[工学]集成光学课程第八章-1.ppt

Electro-Optic Modulators 8.1 Basic Operating Characteristics of Switches and Modulators 8.2 The Electro-Optic Effect 8.3 Single-Waveguide Electro-Optic Modulators 8.4 Dual-Channel Waveguide Electro-optic Modulators 8.5 Mach-Zehnder Type Electro-Optic Modulators 8.6 Electro-Optic Modulators Employing Reflection or Diffraction 8.7 Comparison of Waveguide Modulators to Bulk Electro-Optic Modulators 在本章将学到 单波导电光调制器的工作原理 双沟道波导电光调制器的工作原理 波导调制器比“体”调制器更为优越 如何设计波导电光调制器 modulator：调制器 switch：开关 modulation depth：调制深度 bandwidth：带宽 insertion loss：插入损耗 power consumption：功率损耗 isolation：隔离度 Pockels effect：普克尔效应 Kerr effect：克尔效应 indicatrix：指标线；光率体 index ellipsoid：折射率椭球 centrosymmetric：中心对称的 single-waveguide electro-optic modulators：单波导电光调制器 phase modulator：相位调制器 polarizer：起偏器 polarization –selective filter (usually called an analyzer)：检偏器 intensity modulator：强度调制器 electro-absorption modulator：电致吸收调制器 Franz-Keldysh effect：弗兰茨－凯第希效应（当一半导体材料中存在强电场时，材料的吸收光谱向长波方向移动） direct bandgap material：直接带隙材料 depletion layer：耗尽层 Mach-Zehnder interferometer：马赫---泽德干涉仪 Permittivity：介电常数 This chapter begins the discussion of optical-signal modulation and switching. In many cases, the same device can function as either a modulator or a switch, depending on the strength of the interaction between the optical waves and the controlling electrical signal, as well as on the arrangement of input and output ports. The device is considered to be a modulator if its primary function is to impress information on a light wave by temporarily varying one of its properties. A switch, on the other hand, changes the spatial position of the light, or else turns it off and on. 8.1 Basic Operating Characteristics of Switches and Modulators One important characteristic of modulators and switches is the modulation depth, or modulation index, ?. In the case of an intensity modulator in which the applied electrical signal acts to decrease of the transmitted light, ? is given by 8.1.2 Ba