發(fā)布時間：2018-02-13 10:47

  本文關(guān)鍵詞： 細(xì)徑保偏光纖耦合器 熔融拉錐 高精度對軸 蠕變建模 拉力控制　出處：《哈爾濱工業(yè)大學(xué)》2015年博士論文　論文類型：學(xué)位論文

【摘要】：保偏光纖耦合器是應(yīng)用保偏光纖制作的光纖耦合器,是實(shí)現(xiàn)線偏振光耦合、分用以及復(fù)用的關(guān)鍵器件,是組成光纖陀螺的重要器件。在保偏光纖器件制造中采用細(xì)徑光纖不僅可以減小器件體積,增加光纖陀螺的集成化程度,降低生產(chǎn)成本和光纖溫度敏感,而且能夠提高光纖陀螺的性能。采用細(xì)徑保偏光纖是光纖器件發(fā)展的重要趨勢,因而研究細(xì)徑保偏光纖耦合器的制造具有重要意義。隨著光纖直徑向幾十微米尺寸延伸,不利于光纖對軸和熔融拉錐的很多特性突顯,例如光纖易于彎曲扭轉(zhuǎn)、強(qiáng)度降低和幾何尺寸減少等,并且熔融拉錐過程對各物理量的控制要求更加精密,因而對保偏光纖對軸和熔融拉錐過程中拉力、溫度和速度等各物理量的控制提出了更高的要求。本文對細(xì)徑保偏光纖耦合器熔融制造中的關(guān)鍵技術(shù)進(jìn)行研究,從細(xì)徑保偏光纖的高精度對軸、熔融拉錐蠕變建模、拉力控制及加熱方式等四個方面進(jìn)行深入研究,并且最后在此基礎(chǔ)上建立細(xì)徑保偏光纖耦合器制造實(shí)驗(yàn)平臺。在保偏光纖高精度對軸方面,建立細(xì)徑保偏光纖的折射率模型,利用有限元軟件對細(xì)徑保偏光纖的側(cè)向成像進(jìn)行仿真,通過對仿真結(jié)果分析選擇焦點(diǎn)附近的最大光強(qiáng)變化檢測保偏光纖的偏振軸。提出一種光纖與電動平臺旋轉(zhuǎn)中心同軸度的調(diào)節(jié)方法,經(jīng)圖像處理得到光纖圖像的輪廓,采用最小二乘法計(jì)算出光纖中心的直線方程,得到光纖中心與電動旋轉(zhuǎn)中心的距離。采用基于閾值的圖像清晰度函數(shù),確定顯微鏡檢測的位置,然后將采集的數(shù)據(jù)進(jìn)行傅里葉濾波和三次樣條擬合,得到保偏光纖偏振軸的位置。在光纖熔融拉錐蠕變建模方面,光纖熔融拉錐的過程是光纖蠕變的過程,分析粘彈性材料的玻璃化溫度及假定溫度、力學(xué)性能以及簡單熱流變特性。通過拉伸實(shí)驗(yàn)測得光纖的玻璃化溫度,采用廣義Maxwell模型描述光纖材料在變溫下的應(yīng)力松弛。測量光纖材料的蠕變恢復(fù)曲線,以遲緩矩為約束條件,采用有條件最優(yōu)化搜索求解光纖材料的遲緩模量系數(shù)和遲緩時間,建立遲緩模量與松弛模量的關(guān)系,得到松弛模量系數(shù)和松弛時間。由松弛模量和蠕變?nèi)崃康木矸e關(guān)系建立光纖的蠕變模型,對兩個溫度的蠕變模型數(shù)值求解,最后建立光纖蠕變和蠕變速率模型。在光纖熔融拉錐拉力控制技術(shù)方面,設(shè)計(jì)保偏光纖熔融拉力控制裝置。該控制裝置由計(jì)算機(jī)、拉伸機(jī)構(gòu)、圓光柵和電磁力控制電路等組成,通過檢測光纖支架的旋轉(zhuǎn)角度,改變線圈中的電流,實(shí)現(xiàn)對拉伸力的實(shí)時控制。建立拉伸機(jī)構(gòu)的三維空間模型,計(jì)算永磁鐵的空間運(yùn)動軌跡,對永磁鐵和線圈之間的電磁力進(jìn)行三維有限元仿真,從理論仿真驗(yàn)證該控制方法。設(shè)計(jì)電磁力的控制電路,建立拉力和電磁力的關(guān)系,最后通過實(shí)驗(yàn)建立線圈中的電流、支架旋轉(zhuǎn)角度和光纖支架拉力的關(guān)系,實(shí)現(xiàn)熔融拉錐過程的拉力控制。最后,建立細(xì)徑保偏光纖耦合器制造平臺。對細(xì)徑保偏光纖耦合器的制造工藝進(jìn)行研究,設(shè)計(jì)一個采用高壓電弧的加熱源,采用電壓閉環(huán)和電流控制,通過電弧控制電壓控制電弧放電電流。采用紅外熱像儀對弧區(qū)溫度進(jìn)行測量,建立弧區(qū)溫度與放電頻率、電弧控制電壓和加熱距離的關(guān)系,檢測高壓電弧的最高溫度及其加熱穩(wěn)定性。利用有限元方法對熔融拉錐前進(jìn)行預(yù)熱分析。設(shè)計(jì)了光纖夾持夾具,研究熔融拉錐速度的控制策略和消光比測試光路,最后制造出非匹配型細(xì)徑保偏光纖耦合器。
[Abstract]:Polarization maintaining fiber coupler is used polarization preserving coupler production, is the realization of linear polarization coupling, and with key component reuse, is an important component of fiber optic gyro. In polarization maintaining fiber device fabrication using fine fiber can not only reduce the size of the device and increase the degree of integration of fog, reduce the production cost and the optical fiber temperature sensitive, and can improve the performance of fiber optic gyroscope. Small diameter polarization maintaining fiber is an important trend of development of the optical fiber device, which is of great significance to study fine diameter polarization maintaining fiber coupler manufacturing. With the diameter of fiber extending to tens of microns in size, is not conducive to highlight the many properties of fiber on axis and fused taper for example, easy to fiber bending torsion, reduce the strength and size reduction, the stretching process and the melting control of each physical quantity requires more precision, thus the polarization maintaining The fiber axis and the melt tension cone process, put forward higher requirements to control the temperature and the speed of the physical quantity. In this paper, the key technology of fine polarization maintaining fiber coupler in the manufacture of melt, from fine polarization maintaining fiber of high precision shaft, FBT creep modeling, four pull control and heating mode are studied deeply, and finally on the basis of the establishment of small diameter polarization maintaining fiber coupler manufacturing experiment platform. In polarization maintaining fiber in high precision shaft, a fine polarization maintaining fiber refractive rate model of fine polarization maintaining fiber lateral imaging are simulated using the finite element software. Through the analysis of simulation results to select the maximum intensity near the focus of inspection and polarization maintaining fiber axis. A fiber optic and electric platform rotation center coaxiality adjusting method, obtained by image processing of optical fiber image contour, By using the least squares method to calculate the linear equation of the center of the optical fiber, fiber center and the center of rotation of the electric distance. The image sharpness function based on the threshold to determine the microscope detection position, then the data will be collected by Fu Liye filter and three spline fitting, get the optical fiber polarization axis position. The coupler creep modeling, process of optical fiber fused fiber is the process of creep analysis, the glass transition temperature of the viscoelastic material and assumed temperature, mechanical properties and thermal rheological properties. The glass transition temperature by tensile test of optical fiber, the generalized Maxwell model to describe the stress relaxation in the temperature of the fiber material. Creep measurement fiber material recovery curve, with slow moment constraints, using the condition of optimal search solution for fiber material retardation coefficient and modulus of slow time, construction The relationship between vertical delay modulus and relaxation modulus, relaxation modulus coefficient and relaxation time. Creep model is established by the optical convolution relationship between relaxation modulus and creep compliance and creep model of numerical solution of two temperature, finally establish fiber creep and creep rate model. In the optical fiber taper tension control technology. Design of polarization maintaining fiber melt tension control device. The control device is composed of a computer, drawing mechanism, circular grating and electromagnetic force control circuit, through the rotation angle detection optical fiber bracket, change the current in the coil, to realize the real-time control of tensile force. Establish 3D model drawing mechanism, calculating the space trajectory of permanent magnet the three-dimensional finite element simulation of the electromagnetic force between the magnet and the coil, the control method is verified from simulation. The design of control circuit of the electromagnetic force and electromagnetic force was established 鍔涚殑鍏崇郴,鏈，

本文編號：1507982