1216 results about "Pulse light" patented technology

The invention discloses an automatic testing device and method for multi-directional tensile strength of textiles based on constant tension, and relates to the technical field of tensile strength detection.The automatic testing device comprises a rigid rack system, and a high-elastic fabric optical response mechanism is integrated on a double-stand-column portal frame of the rigid rack system; the fiber damage process is reflected through the light transmittance of light to the fabric and the light spot change; the high-elastic fabric optical response mechanism comprises a sealing light insulation assembly, a light source assembly and an imaging assembly. The light source assembly comprises pulse LED light source arrays arranged at equal intervals in the fabric stretching direction, a lampshade and a transverse movement driving unit. The problems that in the prior art, when the tensile strength of a fabric is detected, only the limit value when a sample is completely broken can be recorded, and microcracks generated by step-by-step failure of fibers in the stretching process cannot be captured are solved. The device has the advantages that when the tensile strength of the fabric is detected, the fiber fracture process in the fabric is directly reflected through the change of light spots formed by light penetrating through the fabric, and the like.

The invention discloses a control system of an intense pulsed light therapeutic apparatus, which relates to the technical field of therapeutic apparatus control and comprises a dynamic spectral energy adaptation module, a three-dimensional contact pressure field calibration module, a domain gradient temperature management module and a multi-mode safety interlocking module. Through a multispectral sensor and a convolutional neural network, a skin absorption coefficient is dynamically calculated, pulse light parameters are optimized, and accurate energy adaptation is achieved; the uniformity of a contact pressure field is adjusted and calibrated by using a pressure-sensitive matrix and an ANFIS network in combination with a mechanical arm; by means of an annular temperature sensor array and a finite element model, regional temperature monitoring and dynamic adjustment are achieved; and through a multi-stage interlocking mechanism and a multi-dimensional scoring model, the safety and comfort of the treatment process are ensured. The treatment effect, the individuation level and the intelligent degree of the intense pulsed light therapeutic instrument are remarkably improved, and a more efficient and safer solution is provided for clinical application.

The invention discloses a signal-to-noise ratio improvement method based on a multi-core optical fiber dual-channel distributed acoustic sensing system, and the method comprises the steps: carrying out the light splitting of light emitted by a narrow linewidth laser through a first coupler C1, enabling one path of light to generate a pulse signal through an acoustic optical modulator (AOM), enabling the other path of light to pass through a second coupler C2, and enabling the other path of light to pass through a second coupler C1; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; based on a dual-channel DAS system, a multi-core optical fiber is used as a sensing optical fiber, three cores and four cores of the multi-core optical fiber are connected in series to form two sensing channels, seven-core space division signals are multiplexed, the equivalent self-noise pressure suppression effect of the seven-core space division signals is analyzed, after noise correlation is removed through a time domain dislocation-frequency domain phase shift method, the signal-to-noise ratio gain can be increased to 8.65 dB, and the signal-to-noise ratio gain can be increased to 8.65 dB. And the detection capability of the system on low-frequency weak signals can be improved.

The invention discloses an equivalent self-noise pressure suppression method and device based on a multi-core optical fiber space division multiplexing signal, light emitted by a narrow linewidth laser is split through a first coupler C1, one path of light passes through an acousto-optic modulator AOM to generate a pulse signal, and then the pulse signal passes through a second coupler C2 to generate a pulse signal; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; based on the dual-channel DAS system, the multi-core optical fiber serves as the sensing optical fiber, three cores and four cores of the multi-core optical fiber are connected in series to form two sensing channels, seven-core space division signals are multiplexed, the equivalent self-noise suppression effect of the seven-core space division signals is analyzed, and the detection capacity of the system for low-frequency weak signals can be improved.

The invention relates to the technical field of optical fiber monitoring and maintenance, and discloses an optical fiber monitoring method, device and equipment, a storage medium and a computer program product, and the method comprises the steps: enabling pulse light of a preset period to be coupled into a to-be-detected low-loss optical fiber based on an optical fiber amplifier and a variable optical attenuator, and generating a backward scattering light signal; converting the backward scattering light signal into an electric pulse signal by using a single-photon detector, and counting the electric pulse signal by using a preset period as a period through a synchronous clock to obtain a counting result; adjusting the power of the variable optical attenuator according to a counting result, and drawing a target signal curve of the to-be-measured low-loss optical fiber based on an adjustment result; and analyzing the target signal curve to obtain a monitoring result of the to-be-measured low-loss optical fiber. The power is dynamically adjusted in different measurement sections, and the multi-section measurement results are superposed, so that the dynamic range of the single-photon optical time domain reflectometer is remarkably expanded, and the loss and dead pixels of the low-loss optical fiber can be reflected more comprehensively and accurately.

The invention provides a sensing system fusing optical fiber vibration and acoustic emission, a monitoring method and a device, and relates to the technical field of optical fiber sensing. The device comprises a light source module, a sensing optical fiber, a detection module and a controller, the light source module is used for respectively emitting modulation pulse light for vibration monitoring and continuous wave laser for acoustic emission monitoring; the sensing optical fiber is arranged along a monitored structure or area, and at least one optical fiber acoustic emission sensing head is connected to the optical fiber in series. The detection module collects Rayleigh scattering light and beat frequency signals at all positions in the sensing optical fiber through a circulator and a coherent light receiver, and optical signals are converted into electric signals; wherein the electric signals comprise vibration electric signals and acoustic emission electric signals; the signal processing unit carries out phase demodulation and envelope analysis processing on the collected vibration electric signals and acoustic emission electric signals so as to obtain vibration waveforms and acoustic emission event space-time information along all points of the optical fiber. According to the invention, a monitoring task fusing vibration and acoustic emission can be accurately completed.

The invention discloses a tunable excited Raman spectrum microimaging method and device, and belongs to the field of spectrum detection and optical imaging. The device comprises a broadband adjustable wavelength light source, a high-resolution wavelength scanning module, a stimulated Raman signal excitation module and a stimulated Raman signal detection module. The stimulated Raman signal excitation and imaging module is used for focusing the two beams of narrow-band femtosecond pulse light which are overlapped in time and space on a sample and exciting a stimulated Raman signal, and meanwhile, moving the sample to realize spot scanning microscopic imaging; and the stimulated Raman signal detection module is used for converting the stimulated Raman scattering signal into an electric signal, demodulating the electric signal by using a lock-in amplifier, and recording spectral information by using a data acquisition card. According to the invention, the broadband tunable characteristic of the optical parametric amplifier is utilized to tune the pump light to the wavelength region of the sample absorption peak length so as to realize electron pre-resonance stimulated Raman; and a balance detection technology is combined at a detection end, so that high-sensitivity, high-resolution and high-signal-to-noise-ratio detection of stimulated Raman signals is realized.

The invention discloses a nanosecond particle velocity measurement method based on orthogonal line polarization beam splitting, and belongs to the technical field of particle image velocity measurement. The method comprises the following steps: providing two linear polarization state orthogonal double-pulse lasers, and respectively outputting S polarization pulse light beams and P polarization pulse light beams; the four pulse light beams are combined through the double-path laser beam combining mirror set and output to the sheet light mirror set, and a plane illumination jet flow field with the thickness smaller than or equal to 1 mm is formed; scattered light is separated according to a polarization state by using a polarization beam-splitting cubic prism, and particle images under S polarization and P polarization are respectively captured by two double-exposure cameras which are orthogonally arranged; five kinds of time sequence control are triggered through a multi-channel synchronous controller; processing the view field deviation of the two cameras by adopting a block polynomial alignment method; and calculating a particle velocity field based on a particle tracking velocity measurement algorithm. According to the invention, the polarization debugging error is reduced, the homogeneity error after beam combination is obviously reduced, the coincidence degree of the four beams of planar light is improved, and a high-precision universal alignment scheme is provided for the multi-camera PTV technology.

The invention discloses a full-polarized light acoustic imaging method and device based on a vector absorption ball. The method comprises the following steps: expressing light absorption characteristics of a sample by establishing a mathematical model of the vector absorption ball; measuring the absorption intensity of the sample absorber under the exciting light in different polarization states through a photoacoustic signal; reconstructing a vector absorption ball of each point of the sample according to the absorption intensity of each point of the sample under different polarized exciting light; five structural parameters are extracted through the vector absorption balls at all points of the sample to reconstruct a structural characteristic diagram of the sample; the full-polarized light acoustic imaging device based on the vector absorption ball comprises a polarized pulse light modulation excitation module, a signal detection module, a two-dimensional scanning module and a signal processing module. The method provided by the invention overcomes the defect that the polarization absorption of the sample cannot be completely expressed by the traditional polarized light acoustic imaging, and realizes the measurement of the full-polarization absorption characteristic and the complete structure expression of the corresponding sample in the same set of light path.

A method is disclosed for use in detecting a pulsed optical beam when the pulsed optical beam is transmitted through a scattering medium, wherein the pulsed optical beam comprises a plurality of optical pulses and the method comprises using a plurality of photodetectors of a photodetector array to detect light which is scattered progressively from the same optical pulse as the optical pulse propagates through a plurality of regions of the scattering medium and which is then received progressively on different photodetectors of the photodetector array. The method may be used in particular, though not exclusively, for non-line-of-sight free-space optical communications. An optical receiver for use in detecting the pulsed optical beam and an associated optical system are also disclosed.

The invention relates to the technical field of engineering structure health monitoring, and discloses a smart cable monitoring system, which comprises a smart cable body module, a central steel wire and a fiber bragg grating smart rib are coupled through a hot cast anchor process, and the smart cable body module is used for sensing cable body strain and converting the cable body strain into an optical signal; the signal acquisition device comprises an optical signal transmitting device and a receiving device, the transmitting device directionally transmits a pulse light source to the fiber bragg grating smart rib, and the receiving device acquires multiple groups of light beams refracted and dispersed by a grating; and the data analysis platform solves the strain of the fiber bragg grating by processing the optical signal. The intelligent cable monitoring system and device aim at solving the problems that in the prior art, manual inspection is limited by labor cost and detection frequency, a single sensor is difficult to achieve multi-dimensional data synchronous collection, data transmission delay is high, and the requirement for real-time safety monitoring of an engineering structure cannot be met.

A distributed acoustic system (DAS) that may include two or more lasers that each transmit a continuous wave (CW) light, a pulser disposed after the two the two or more lasers and optically connected to each of the two or more lasers to receive the CW light from each of the two or more lasers and form a light pulse, and an optical amplifier, wherein the pulser is optically connected to the optical amplifier to receive the light pulse from the pulser as an input. The DAS may further include a splitter optically connected to the optical amplifier to optically split the light pulse into two or more light pulses for each output of the splitter a circulator optically connected to each output of the splitter, and a sensor fiber attached to each of the circulators as an output for each circulator.

Room and / or area disinfection apparatuses are provided which generate pulses of germicidal light at a frequency greater than 3 Hz and project the pulses of light exterior to the disinfection apparatuses. In some cases, the apparatus includes processor executable program instructions for receiving data regarding characteristics of a space in which the disinfection apparatus is to be operated. In addition or alternatively, the apparatus may include a remote user interface to affect operation of the disinfection apparatus. In other cases, the apparatus may additionally or alternatively include a means for automatically moving the disinfection apparatus. In yet other additional or alternative cases, the disinfection apparatus may be void of an opaque component 360° around an elongated portion of the germicidal pulsed light source such that light emitted from the germicidal pulsed light source encircles the disinfection apparatus.

The invention discloses a high-resolution local brain blood oxygen change measuring method based on self-detection-mutual detection combination, which comprises the following steps: placing two optical fiber probes of an optical fiber brain blood oxygen detection system on the brain scalp, and dividing two self-detection channels and one mutual detection channel according to different light diffusion paths; calculating a time-dependent average partial path length; a laser diode is driven to emit near-infrared pulse light, and two groups of time-resolved reflectivity signals of the three channels are obtained; performing curve optimization on the time-resolved reflectivity signals of the channels 1, 2 and 3 measured twice, and solving an absorption change equation set; solving absorption change values of the linear equations of the channels 1, 2 and 3; obtaining a relational expression between the change of the absorption coefficient of the local areas with different wavelengths and the blood oxygen concentration; and solving the relational expression group of the same wavelength and the local region to obtain the blood oxygen concentration change of the local region. The method has the advantage of improving the spatial resolution of the time domain fNIRS and the signal-to-noise ratio of the time gate signal of the time resolution reflectivity.

The present invention relates to the technical field of optical fiber sensing, and particularly relates to an optical time-domain reflectometer, and a method for eliminating interference fading. The optical time-domain reflectometer comprises: a laser device, a frequency-division multiplexing modulator, a circulator and a signal processing apparatus, wherein the frequency-division multiplexing modulator comprises a first modulator, a second modulator, a first attenuator and a second attenuator; the laser device is used for generating a coherent light source, and the coherent light source sequentially passes through the first modulator and the first attenuator, so as to obtain a first pulsed light signal; the coherent light source sequentially passes through the first modulator and the second modulator, so as to obtain a second pulsed light signal; and the coherent light source sequentially passes through the second attenuator and the second modulator, so as to obtain a third pulsed light signal. Therefore, by means of different combinations of the first modulator, the second modulator, the first attenuator and the second attenuator, multiple pulsed light signals can be outputted; and compared with the prior art, hardware costs are saved.

The invention provides a device for generating multiple beams of time sequence light based on a single-circle light spring, and relates to the technical field of ultrafast imaging, and the device comprises a leading edge tilt pulse generation system which is used for generating a long elliptical leading edge tilt pulse; the light spring generation system comprises a polarizer, a first wave plate, a diaphragm, a geometric conversion device, a convex lens, a phase compensator and a second wave plate which are sequentially arranged along the pulse propagation direction, and generates a single circle of light spring pulse based on the long elliptical leading edge tilt pulse output by the leading edge tilt pulse generation system; and the time sequence light beam generation system is used for dividing the single-circle light spring pulse into a plurality of beams of time sequence light through a circular porous diaphragm and a lens group. According to the invention, multiple beams of time sequence pulses can be generated as a coherent shutter to interfere with a signal light beam carrying ultrafast event information, multiple beams of time sequence light can be efficiently generated, multi-beam interference noise is optimized, and efficient image separation of ultrafast imaging is realized.

The invention discloses an equivalent self-noise pressure suppression method based on a dual-channel distributed acoustic sensing system, and the method comprises the steps: carrying out the light splitting of light emitted by a narrow-linewidth laser through a first coupler C1, enabling one path of light to generate a pulse signal through an acoustic optical modulator (AOM), enabling the other path of light to pass through a second coupler C2, and enabling the other path of light to pass through a second coupler C1; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; according to the invention, based on a dual-channel DAS system, two fiber cores of the multi-core optical fiber are used as sensing optical fibers, and the space division signals of the two cores are multiplexed, so that the performance that the equivalent self-noise pressure drop is 2.54 dB in the frequency band of 100-1000Hz is realized under the condition that the noise correlation coefficient of the dual-core signals is 0.11, and the detection capability of the system on low-frequency weak signals can be improved.

A method of scanning a field of view implemented by a Light Detection and Ranging (LIDAR) system includes transmitting pulsed light into the field of view; receiving, by a photodetector array, light from the field of view, wherein the photodetector array is configured to receive the light from objects in the field of view corresponding to ambient light and the pulsed light reflected therefrom; generating, by the photodetector array, DC signal components exclusively attributed to receiving the ambient light and AC signal components exclusively attributed to receiving the pulsed light; separating, by a processing circuit, the DC signal components from the AC signal components; generating, by the processing circuit, a two-dimensional image that represents an ambient light image of the field of view from the DC signal components; and generating, by the processing circuit, a three-dimensional image of the field of view from the AC signal components.

The invention provides a BOTDR (Brillouin optical time domain reflectometry) system fusing Stokes-anti-Stokes light and a demodulation method, and belongs to the technical field of Brillouin distributed optical fiber sensing. The narrow linewidth laser is used for generating continuous optical signals; the input end of the coupler is connected with the laser, and the output end is connected with the pulse light branch and the local oscillator light branch. The pulsed light branch comprises a semiconductor optical amplifier, a random scrambler, a first erbium-doped optical fiber amplifier and a circulator which are connected in sequence; the local oscillator light branch comprises an electro-optical modulator, and the electro-optical modulator regulates and controls sideband frequency through a microwave module; the second erbium-doped optical fiber amplifier is used for extracting the Stokes light and the anti-Stokes light; the single-mode coupler mixes the double-sideband local oscillator light with the anti-Stokes light and the Stokes light; and the electrical beat frequency signals are acquired, filtered and enveloped and demodulated through an acquisition card. The detection capability of the Brillouin scattering signal is enhanced, the system structure is simplified, and the hardware cost and the maintenance difficulty are reduced.

Disclosed in the present invention is a near-infrared wavelength scanning pulse fiber laser having a low mode-locking threshold. According to the present invention, a nonlinear amplifying loop mirror and a saturable absorber mirror architecture are used to achieve a low mode-locking threshold and ensure long-term mode-locking stability. After mode-locking self-starting, an automatic control module automatically achieves single-pulse operation by adjusting the intensity of retro-reflected pulses. In the single-pulse operation stage, different frequencies of radio frequency signals and different signal intensities are provided for an acousto-optic tunable filter by means of a radio frequency module to achieve a 1030 nm-1100 nm wavelength scanning and tuning range.

The invention provides a distributed optical fiber sound wave sensing chip, system and method based on polarization state detection. The chip comprises an optical pulse source module, a first spot size converter, a second spot size converter and a high-speed polarization analysis module, the optical pulse source module generates pulse light and outputs the pulse light to the optical fiber circulator and the sensing optical fiber through the first spot size converter; the second spot size converter receives scattered light returned from the sensing optical fiber and the optical fiber circulator and inputs the scattered light into the high-speed polarization analysis module; the high-speed polarization analysis module comprises a polarization beam splitting rotator, four interference structures and six photoelectric sensors; the polarization beam splitting rotator divides the scattered light into a TE mode and a TM mode, rotates the TM mode to the corresponding TE mode and then outputs the scattered light through two output ports of the polarization beam splitting rotator; each output end of the polarization beam splitting rotator is connected to one photoelectric sensor and one input end of the four-way interference structure; the four-way interference structure is provided with four output ends which are respectively connected to the rest photoelectric sensors.

The invention provides a pulse laser frequency control device and method, and belongs to the technical field of pulse fiber lasers. Comprising a frequency measurement module used for acquiring the frequency of a first external control signal; the frequency selection and frequency division module generates and outputs a seed frequency signal and a frequency division coefficient according to the frequency of the first external control signal obtained by the frequency measurement module; the frequency generation module is used for receiving the seed frequency signal output by the frequency selection and division module and outputting a seed frequency trigger signal; the pulse generation module is used for acquiring the seed frequency trigger signal output by the frequency generation module and providing a seed pulse signal for the seed driver, and the seed driver outputs pulse light according to the input seed pulse signal; the current control module is used for receiving a second external control signal and providing a current driving signal for each pump driver; and the RAM controller is used for receiving a third external control signal and the frequency division coefficient output by the frequency selection and frequency division module, and controlling the acousto-optic modulator to work.

The invention discloses a method and device for optimizing metal powder laying additive manufacturing, the method comprises the steps that optical fiber beam combination is conducted on short pulse optical fiber laser and continuous optical fiber laser which are the same in wavelength to form a composite light source, and the pulse width of the short pulse optical fiber laser is the nanosecond level or the subnanosecond level; the composite light source is output to the galvanometer module through the beam combining optical fiber and then acts on the metal powder bed, and the low-cost and high-efficiency method of full coaxiality and concentricity of lasers of different light sources through the beam combining optical fiber is adopted, so that the printing stability, reliability and large-area uniformity are guaranteed; the short pulse laser and the continuous laser act on an irradiation metal area synchronously and coaxially all the time in the scanning process, metal powder bed melting manufacturing under the force oscillation effect is achieved, and the stability of a keyhole in the additive manufacturing process is improved. According to the method, the pore forming probability of laser powder laying sintering three-dimensional forming can be greatly reduced, the comprehensive mechanical property of a printed piece is improved, and wide popularization and application prospects are achieved.

An optical path testing device and an optical path testing method divide output light from a laser light source into a probe optical path and a local optical path and convert modulated light obtained by modulating input light of the probe optical path into probe light including pulsed light, generate a beat signal by causing signal light and input light of the local optical path to interfere with each other, acquire a signal indicating backscattered light in the optical fiber on the basis of the beat signal, and analyzes a loss distribution, generate the modulated light by performing, on the output light, modulation based on a frequency changing from a start frequency to an end frequency, generate an analysis signal by averaging the backscattered light in each different frequency band included in the beat signal between the different frequency bands and acquire the loss distribution.

The invention relates to a method for detecting a marine corrosion primary process, which comprises the following steps of: constructing three vacuum chambers and connecting the three vacuum chambers by using vacuum pipelines to form a detection system; ultrafast femtosecond laser with the repetition frequency being 1 kHz, the single pulse energy being 6 mJ, the pulse width being 35 fs and the central wavelength being 800 nm is generated through a pulse amplifier; one beam of 2mJ enters a vacuum chamber pipeline to be transmitted as a pulse light beam for detection in the original process of ocean corrosion, the other beam of 4mJ is transmitted outside the vacuum chamber to be used as a pump pulse light beam, and 400 nm pump pulse laser is generated through frequency doubling of a BBO crystal; the pump light beam and the detection light beam are incident on a sample of a sample mechanism in the third vacuum chamber, then the pump light beam is blocked, and only the detection light beam is incident on the sample; xUV light beams reflected from the sample are subjected to spectral dispersion and then enter a CCD detector, and the dynamic response of the sample after being excited by the pump light is monitored by measuring the transmissivity, reflectivity or absorption change of the surface of the sample.

The invention discloses a femtosecond laser three-dimensional pumping detection imaging method, which belongs to the technical field of ultrafast laser observation, and particularly comprises the following steps of: generating a laser pulse by using an ultrashort pulse laser, splitting the laser pulse by using a beam splitter to generate two beams of pulse light, namely pumping light and detection light, ablating a material by using the pumping light as an excitation source, reflection or transmission imaging is realized at different moments after the probe light passes through the time delay table; a detection angle is freely adjusted in space around a sample to be detected by rotating the light path propagation system, and a detection mode is switched between a reflection mode and a detection mode by rotating the imaging system; a multi-angle two-dimensional transient image is fused into a three-dimensional graph, plasma and a double-temperature model are expanded, the electronic dynamic characteristics of three-dimensional space distribution and the plasma eruption process can be calculated in an ultrafast scale, and three-dimensional information of a femtosecond laser ablation material is reduced. The problem that an existing imaging method cannot achieve three-dimensional imaging of the femtosecond laser processing ultrafast process at any angle in the space is solved.

The invention discloses a water quality monitoring device and a monitoring method thereof, belongs to the technical field of water quality monitoring, and solves the problems that trace hydrogen sulfide generated by sulfate reducing bacteria in a deposited layer at the bottom of a water tank which is not cleaned for a long time in a low-oxygen environment reacts with a platinum membrane electrode of a residual chlorine sensor to generate a platinum sulfide covering layer; and the electrode reading is continuously virtually high and drifts slowly. Comprising an optical transmitting module, an optical receiving module, a spectrum separation module, a signal conditioning module, a lock-in amplification module, a spectrum feature extraction module and a hydrogen sulfide recognition engine. Residual chlorine is monitored in a non-contact mode, deep ultraviolet pulse light is emitted to penetrate through a water body, a reflection spectrum is received, second derivative spectral characteristics are extracted through multichannel signal processing, and multivariable regression compensation is executed to calculate a real residual chlorine value after hydrogen sulfide interference characteristics are recognized. Meanwhile, the drift trend is quantified based on the double-time-constant integral, graded early warning is triggered, industrial standard signals are finally output, and the problem of electrode contact pollution is avoided in the whole process.

A bi-directional optical communication system employing a minimum number of single-mode high repetition rate pulsed optical signal sources to achieve cost efficiency while maintaining high data rates. The bi-directional optical communication system includes a first optical data processing unit and a second optical data processing unit. The first optical data processing unit modulates a pulsed optical source using a differential quadrature phase shift keying (DQPSK) modulation and two-level pulse amplitude (PAM-2) modulation and then demodulates it to achieve a pulse amplitude modulated signal. The second optical data processing unit reuses the same optical carrier by passing it through a regenerative wavelength converter to generate three pulsed optical carriers at different wavelengths and employs an On-off keying (OOK) modulation scheme. These carriers are employed to send uplink data at a same rate of as the downlink. As a result, large data is transmitted from one data center to another data center through a downlink and uplink free space optical link network.

In a ranging device, a characteristic setting unit is configured to extract, from one or more pieces of received-light information representing changes with time in amount of received light acquired by the light receiving unit, at least one of a received-light amount range and a light reception time range of pulsed light other than emitted light from the light emitting unit, as a specified range. A received-light integration unit is configured to generate integrated received-light information by integrating the received-light information on a time axis with emission timings matched over a plurality of light receptions. A distance calculation unit is configured to exclude or identify distance noise formed of pulsed waveforms arising from pulsed light other than the emitted light, using the specified range extracted by the characteristic setting unit, and calculate a distance to the object reflecting the emitted light.

An intelligent automatic intense pulsed light therapeutic apparatus relates to the technical field of intense pulsed light therapy and comprises a therapeutic apparatus body, an auxiliary mechanism, an adjusting mechanism and a clamping mechanism, the therapeutic apparatus body is formed by combining a lower shell, a middle frame and an upper shell, a control panel is placed in the middle frame, and the clamping mechanism is arranged on one side of the middle frame. The middle frame is movably connected with a connecting wire harness through a clamping mechanism, the connecting wire harness is connected with external therapeutic equipment, an adjusting mechanism is arranged in the middle frame, and an auxiliary mechanism is arranged on the side, away from the connecting wire harness, of the middle frame; the clamping mechanism of the device adopts a ball and spring linkage design, so that quick insertion and extraction and stable locking with external equipment are realized; the auxiliary mechanism enables the detachable probe to be mounted conveniently and has an automatic dustproof function through structures such as a guide rail and a limiting frame; the adjusting mechanism is driven by an eccentric wheel, the light spot size and the energy density can be accurately adjusted according to the pressing degree, and the problems that traditional equipment is unstable in connection and a probe is inconvenient to replace are effectively solved.