- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - In vivo and online temperature monitoring based on fiber Bragg greatings during tumor treatment with nanosecond pulse electric field
摘要： the clinical practice, a compact, in-vivo and online monitoring scheme is an important requirement. A fiber Bragg grating (FBG) sensing system was used to online monitor the temperature at the surface of / inside the liver tissue of a rabbit under nanosecond pulse electric field (nsPEF). Single point measurement between the electrodes and multi-point measurement surrounding one electrode were both carried out. Experimental results show that, due to equally spaced (Δt=0.5 s) 300 ns-pulses with E=20 kV/cm at a repetition rate of 4 Hz, the temperature rise in the rabbit liver tumor usually does not exceed ΔΤ=6℃ for 300 pulses. Theoretical analysis of Joule heating model fits well with the experimental results. Both direct measurements and theoretical modelling demonstrated that nsPEF could not deliver enough energy to heat the treated tissue significantly, thus a hyperthermic effect on the tissue can be excluded during this kind of treatment with much high electric field strength and extremely short duration.
关键词： Fiber Bragg grating,Nanosecond pulse electric field,In-vivo temperature monitoring
更新于2025-09-16 10:30:52
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Strong fiber Bragg grating sensor based on optoelectrical oscillation for ultra-fast and ultra-stable position-finding and measurement
摘要： This paper proposes a quasi-distribute sensor based on optoelectrical oscillator (OEO) incorporating a uniform strong fiber Bragg grating (FBG). When reflection spectrum of FBG moves to longer wavelength due to external changes, the oscillation will occur and the target position will be mapped into the oscillating frequency. Ultrahigh stability of <14kHz and ultra-short response time of 1.5s are better than many solutions. The sensing threshold can be tuned linearly with the laser operating wavelength with Pearson's r of 0.9989.
关键词： Fiber Bragg grating,Optoelectrical oscillator,Position-finding,Quasi-distributed sensor
更新于2025-09-16 10:30:52
-
High-Speed All-Optical Modulator Based on a Polymer Nanofiber Bragg Grating Printed by Femtosecond Laser
摘要： On-chip optical modulator for high-speed information processing system has been widely investigated by majority of researchers but the connection with the fiber system is a difficulty. The fiber-based optical modulator is a good solution to this problem. Fiber Bragg Grating has good potential to be used as an optical modulator because of its linear temperature response, narrow bandwidth, and compact structure. In this paper, a new fiber-integrated all-optical modulator has been realized based on a polymer nanofiber Bragg grating printed by femtosecond laser. This device exhibits a fast temporal response of 176 ns and a good linear modulation of -45.43 pm/mW. Moreover, its stability has also been studied. This work firstly employs Bragg resonance to realize a fiber-integrated all-optical modulator and paves the way toward realization of multifunctional lab-in-fiber devices.
关键词： polymer fiber,all-optical modulator,fiber Bragg grating,femtosecond laser micromachining,multi-photon polymerization
更新于2025-09-12 10:27:22
-
Encyclopedia of Maritime and Offshore Engineering || Optical Fiber Sensors for Marine Structural Condition Monitoring
摘要： Effective structural condition monitoring, and the action from it, is likely to result in significant economic savings from a better determination of structural integrity and use of the structure itself. It is also essential for the enhanced prediction of structural service lifetimes based on real-time measurement data obtained. Fiber optic-based sensors have shown real promise for structural condition monitoring, due to the attractive features they possess, such as small size, geometric versatility, multiplexing capability, and resistance to corrosive and hazardous environments. As a result, these sensors have been explored widely for monitoring a wide range of structural materials, including composites, concrete, limestones, carbon/aluminum, and metals (Scott et al., 2013; Sun et al., 2012; Nguyen et al., 2014; Kerrouche et al., 2009a), and the key parameters that have been measured include temperature, strain, vibration, relative humidity, pH, and chlorides, and so on.
关键词： Moisture Ingress Sensor,pH Sensor,Fiber Bragg Grating,Optical Fiber Sensors,Vibration Sensors,Marine Structural Condition Monitoring
更新于2025-09-12 10:27:22
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Analysis of Operation of Photonic Integrated Interrogators for Fiber Optic Sensor Networks
摘要： In this work we present and discuss our solutions of photonic integrated interrogators for application in a novel fiber-optic sensing system, dedicated to monitoring condition of a patient exposed to magnetic resonance imaging (MRI) scanning procedure. The monitoring system makes use of multiple fiber Bragg grating (FBG) based sensors, which offer the advantages of high sensitivity and immunity to strong magnetic fields and simultaneously do not affect the results of an MRI scan. Furthermore, the fact that many gratings can be inscribed within a single optical fiber simplifies the architecture of the sensing network.
关键词： fiber Bragg grating,MRI,fiber-optic sensing system,photonic integrated interrogators,monitoring system
更新于2025-09-12 10:27:22
-
1.5?μm spectral band laser power modulation multilayer graphene refractive index
摘要： Multilayer graphene refractive index (RI) modulation over laser power between 0.6 and 14.3 mW at 1500 nm to 1620 nm wavelength band is performed based on a half graphene cladding fiber Bragg grating (FBG), coming from an FBG, which half is cladding etched and coated with graphene, and another half of the FBG is remained. By measuring the wavelength difference between these two parts of the FBG, the temperature cross sensitivity can be removed. With the in-fiber laser power increase, RI of the multilayer graphene exhibits linearly increasing modulation process. The RI modulation can be deduced by the modulation efficiency of Bragg wavelength shift versus power. The modulation efficiency of different wavelength laser is slightly different, which is mainly due to the different interaction area between light field and coating graphene. The maximum modulation efficiency can get 59.3 pm/mW corresponding to 0.0545RIU (refractive index unit)/W RI modulation efficiency and 7.446 × 10?4 RI increment of the multilayer graphene.
关键词： Laser modulation,Refractive index,Graphene,Optical fiber Bragg grating
更新于2025-09-12 10:27:22
-
High-sensitivity hydraulic pressure sensor based on Fabry-Perot interferometer filled with polydimethylsiloxane film
摘要： A high-sensitivity hydraulic pressure sensor is proposed, which consists of a Fabry–Perot interferometer (FPI) filled with a polymer film of polydimethylsiloxane (PDMS). The FPI structure is fabricated by splicing a section of hollow core fiber (HCF) to the end-face of a lead-in single mode fiber (SMF). Then, the PDMS is filled into the HCF which acts as a light reflector and a diaphragm to detect external pressure variation. As a result, the length of the FPI cavity and the thickness of the PDMS are 137.8 μm and 33.8 μm, respectively. Experimental results indicate that the sensor’s wavelength exhibits a linear response to the hydraulic pressure, which function is described as y = ?7.35 × 10?3x + 1536.395. Here, x and y represent the hydraulic pressure and the wavelength, respectively. The pressure sensitivity is up to ?7.35 nm/kPa. Besides, a temperature compensation method based on a fiber Bragg grating is proposed to eliminate the influence of temperature. Experiments show that the scheme can effectively eliminate the influence of temperature and achieve accurate measurement of hydraulic pressure.
关键词： Fabry-Perot interferometer,polydimethylsiloxane,temperature compensation,hydraulic pressure sensor,fiber Bragg grating
更新于2025-09-12 10:27:22
-
All fiber mode-locked thulium-doped fiber laser using a novel femtosecond-laser-inscribed 45°-plane-by-plane-tilted fiber grating
摘要： Using the novel 45°-plane-by-plane-tilted fiber grating inscribed by a femtosecond laser as an in-line fiber polarizer, we demonstrate an all-fiber passively mode-locked thulium-doped fiber laser. We characterize the grating for polarization-dependent loss, indicating high contrast and broad operating wavelength. The 45°-tilted fiber grating together with polarization controller act as an artificial saturable absorber suitable for mode-locking through nonlinear polarization rotation. By properly pre-adjusting the polarization controller, stable mode-locking is achieved for a pump power in the range of 300 mW–400 mW at 1565 nm. Owing to the net anomalous dispersion, a stable mode-locked soliton pulse centered at 1870 nm with a pulse width of 862 fs is reported at a fundamental repetition rate of 22.34 MHz. A long-term stability test reveals that the laser is quite stable for 24 h under laboratory conditions, confirming the capabilities of the 45°-tilted fiber grating for stable laser operation.
关键词： fibre lasers,tilted fiber Bragg grating,dissipative soliton,thulium doped fibre,soliton mode-locking
更新于2025-09-12 10:27:22
-
Optical Fiber-Based Sensing, Measuring, and Implementation Methods for Slope Deformation Monitoring: A Review
摘要： Slope instabilities are a common occurrence in hilly areas, mine, and dam region, which bring a grave threat to the safety of transportation business and human life. The effective slope monitoring methods and instruments can provide information on the current deformation and historical trends, which is important scientific information for researchers to analyze slope stability and provide a timely warning to the public. Optical fiber sensors (OFS) have attracted many researchers to explore due to their have unique advantages in comparison with conventional electronic based sensing technologies, including immunity to electromagnetic interference, remote transmission, easy integration and high sensitivity. This paper presents an overview of the latest development and application of OFS based slope deformation monitoring from two aspects: 1) Fiber Bragg grating (FBG) based sensing and monitoring technology; 2) Distributed optical fiber sensors (DOFS) Brillouin Optical Time Domain Reflectometry (BOTDR) and Brillouin Optical Time Domain Analysis (BOTDA) for slope monitoring. Meanwhile, current challenges in implementing the OFS-based slope monitoring technology are discussed.
关键词： Optical fiber sensors,Distributed optical fiber sensors,Fiber Bragg grating,Slope deformation monitoring
更新于2025-09-11 14:15:04
-
Switchable multi-wavelength thulium-doped fiber laser employing a polarization-maintaining sampled fiber Bragg grating
摘要： A continuous wave, switchable multi-wavelength, thulium-doped fiber laser (TDFL) with a polarization-maintaining sampled fiber Bragg grating (PM-SFBG) is proposed and demonstrated for the first time. A length of 150 m highly-nonlinear fiber (HNLF) was used to introduce the four-wave mixing effect for the efficient suppression of the wavelength competition existing in the gain medium of thulium-doped fiber. By adjusting the state of polarization (SOP) of light in the laser cavity, two six-wavelength operations at two orthogonal SOPs and a ten-wavelength operation were obtained. When the TDFL ran at the six-wavelength operation mode with a pump power of 4.11 W, there were at least four lasing wavelengths with an optical signal-to-noise ratio (OSNR) higher than 30 dB, and when it ran at the ten-wavelength operation mode with a pump power of 4.60 W, there were nine lasing wavelengths with an OSNR higher than 30 dB. Regardless of the operation mode, the TDFL exhibited high stability.
关键词： sampled fiber Bragg grating,thulium-doped fiber laser,multi-wavelength
更新于2025-09-11 14:15:04