为了提高硅基上单模波导器件与单模光纤的耦合效率和工艺容差 ,设计了一种实用新型光斑转换器 ,它由水平和垂直双向楔变的波导芯区和双内包层构成 .分析了内包层折射率与其厚度对耦合效率的影响 ,发现通过优化内包层的参数可以加强对扩展光场的限制 .针对在硅基上制作垂直楔变结构的波导还很困难的情况 ,提出了一种低成本、简单可行的制作方法 In order to improve the coupling efficiency and process tolerance of the single-mode waveguide device and the single-mode fiber on a silicon substrate, a practical new type of spot converter is proposed, which is composed of a horizontal and vertical wedge-changing waveguide core region and a double inner cladding. The effect of the inner cladding refractive index and its thickness on the coupling efficiency is studied. It is found that the limitation of the extended optical field can be enhanced by optimizing the inner cladding parameters. In view of the difficulty in fabricating the waveguide with vertical wedge structure on the silicon base, Low cost, simple and feasible method of making