【作者】 赵飞；

【导师】 董玮；

【作者基本信息】 吉林大学 ， 电路与系统， 2010， 硕士

【摘要】 可调谐光学滤波器是现代宽带光网中的一种核心器件,在波分复用光纤网络中,它可将光纤中不同波长传输的信号进行复用或解复用,或者在光网络中用作光插、分复用器。本论文的主要工作包括可调谐光滤波器的理论设计,可调谐光滤波原理分析与计算,F-P腔尺寸设计,滤波器性能模拟,静电驱动理论计算,电极施加位置方案比较,ANSYS理论模拟,包括静力学分析和动力学分析等。首先主要对可调谐滤波器的主体部分进行光学结构设计,主要包括F-P腔和DBR反射镜的结构设计。SOI脊型波导的结构设计,基于这些光学结构参数,模拟了该滤波器的性能,并给出了调谐状态下的频移特性。其次,滤波器的结构由SOI光波导、两个DBR反射镜、用于构成F-P腔的硅平台、平台上的电极和支撑梁组成,从滤波器的性能出发确定DBR镜和F-P腔的尺寸,从需要调谐的波长范围计算中间硅平台需要改变的折射率的大小进而计算出电极尺寸以及需要的功耗。在以上工作的基础上利用电磁学、结构动力学、有限元方法等为理论基础,对微机械静电梳状电极两端加电压所产生的静电力,以及静电力所形成的DBR移动电极的形变进行理论分析。再次,对于由两个或多个工程物理场之间相互作用形成的耦合场仅仅依靠理论计算远远不够,我们采用ANSYS有限元分析软件对该耦合场进行模拟,模拟结果与理论设计基本符合。最后对整体模型动态模型进行分析,主要分为模态分析和瞬态动力学分析,寻求整体模型固有频率和主振型,从而了解模型的振动特性,并且分析结构的响应,以计算结构振动时的达到稳态时间和变化规律。更多还原

【Abstract】 Tunable optical filter is a frequency selective device; you can also say that it is a wavelength selection device. Its main purpose is to extract specific frequencies or wavelengths of light from the mixed signals, which includes many different frequencies of light waves. A good performance tunable optical filter should have a narrow bandwidth to allow the channel spacing is small, wide FSR and narrow half-height to accommodate more channels, fast wavelength switching speed, wide wavelength stability and high precision etc.The main work of this thesis includes design of the tunable optical F-P filter based on electrostatic driving, the calculation of static drive and ANSYS simulation. First, design the main part of the tunable filter for optical structure, filter structure includes the input and output light waveguides, two symmetric DBR, silicon waveguide F-P resonator, MEMS electrostatic comb electrodes etc. I expound the design of the F-P cavity and the DBR mirror structure and SOI ridge waveguide structure. Based on these optical structural parameters, simulate the performance of the filter and gives the frequency shift tuning characteristics. Second, the silicon platform of F-P cavity make up of the optical waveguide and two DBR mirrors, the platform is connected by elastic beam and the electrode. Starting from the filter performance to determine the F-P cavity and DBR mirror, calculate the middle of silicon platforms change, which affects the refractive index, by the wavelength tuning range and then calculated the size of electrode size and the need for power. Based on the above work, using the electromagnetic, structural dynamics, finite element method theory to design the comb electrode, analyze that the voltage, which loads to the MEMS electrostatic comb electrode, generate the, and the electrostatic force moves electrode DBR. I calculated the natural frequency, sensitivity and vibration electrode with no damping and damping conditions. Again, for two or more works by the interaction between the formations of physical coupling field calculation alone is not enough. We used ANSYS finite element analysis software to simulate the coupling field, modeled the overall movable electrode, and simulation. Static analyzed and calculated the response of structures with the fixed load, the simulation results agreed with the theoretical design. Finally, analyze the dynamic model, including modal analysis and transient dynamic analysis, analyze the natural frequency and vibration mode, and understand the vibration characteristics of the model.The innovation of this design is the use of SOI waveguide, F-P cavity, electrostatic comb-shaped electrode integrated structure, compact novel, and is easy to integrate other optical components. This integration of photonic-based optical waveguide on silicon wafer polishing filter is a basic component interconnection unit, which is a key function in photonic integrated devices. In addition, the use of electrostatic comb electrode structure, two symmetric DBR while moving, by adjusting the cavity length of F-P cavity to achieve the equivalent function of the tunable filter has the characteristics of wide tuning range.Significance of this research is to study the design of ridge waveguide based on SOI, MEMS electrostatic drive, F-P cavity integrated in one tunable optical filter. When the comb-shaped electrode voltage is applied, with the effect of static electricity, movable electrode drive movable DBR, causing the F-P equivalent cavity length change, in order to achieve tunable filter function. In addition, re-discuses the static electricity application in the MEMS system. Although some of the static electricity in the micro-mechanical systems have been widely used and have been commercialized, its design concept and design tools have not been able to achieve the intended purpose. Combined with a variety of disciplines, intensive development of cutting-edge science of today’s results will make MEMS gradually from the laboratory to practical use.ANSYS as a major software design of this device is a widely used commercial package of engineering analysis software. Is the so-called "bricks without straw his tools." ANSYS is currently the most widely used, and also is the most powerful finite element software. We apply this software tunable optical filter to simulate the driving part, combined with today’s advanced algorithms and analysis of concepts, simulate electrode work situation. Therefore, using the software to analyze the MEMS system can find a good meeting point.Prospects for future work, considering the author’s level that can carry out specific research in the following: Sensitivity calculation extended to the filter part; Reduce the damping effect impacting on the system; Analysis of coupled field; Design drive circuit.更多还原