Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

1233 results about "Continuous light" patented technology

Full-distributed optical fiber strain and vibration sensor based on coherent heterodyne detection

The invention relates to a full-distributed optical fiber strain and vibration sensor based on coherent heterodyne detection, which comprises a laser (1), a coupler, a pulse modulation module, a programming gain amplifier (4), an optical amplifier, a circulator (6), a sensing fiber (7), a polarization-preserving fiber (8), the coupler, a balancing photoelectric detector (10), a reversal switch, a mixer, a microwave source, a band-pass filter, and a signal processing unit, wherein the continuous light output by the laser (1) is divided into two paths after passing through the coupler (2); an output end of the balancing photoelectric detector is connected to the reversal switch; the reversal switch is switched to a channel 1 and a channel 2; when the channel 1 is switched on, the system utilizes the Brillouin optical fiber time domain reflection to measure; and when the programming gain amplifier (4) is closed and the channel 2 is switched on, the system utilizes the polarization optical time-domain reflection to measure. By using the full-distributed optical fiber strain and vibration sensor provided by the invention, the full-distributed measurement for strain as well as the weak vibration and the full-distributed measurement for vibration can be performed on a single optical fiber.
Owner:NANJING UNIV

Fully distributed optical fiber strain and vibration sensing method and sensor

The invention discloses a fully distributed optical fiber strain and vibration sensor comprising a laser (1), a first coupler (2), a pulse modulation module (3), an optical amplifier (4), a circulator (5), a sensing optical fiber (6), a fiber bragg grating (7), a polarization scrambler, a second coupler, a balance photoelectric detector, an analyzer, a photoelectric detector (12) and a signal processing unit. Continuous light output by the laser (1) is split into two paths through the first coupler (2), wherein one path is used as reference light and is accessed to a first input end of the second coupler (9) through the polarization scrambler (8); and the second path is processed by the pulse modulation module (3) and the optical amplifier (4) and then used as detection pulse light to be injected into a first port of the circulator (5). In the invention, Brillouin optical time domain reflectometry (BOTDR) and polarization optical time domain reflectometry (POTDR) are simultaneously utilized for respectively and correspondingly carrying out fully distributed measurement on strain and vibration on a signal optical fiber, the defects of a system with single BOTDR or POTDR are overcome, and the false alarm rate or missed report rate of the system is decreased.
Owner:NANJING UNIV

Fiber bragg grating array-based phase-sensitive optical time domain reflection device and method

The invention discloses a fiber bragg grating array-based phase-sensitive optical time domain reflection device and method. The device includes a light source, a laser frequency adjustment module, a modulator, an optical fiber amplifier, a circulator, a sensing optical fiber, a light detector, a data acquisition module and a data processing module; the sensing optical fiber is provided with an optical fiber array formed by a plurality of FBGs (fiber bragg grating) which are arranged equidistantly; the laser frequency adjustment module is used for frequency adjustment of continuous light emitted by the light source; the continuous light is modulated by the modulator so as to form pulsed light; the optical fiber amplifier performs power amplification on the pulsed light; the sensing optical fiber is used for receiving and transmitting the pulsed light which has been subjected to power amplification; the light detector receives scattered light and reflected light; the scattered light and reflected light are acquired by the data acquisition module; and the data processing module generates interference signal frequency response spectrum and obtains the length variation quantity of the sensing optical fiber between two adjacent FBGs through processing. With the fiber bragg grating array-based phase-sensitive optical time domain reflection device and method of the invention adopted, strain quantitative detection can be realized, and high-spatial resolution measurement can be realized based on quantitative analysis.
Owner:NANJING UNIV

Optical fiber distributed disturbance sensor

The invention discloses an optical fiber distributed disturbance sensor which comprises an optical fiber laser, a bidirectional distributed Raman amplification unit and a photoelectric detection and signal processing unit, wherein an output end of the optical fiber laser is connected with a first coupler; two output ends of the first coupler are respectively connected with an acoustic optical modulator and a third coupler; the bidirectional distributed Raman amplification unit is connected with the acoustic optical modulator by a first circulator and is connected with the third coupler by the first circulator; the photoelectric detection and signal processing unit is connected with the third coupler and used for receiving an interference-enhanced optical signal in the third coupler, converting the optical signal into an electric signal and carrying out subsequent data processing. In the optical fiber distributed disturbance sensor, the back scattering light intensity and the signal-to-noise ratio of the tail end of the optical fiber can be improved by the bidirectional distributed Raman amplification structure so as to improve the sensing distance of the optical fiber distributed disturbance sensor; and the light power received by a detector can be improved through the interference of a part of continuous light output by a light source and the back scattering light, so as to improve the signal-to-noise ratio of the system. The sensor is a combination of conventional photoelectric devices, has a simple structure and is easy to realize.
Owner:BEIHANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products