共查询到20条相似文献,搜索用时 46 毫秒
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利用相位掩模法,在D形内包层掺Yb3+双包层光纤一端直接写制出Bragg光栅,用作双包层光纤激光器的输出腔镜.试验得到了线宽为0.196nm,波长为1058.2nm,最高输出功率为570mW的稳定激光输出,解决了激光器中模式竞争造成的输出不稳定现象.从速率方程出发,对激光器的输出功率与抽运功率、光栅反射率的关系以及最佳光纤长度进行了理论分析,结果与实验符合很好.
关键词:
双包层光纤光栅
掺Yb3+双包层光纤激光器
相位掩模
速率方程 相似文献
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用紫外光直接在光纤内写入布拉格反射光栅的实验研究 总被引:2,自引:0,他引:2
用紫外光直接在光纤内写入布拉格反射光栅的实验研究杜卫冲谭华耀*刘颂豪华南师范大学,激光生命科学研究所,广州510631*香港理工大学,电机系自1989年Meltaz[1]首次提出采用两束波长位于掺Ge-石英光纤吸收带内的相干紫外激光相干涉,从侧面照射... 相似文献
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双波长啁啾相移光纤光栅 总被引:2,自引:2,他引:0
理论研究并实验验证了一种含有两段π相移的啁啾相移光纤光栅.采用F矩阵对啁啾相移光纤光栅进行计算并分析了该光栅的谱特性.含有两段π相移的啁啾相移光纤光栅可以在普通啁啾光栅透射谱阻带中产生双波长透射峰,透射峰位置直接取决于光栅中π相移的位置,透射峰的线宽和透射峰的波长间隔没有关系,仅随着啁啾率的增大而增大.采用带相位掩模的逐点扫描法对含有两段π相移的双波长啁啾相移光栅进行了制作,获得波长间隔为8 nm的双波长透射谱的光栅器件.该光栅的消光比和3 dB谱线宽分别为20 dB和0.08 nm,实验结果和理论设计一致. 相似文献
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Gong Yandong Li Tangjun Cai Qing Li Qin Wang Zhi Guan Yali Zhang Jinsong Jian Shuisheng 《Optics & Laser Technology》2000,32(1)
We used the Modified Chemical Vapor Deposition (MCVD) method to fabricate a B/Ge codoped fiber with a depressed cladding in which boron and germanium were also doped, the depressed cladding was photosensitive, which can greatly suppress the cladding mode coupling. The transmission spectrum of written grating in this fiber made by the phase mask method verified its larger photosensitivity and great suppression of the cladding mode coupling. We then analyzed the Bragg wavelength tuning theory in the phase mask method in detail which gave us a more exact equation. The ultra-violet (UV) exposure system was modified, and eight cascaded Fiber Bragg Gratings (FBG) centered at different wavelengths were written in this photosensitive fiber successfully using a 248 nm KrF excimer laser and one piece of 1067 nm phase mask. Each channel spacing was 100 GH according to the Densed Wavelength Division Multiplexing (DWDM) standards of the International Telecommunication Union (ITU-T). At the same time, we also wrote in chirp in each grating by tilting the phase mask to realize dispersion compensation. The dispersion in 44 km SMF was successfully compensated by the cascaded chirped gratings in the eight channel WDM system with each channel being 10 Gbit/s. 相似文献
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We propose a switchable multi-wavelength erbium-doped fiber laser based on a four-mode fiber Bragg grating(FBG). The four-mode FBG is fabricated in a hydrogen pre-loaded fiber by the phase mask method, which can support four linearly polarized modes around 1550 nm. The five operation wavelengths are at 1547.5, 1546.8,1546.0, 1545.1, and 1544.2 nm, respectively. Through adjusting the polarization state and the lateral offset coupling in cavity, the laser can be switched into the operation state of single, dual, or triple wavelengths. The proposed laser has the advantages of simple configuration, stable operation, and easy adjustment. 相似文献
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A simplified ring cavity for achieving a unidirectional room temperature multi-wavelength erbium-doped fiber ring laser without optical isolator is demonstrated. The fiber ring cavity is built in such a way that the optical fields propagating in two directions suffer different losses caused by one sampled fiber Bragg grating. Furthermore, simultaneous multi-wavelength lasing with 0.8-nm intervals is demonstrated with sinusoidal phase modulation just before the sampled fiber Bragg grating to prevent single-wavelength lasing and unstable wavelength oscillation. 相似文献
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多波长啁啾叠栅的矩阵分析 总被引:1,自引:0,他引:1
在分析多波长啁啾叠栅特征的基础上,提出了多波长啁啾叠栅的矩阵分析模型,采用矩阵分析模型对4波长和8波长啁啾叠栅的反射谱特性进行了理论分析,数值分析结果与实验结果非常一致.还首次数值模拟了波长间隔0.8 nm的16波长啁啾叠栅.此方法对多波长啁啾叠栅的设计和制作具有参考价值. 相似文献
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We propose and experimentally demonstrate a novel fiber-optic edge filter based on modulating the chirp rate of a π-phase-shifted fiber Bragg grating (FBG) operating in transmission mode. The phase shift induced passband in the transmission spectrum is utilized as the edge filter. The dependence of the π-phase-shifted FBG’s transmitted spectral response on the chirp rate has been numerically studied in detail and experimentally confirmed, to the best of our knowledge, for the first time. The linear wavelength range of the proposed edge filter can be tuned by changing the chirp rate of FBG. The edge filter is further tested as a wavelength interrogator, and the experimental results are in good agreement with numerical results. The proposed fiber-optic edge filter has several unique advantages which include simple structure, cost effectiveness, high sensitivity, flexible tunability, and optical circulator is not required, and thus has interesting potential applications, especially as a wavelength interrogator in FBG foot sensors, FBG ultrasound and vibration sensors, and FBG distributed sensors, where the required wavelength ranges are very small (<0.4 nm). 相似文献
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为了解决传统光纤光栅测温系统中单根光纤上带光纤光栅探头数量少、回波光强弱以及复用能力差的问题,设计研究了基于啁啾光纤光栅的测温系统。通过啁啾调制技术提高了回波光的带宽,从而增强了信号的可处理性并大大提高了带探测点位的数量。推导了啁啾调制的光栅周期表达式,给出了调制方法及波长范围。实验采用LPT-102型宽带光源与F-P光纤解调仪等,调制带宽为1 535.0~1 555.0 nm,并结合WR-201型温度传感器作标定。对20~60 ℃范围内每1 ℃改变进行测试,实验结果显示,传统光纤光栅探头与啁啾光纤光栅探头的测试温度误差相近,都符合设计要求。相比而言,啁啾FBG的测试数据对应的波长偏移具有较为明显的单调线性的特征,即数据稳定性更高,同时,采用啁啾FBG的系统带光纤光栅探头数量明显优于传统光纤光栅测温系统。由此可知,本系统在不增加光纤个数及不降低温度测试精度的基础上,实现了大幅提高带探测点位数量的设计要求。 相似文献
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Zhao Chun-Liu Yang Xiufeng Lu Chao Ng Jun Hong Guo Xin Partha Roy Chaudhuri Dong Xinyong 《Optics Communications》2004,230(4-6):313-317
A novel and simple Erbium-doped fiber laser by using cascaded fiber Bragg gratings (FBGs) written in high-birefringence fibers for switchable multi-wavelength operation is proposed. Due to two-peak reflection with orthogonal polarizations of the FBG, the polarization hole-burning effect in the cavity is greatly enhanced. Experimental results show that the stable dual- and three-wavelength lasing operation with very narrow wavelength separation (0.39 nm) can be generated at room temperature. The configuration is simple and flexible. Only by adjusting polarization controllers (PCs), the laser can be switched among the stable single-, dual- and three-wavelength lasing operations. 相似文献
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A new and efficient technique for fabrication of bandwidth controllable π–phase-shifted fiber Bragg grating (FBG) based on moiré grating using a uniform phase mask is demonstrated. The feasibility of writing a moiré grating into an ordinary SMF-28 fiber using stretching and double exposure by ultraviolet fringe is reported. We analyzed the relation between the initial differentia of phase of two exposures and the transmission spectrum of phase-shifted FBG. Moreover, we present a novel method to control the initial differentia of phase of two exposures. Using this technique, two kinds of resonant filters with a 3-dB line-width of 0.01 nm centered at 1553.79 nm and of 0.5 nm centered at 1554.57 nm respectively were fabricated with same uniform phase mask. 相似文献
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A new and efficient technique for fabrication of bandwidth controllable π–phase-shifted fiber Bragg grating (FBG) based on moiré grating using a uniform phase mask is demonstrated. The feasibility of writing a moiré grating into an ordinary SMF-28 fiber using stretching and double exposure by ultraviolet fringe is reported. We analyzed the relation between the initial differentia of phase of two exposures and the transmission spectrum of phase-shifted FBG. Moreover, we present a novel method to control the initial differentia of phase of two exposures. Using this technique, two kinds of resonant filters with a 3-dB line-width of 0.01 nm centered at 1553.79 nm and of 0.5 nm centered at 1554.57 nm respectively were fabricated with same uniform phase mask. 相似文献
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Jianliang Yang Yunqi Liu Sweechuan Tjin Jianping Yao 《International Journal of Infrared and Millimeter Waves》2002,23(8):1241-1250
A photonics true-time-delay system for phased array antenna beam steering employing a novel tunable chirped fiber grating delay line and a multi-wavelength erbium-doped fiber ring laser source based on a sampled grating filter is proposed. The tunable chirped fiber grating, which act as a continuous time-delay element, is achieved by bending a uniform fiber Bragg grating bonded at a slant onto the lateral surface of a simply supported beam. This technique allows the dynamic control of the chirp rate and spectral width of the grating without center wavelength shift. By adjusting the chirp rate of the fiber grating via bend strain, this kind of tunable chirped fiber grating could achieve very low and adjustable delay times, therefore provides higher angle resolution for scanning microwave beam, even the wavelengths of laser source are fixed and un-tunable. The true-time-delay system using proposed tunable chirped fiber grating delay element and sampled grating based laser source is constructed and demonstrated experimentally. 相似文献
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Double-clad Tm3+-doped silica fiber laser with Bragg grating inscribed directly into active core by femtosecond laser 总被引:1,自引:0,他引:1
C. W. Song Y. J. Zhang B. Q. Yao Y. Wang W. Wang Y. L. Ju Y. Z. Wang 《Laser Physics》2009,19(5):1009-1012
We report for the first time to inscribe the Fiber Bragg Grating (FBG) in Tm3+-doped multimode double-clad silica fiber by 800 nm femtosecond laser with a phase mask. The 1.35 μm period Bragg grating is written into the fiber core, which is responded to the laser center wavelength located at nearly 1960 nm. Continuous wave total output power of 11.5 W is obtained under the launched pump power of 29.8 W, corresponding to a slope efficiency of 45.0% and a conversion efficiency of 38.6%. 相似文献
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Highly reliable strain-tuning of an Erbium-doped fiber laser for the interrogation of multiplexed Bragg grating sensors 总被引:1,自引:0,他引:1
Aleksander S. Paterno Nilton Haramoni Jean C.C. Silva Hypolito J. Kalinowski 《Optics Communications》2007,273(1):187-192
The authors implemented a tunable linear cavity Erbium-doped fiber (EDF) laser for the interrogation of multiplexed fiber Bragg grating sensors (BGS). A high-strength single-pulse draw-tower fiber Bragg grating (FBG) was used as the mechanically tunable element enabling the rapid wavelength sweeping of the laser center wavelength. A simple algorithm to process the noisy acquired data and identify the peak of the BGS spectra was employed. For the first time, this type of configuration was used to reliably interrogate at least three fiber Bragg grating sensors with a standard wavelength spacing between the Bragg wavelengths of 3 nm, without risk of breaking the stretched fiber, using an FBG with a simple PZT driven mount as the tuning elements. 相似文献
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Q. Sun D. Liu J. Wang H. Liu L. Xia P. Shum 《Applied physics. B, Lasers and optics》2009,96(4):833-841
We propose and experimentally demonstrate a time-division-multiplexing-based (TDM-based) multi-point abnormal-temperature
warning sensor system with different thresholds. A multi-channel fiber Bragg grating (FBG) serving as the wavelength selector
is employed in the fiber ring laser to generate a multi-wavelength pulsed light source. The sensor array is composed of multiple
uniform sensing FBGs at different positions and with different nominal wavelengths. The warning signal is obtained by only
monitoring the time slot between the injected pulse and the reflected pulse. The measurement range and resolution are theoretically
discussed and experimentally demonstrated. 相似文献