2385 results about "Optical fiber coupler" patented technology

The inventive optical fiber coupler array is capable of providing a low loss, high-coupling coefficient interface with high accuracy and easy alignment between a plurality of optical fibers (or other optical devices) with a first channel-to-channel spacing, and an optical device having a plurality of closely-spaced waveguide interfaces with a second channel-to-channel spacing, where each end of the optical fiber coupler array is configurable to have different channel-to-channel spacing, each matched to a corresponding one of the first and second channel-to-channel spacing. The novel optical coupler array includes a plurality of waveguides (at least one of which may optionally be polarization maintaining), that comprises at least one gradually reduced vanishing core fiber, at least in part embedded within a common housing structure. Alternatively, the novel coupler array may be configured for utilization with at least one of an optical fiber amplifier and an optical fiber laser.

The invention discloses a distributed optical fiber sensing device based on a chaotic laser coherence method, and a measurement method of the distributed optical fiber sensing device. Chaotic laser light which is emitted from a chaotic laser is divided into detection light and reference light; the detection light is amplified by a light amplifier and then emitted into a sending optical fiber through an optical circulator, and a backward Brillouin scattering light signal is generated in the optical fiber; the Brillouin scattering light signal is amplified by the light amplifier, de-noised by a tunable light filter and then emitted into an optical fiber coupler; the optical length of the reference light is regulated by a variable light delay line, and interferes with the backward Brillouin scattering light signal which is generated by the detection light at different positions in the sensing optical fiber in the optical fiber coupler; an interference beat frequency signal is detected by a photoelectrical detector; and Brillouin gain spectra at different lengths are obtained through a data acquisition device and a signal processing device and then output to a display device, so strain or temperature sensing detection is realized.

A media converter to converts digital fiber optic signals to electronic analog signals in the form of voltage doublet and vice-versa. The media converter includes a differential transmit transformer, a transmit stub interface and an optical fiber transmit interface arranged in serial flow communication in a first communication path; and a differential receive transformer, a receive stub interface and an optical fiber receive interface in serial flow communication in a second communication path. The first communication path converts a voltage doublet signal received from the electronic component to a digital optical signal for transmission to a passive optical star via the optical fiber coupler, and the second communication path converts a digital optical signal received from the passive optical star via the optical fiber coupler to an voltage doublet signal for transmission to the electronic component.

The invention discloses an optical frequency division multiplexing phase-sensitive optical time domain reflectometer which comprises a narrow line width laser, an optical fiber coupler, a phase modulator, a scrambler, an erbium-doped optical fiber amplifier, an acoustic optical modulator, an optical fiber circulator, a signal generator module, a trigger source, a double balance detector, a low pass filter, a data acquisition card, a computer and a long-distance sensing optical fiber. According to the optical frequency division multiplexing phase-sensitive optical time domain reflectometer, the fundamental contradictions between the measuring distance and sampling rate in a distributed sensing system can be solved, and remoter or higher-frequency vibration is detected; and moreover, due to amplitude and phase information, the characteristics of a vibration source are judged at the first time, and the early warning can be provided immediately.

The invention discloses an all-optical true random number generator, which comprises an all-optical true random number entropy source, wherein the all-optical true random number entropy source injects output light of a continuous laser device I into a two-section semiconductor laser device through a 3dB optical fiber coupler I and a light attenuator, produces a high-speed chaos self-pulse signal and controls the repeated frequency of the chaos self-pulse signal by adjusting the light injection intensity and the frequency detuning amount. Sampling and subsequent processing are not required; the additional problem caused by signal distortion because of sampling in the prior art is solved; the complexity of a system is greatly reduced; a code rate can be tuned in a large range by changing the light injection intensity and the frequency detuning amount; and the code rate is up to Gbps and can be directly compatible with a light network.

The invention relates to a full optical fiber instant passing wave biology sensor technology to realize biological detection by using laser to excite the biology material to emitting. The feature is that the laser transferring and fluorescence receiving path of the sensor contains an optical fiber probe, a single and multiple optical fiber coupler. The laser from the laser emitting device would send to the end of the single-mode optical fiber, and the other end coupling to multimode fiber. One end of the multimode fiber connects to fiber probe, and the other end locating in the light incidence end of fluorescence collecting and data processing device. The invention could decrease the consumption, improve coupling efficiency and decrease optical discrete element and simplify instrument structure.

The invention discloses an online health monitoring system and method for a composite material. The system comprises an optical fiber grating demodulator, an optical fiber coupler, a processor and a double-lead array optical fiber grating pair sensor. A light source emits light signals, and the light signals are divided into two ways through optical fibers, and connected to the two ends of the double-lead array optical fiber grating pair sensor through one optical fiber coupler. All optical fiber gratings are embedded into the composite material. After the light signals and the optical fiber gratings are mutually affected, reflected light enters the optical fiber grating demodulator through the optical fiber coupler. The optical fiber grating demodulator is connected with the processor. The processor calls a damage database of the composite material, analyzes the damage type, degree and distribution of the fiber composite material to set up a three-dimensional model, outputs the damage distribution of the composite material, calculates residual intensity of the composite material by means of finite element analysis, and evaluates the health condition of the composite material. The system monitors the damage state of the composite material and gives out early-warning in real time.

The invention relates to a distributed optical fiber sensing system, and in particular relates to a chaos Brillouin optical coherence domain analysis distributed optical fiber sensing device and method. According to the invention, the problems of unavailable spatial resolution and sensing distance combination, severely limited sensing distance and low spatial resolution of the existing distributed optical fiber sensing system are solved. The chaos Brillouin optical coherence domain analysis distributed optical fiber sensing device comprises a wide spectrum chaos semiconductor laser, a 1*2 optical fiber coupler, an optical scrambler, an optical isolator, a first optical amplifier, a variable optical delay line, a second optical amplifier, an optical circulator, a sensing optical fiber, a tunable optical filter, a broadband gain photodetector, a data acquisition device, a signal processing device and a display device. The device and the method, which are provided by the invention, are applicable to the field of distributed optical fiber sensing.

The invention discloses an intelligent monitoring device for blades of a wind driven generator, which comprises a blade body, a power generator, a plurality of fiber bragg grating sensors and a fiber bragg grating signal analyzer. The blade body is mounted on a hub, the power generator is connected with the hub through a gear box and a spindle or is directly connected with the hub, the fiber bragg grating sensors are arranged on the blade body, and the fiber bragg grating signal analyzer is connected with the fiber bragg grating sensors through optical fibers and an optical fiber coupler. Besides, wavelengths of different fiber bragg grating sensors on the blade body are different, the fiber bragg grating signal analyzer measures amplitude and frequency relations of corresponding temperature, vibration and dependent variables of optical signals of different wavelengths to acquire information about vibration, dynamic balance, fatigue, deformation, load and damage of the blade body, thereby assisting working staff to handle accidents in time.

The invention discloses an ultra-high-precision freezing detecting device and a real-time freezing thickness detecting method thereof. The ultra-high-precision freezing detecting device comprises a wideband light source, a spectrum analyzer, an optical fiber coupler, a film-coated optical fiber, an optical fiber polarization controller, an optical switch and optical fiber probes. The wideband light source and the spectrum analyzer are connected to a port a and a port b which are located on the same side of the optical fiber coupler through optical fibers respectively. The film-coated optical fiber is installed on the optical fiber polarization controller and connected to a port c located on the other side of the optical fiber coupler. The input end of the optical switch is connected to a port d of the optical fiber coupler and the output end of the optical switch is connected with the optical fiber probes. The ultra-high-precision freezing detecting device can realize ultra-high-precision detection of a micrometer-level-thickness ice layer on the surface of an object and accurately forecast the freezing rate. In addition, the device is high in integration degree, low in cost, capable of realizing distributed real-time detection, particularly suitable for airplane freezing detection, capable of realizing safety early warning and capable of being widely applied to other fields in need of freezing condition detection or monitoring.

A coupler to interconnect or couple optical fibers together and position ends of the optical fibers juxtaposed with each other, additionally includes a captive split tubular alignment sleeve to accept ferrules on ends of optical fibers to be aligned and coupled. The coupler may be incorporated into an opto-electronic module, captured, and then held against normal forces of connecting and disconnecting the optical fiber. A short optical fiber extends from the coupler through a wall of an enclosure and is terminated adjacent an opto-electronic device to carry optical signals for transmission or reception of optical signals. This coupler may be further used to splice or interconnect optical fibers, in temporary connections or splices, without fusing the glass of the fibers.

The inventive optical component assembly advantageously enables a multi-waveguide optical component (such as the inventive optical fiber coupler array, a multi-core optical fiber, etc.), to be coupled to at least one waveguide of an optical device at a predefined coupling angle. The optical component assembly of the present invention comprises a multi-waveguide optical component with an output end, a prism having an input surface, an output surface, and an internal reflective surface with a predefined reflection angle, and a GRIN lens, positioned between the component output end and the prism input surface, along a longitudinal axis of the multi-waveguide optical component. In accordance with the present invention, the length of the GRIN lens, and its refractive index gradient profile are optimized to form an optical image of the output end of the multi-waveguide optical component, at the output surface of the prism, thus enabling the output surface of the prism to be coupled to at least one waveguide of an optical device, with the predefined reflection angle corresponding to the angle at which the multi-waveguide optical component may be coupled to the optical device.

The invention discloses a wavelength-encoding optical time domain reflection test device and a measurement method thereof. The device comprises an optical wavelength encoding generator, an optical fiber splitting device, a polarization controller, an optical fiber coupler, a photoelectric detector and a beat frequency signal detection device; wherein an encoding optical pulse signal generated from the optical wavelength encoding generator is input from a first port of the optical fiber splitting device and divided into a detection light signal and a reference light signal which are respectively output from a second port and a third port of the optical fiber splitting device; the detection light source enters into an optical fiber link to be tested, and a reflected light signal generated after meeting breakpoints or damages of the optical fiber link to be tested returns to the optical fiber splitting device from the second port and is output from a fourth port; the reflected light signal passes through the polarization controller, then passes through the optical fiber coupler together with the reference light signal and enters into the photoelectric detector to carry out frequency beating, and a beat-frequency low-frequency signal enters into the beat-frequency signal detection device and is then observed and recorded. The invention solves the problems that the OTDR resolution ratio and the dynamic range of the traditional device can not be simultaneously improved.

The invention discloses a sensing signal detecting device and a sensing signal detecting method based on a fiber Brillouin ring laser. The device comprises a narrow linewidth DFB (distributed feedback) laser, three optical fiber couplers, a pulse modulator, two erbium-doped fiber amplifiers, two optical fiber circulators, two single-mode fibers, an optical isolator, a polarization controller and a photoelectric detector, wherein the fiber Brillouin ring laser is composed of the second optical fiber circulator, the second single mode fiber, the optical isolator, the second optical fiber coupler and the polarization controller. Light emitted from the laser is divided into two beams of light via the optical fiber couplers, wherein the probe light is modulated into pulsed light which enters into sensing optical fiber after passing through the erbium-doped fiber amplifiers to ensure that back spontaneous Brillouin scattered signals are generated; the reference light passes through the center frequency of the fiber Brillouin ring laser to ensure that a Brillouin frequency shift is generated; and the coherent detection is carried out on the two Brillouin scattered signals which are scattered back to ensure that the advantages of rapid high-accuracy detection and simple structure are realized by utilizing low-cost devices.

The invention provides a simplified multiplexing white light interference fiber sensing demodulating device, which comprises a single-fiber two-way optical transmitting/receiving module, an optical fiber resonant cavity, a single-mode transmission fiber, and an optical fiber sensing array, wherein the single-fiber two-way optical transmitting/receiving module is composed of a semiconductor light source as the transmitting terminal, a semiconductor photodetector as the receiving terminal and related devices packaged together; and an optical fiber annular cavity is composed of an optical fiber coupler, an optical fiber self-focusing lens and a movable corner reflector. The device can achieve enquiry and measurement of a plurality of optical fiber sensors by embedding the single-fiber two-way optical transmitting/receiving module and the optical fiber resonant cavity in the single-mode optical fiber, and has the advantages of simple structure, easy implementation, no length restriction of the transmission cable, no influence caused by the external environment, and good stability and reliability. The device can be used for the measurement of physical quantities such as distributed deformation, strain and temperature, and can be used for multi-task sensing, multi-element sensing, local strain sensing, large-scale deformation sensing, etc.

A method for generating a broadband chaotic signal similar to white noise comprises the steps that beat frequency is carried out on two paths of chaotic lasers through an optical fiber coupler, the two paths of chaotic lasers are divided into two paths with the equal intensity, balanced detection is carried out on the two paths of optical signals, and a difference value signal is extracted and converted into a corresponding electric signal. A device for generating the broadband chaotic signal similar to the white noise comprises two chaotic laser emission devices, the optical fiber coupler and a balance detector. The optical frequencies of the chaotic laser emission devices are not equal, and an optical frequency difference is the spectral line width of the chaotic lasers. The chaotic signal generated through the method has the wide and flat frequency spectrum similar to that of the white noise, no rectilinear oscillation exists on the frequency spectrum, and periodicity caused when the chaotic lasers are generated through a time delay system can be thoroughly eliminated; the security of chaotic communication, the measurement accuracy of a radar and an optical time domain reflector, and the randomness of physical random numbers are improved. The method and device can be applied to the fields of communication, remote sensing, sensing and the like.

A tunable-frequency photoelectric oscillation device based on a wide spectrum light source comprises the wide spectrum light source, an optical filter, a first light amplifier, a second light amplifier, a first optical fiber coupler, a second optical fiber coupler, a third optical fiber coupler, a first polarization controller, a second polarization controller, a dimming-adjustable delay line, an photoelectric modulator, a color-dispersion optical fiber, a first photoelectric detector, a second photoelectric detector, a microwave amplifier, a first optical fiber patch cord, a second optical fiber patch cord, a third optical fiber patch cord, a fourth optical fiber patch cord, a fifth optical fiber patch cord, a sixth optical fiber patch cord, a seventh optical fiber patch cord, a first cable and a second cable. The tunable-frequency photoelectric oscillation device based on the wide spectrum light source can generate wideband-adjustable microwave signals, adopts a microwave photon filter to replace a traditional point filter, overcomes the defect that a traditional photoelectric oscillator based on wide spectrum source cutting can not generate signals at certain frequency points, and has the advantages of being low in cost, adjustable in wideband, and low in phase noise.

The invention provides a two-degree-of-freedom heterodyne grating interferometer displacement measurement system and method. The system comprises a double-frequency laser device, a grating interferometer, a measuring grating, a receiver and a signal processing unit. The grating interferometer comprises a lateral displacement light splitting prism, a polarization light splitting prism, a 1/4 wave plate, a reflecting mirror and an optical fiber coupler. The method realizes displacement measurement based on grating diffraction, the optical Doppler effect and the optical-beat frequency principle. Laser of the double-frequency laser device is incident to the interferometer and the measuring grating and then optical signals are outputted to the signal processing unit. When the interferometer and the measuring grating perform two-degree-of-freedom linear relative movement, the system can output two linear displacements; the measurement system adopts Littrow incident conditions, a measurement target has large passive movement tolerance and two linear displacements can be measured simultaneously so that precision can reach the nanoscale and higher scale; and the measurement system has advantages of short light path, small size, compact structure, low weight and low requirement for the measuring grating and is suitable for two-degree-of-freedom high-precision long-stroke displacement measurement.

The invention discloses a spectrum programmable light source system applied to hyper-spectrum calibration. The spectrum programmable light source system applied to hyper-spectrum calibration comprises a light source. An optical filter, a collimation system, a cylindrical lens coupled system, a slit, a collimation objective and a dispersion element are sequentially placed on a light path in front of the light source, an imaging system and a digital micromirror device are sequentially arranged on a light path in front of the dispersion element, a light collection lens and an optical fiber coupler are arranged on a light path of useful light modulated by the digital micromirror device, wherein the optical fiber coupler is connected with a integrating sphere, a light splitting radiometer is arranged on the integrating sphere, and feedback control is conducted and target spectrums are simulated through a spectrum simulation program and monitoring the light splitting radiometer. A focusing system and a garbage light collector are sequentially arranged on a light path of garbage light modulated by the digital micromirror device, and the garbage light is eliminated. The spectrum programmable light source system applied to hyper-spectrum calibration can simulate accurately the target spectrums and reduce the effect of inconsistence of calibration light source spectrums and the target spectrums to a calibration result. The spectrum programmable light source system applied to hyper-spectrum calibration accurately measures radiation quantity, and is favorable to improving optical radiation calibration accuracy of a sensor.

The invention relates to a multi-optical axis consistency tester based on a multispectral target plate and a rotating reflector and belongs to the opto-electrical field. The invention comprises the main lens of a large caliber offaxis double reverse collimation mirror, the secondary mirror of the collimation mirror, a double-axis rotating mechanism, a plane mirror, an attenuator, a spectroscope A, a multispectral target plate, a spectroscope B, a near infrared CCD, an optical fiber coupler, an optical fiber, a multi-channel video collecting device, etc. The plane mirror is driven by the rotating mechanism; the multispectral target plate is arranged in the reflection optical path of the spectroscope A; after the transmission optical path of the spectroscope A passes through the spectroscope B, the transmission light enters the near infrared CCD; simultaneously the reflection light enters the incident end of the optical fiber; the other end of the optical fiber is connected with the transmitting end of the laser range measuring machine of the optical fiber coupler; a laser pulse is coupled with and enters the optical fiber. The multi-optical axis consistency instrument device is used for detecting the static and dynamic errors of the consistency between the multi-optical axes in the broad spectrum range of a complex opto-electrical system, has high precision and is conveniently carried.

The invention discloses a multi-channel optical-fiber laser coherence beam combination device and a coherence beam combination method based on overlapped body grating. The device comprises an optical-fiber coupler, a doping double-clad optical-fiber, a lens, a dichroiscope, a reflector, a polarization controller, a reflector, an overlapped body grating and an output coupling mirror connected in sequence at one side of the optical-fiber grating. The method is able to realize the multi-channel optical-fiber laser coherence beam combination without complex phase detection and control to each beam. The phases of each beam realize interlocking by sharing a resonator composed of the output coupling mirror and the optical-fiber grating. Each beam realizes the coherent superposition in the near-field and far-field to significantly enhance the output power and the brightness of the optical-fiber laser through the overlapped body of grating. The invention features the simple structure and complex structure without increasing as the increase of the beam combination laser, and is able to be widely applied in the field needing the large power optical-fiber laser as the light source, thereby capable of gaining the large power, high beam quality as well as compact high-energy laser system.