequency chirped or wavelength swept light, split optical beam into two main paths: target path and reference path (local oscillator). Target path sends portion of the light to environment for sensing. Reference path sends portion of the light to a path that generates a known propagation delay. Light returning from both paths are mixed together (interferometer) to generate a beat signal that represents the propagation delay difference between the two paths. The beat signals obtained in these systems need to be calibrated for removing any imperfections and nonlinearities due to frequency chirping or wavelength sweeping process issues or any other noise sources. Current disclosure describes coherent detection systems and methods that calibrate out beat signal imperfections using any internal reflections returning from target path without adding an additional calibration interferometer or detectors.

According to an aspect of the present inventive concept, there is provided a laser system for generating a frequency modulated continuous wave (FMCW) optical signal.SOLUTION: The system (100) includes a tunable laser (110) for generating an FMCW optical signal (112), an optical hybrid coupler (122) for receiving a portion (114) of the FMCW optical signal (112) and for, based on a difference between first and second signals (114a, 114b) formed by splitting the portion (114) of the FMCW optical signal (112): And a control unit (130) configured to estimate, based on the at least two angular diversity signals (124), a compensation required to adjust a non-linearity of the frequency chirp of the tunable laser (110) and to output a corresponding control signal (132) to the tunable laser (110), wherein the control signal (132) is configured to improve the linearity of the frequency chirp.SELECTED DRAWING: Figure 1

The disclosure regards a signal mode-matching system for coherent optical receivers, the system comprising, an optical hybrid for receiving an optical signal, and comprising a local oscillator, the optical hybrid configured to separate the optical signal to a plurality of orthogonal components, and configured to interfere the plurality of orthogonal components of the optical signal with the local oscillator, a pair of photodiodes per orthogonal component, configured for detecting the outcomes of the interference for each corresponding orthogonal component, each photodiode of the pair generating a primary photocurrent, each pair of photodiodes combined such that the two primary photocurrents of each pair of photodiodes generate a combined photocurrent, a plurality of variable optical attenuators, one for each photodiode, each variable attenuator positioned between the optical hybrid and its corresponding photodiode, and an analog to digital converter configured to digitize each of the plurality of combined photocurrents corresponding to the orthogonal components, wherein the signal mode-matching system is configured to equalize the detection of each orthogonal component by performing frequency dependent gain-balancing in the digital domain using the output of the analog to digital converter, and controlling the variable optical attenuators to maximize the equalization of the optical efficiencies of the plurality of orthogonal components, thereby maximizing mode-matching among the different orthogonal components.

The application discloses a five-channel light-emitting device which emits mixed light, wherein the mixed light is mixed by sapphire blue light, mint color light, cyan light, white light and red light; the color temperature of the white light is 4000K; the main wavelength of the sapphire blue light is 445-475nm, the peak wavelength is 440-470nm, and the half-peak width is 15-30nm; the main wavelength of the mint color light is 535-575nm, the peak wavelength is 528-568nm, and the half-peak width is 80-150nm; the main wavelength of the cyan light is 491-511nm, the peak wavelength is 488-508nm, and the half-peak width is 20-60nm; the main wavelength of the white light is 570-610nm, the peak wavelength is 600-640nm, and the half-peak width is 150-225nm; and the main wavelength of the red light is 615-640nm, the peak wavelength is 620-650nm, and the half-peak width is 15-35nm. The application mainly relates to the technical field of light sources.

Provided is a photomixer capable of achieving at least one of reduced size and increases output of an electric signal. A photomixer 10 according to the present disclosure comprises a light receiving unit 11 that receives incident light and converts the light into an electric signal having a predetermined frequency, an amplification unit 12 that amplifies the electric signal output from the light receiving unit 11, and a coaxial connector 13 that receives and outputs the electric signal amplified by the amplification unit 12.

The utility model belongs to the technical field of non-polarization-maintaining lasers, and particularly relates to a non-polarization-maintaining fiber laser system. According to the non-polarization-maintaining optical fiber laser system, light output by the non-polarization-maintaining optical fiber laser serves as infrared fundamental frequency light (which can be continuous or pulse) and is transmitted to the laser head through the optical fiber, a second harmonic crystal can be arranged in the laser head, and infrared light is converted into green light to be output through the second harmonic crystal; a second harmonic crystal and a third harmonic crystal can also be integrated in the laser head, the second harmonic crystal converts the infrared light into green light, then the infrared light and the green light are mixed and enter the third harmonic crystal for sum frequency action, and ultraviolet output is obtained. In addition, flexible movement in an actual application scene is facilitated through optical fiber transmission, and the laser output head is integrated with a nonlinear crystal and can directly output green light or ultraviolet light.

The invention discloses a terahertz and space laser hybrid modulation coding and decoding communication system, which relates to the technical field of optical communication and terahertz communication and comprises a hybrid modulation coding module, a terahertz and space laser parallel link transmitting module, a terahertz and space laser parallel link receiving module and a hybrid demodulation decoding module. The invention further discloses a terahertz and space laser hybrid modulation coding and decoding communication method, hybrid modulation coding and decoding are carried out on a terahertz link and a space laser link based on the polarization code, and only one pair of coding and decoding devices is used for completing the coding and decoding work of the terahertz and space laser link. And the rate self-adaption is realized by dynamically adjusting the modulation formats and the transmission ratio of the two links, so that the complementary transmission capability of the two links under different extreme weather conditions can be fully exerted, and the effective capacity and the reliability of the system are improved.

The invention discloses a microwave photon channelized receiver based on double optical combs and an image rejection mixer. The microwave photon channelized receiver comprises a laser, an MZM, a DPMZM, a frequency multiplier circuit, an optical frequency shifter, a 90-degree optical hybrid coupler, a WDM, a BPD, a 90-degree phase shifter and a radio frequency signal. An optical carrier is divided into an upper path and a lower path by an optical coupler, the upper branch optical carrier generates four ultra-flat optical frequency combs with the interval of 80GHz through an MZM1 driven by a frequency multiplication signal, the generated four-line optical frequency combs enter an MZM2 to carry out carrier suppression double sideband modulation (CS-DSB), and signals to be received are modulated on two sidebands of the optical frequency combs to serve as signal optical combs; in the lower branch, the optical carrier is firstly injected into the optical frequency shifter for frequency shift, and then enters the DPMZM to generate a seven-line optical frequency comb as a local oscillator optical comb; the microwave photon mirror image rejection channelized receiver has the advantages that mirror image interference signals are effectively suppressed by the microwave photon mirror image rejection channelized receiver scheme, radio frequency broadband signals with the center frequency being 20 GHz and the bandwidth being 7 GHz are efficiently received, and the mirror image rejection ratio is larger than 25 dB.