电光聚合物波导中的锥形结构

提出并设计了一种基于电光聚合物的锥形波导,可用于单模光纤与电光聚合物波导器件之间的连接.锥形波导中采用了宽度锥形和折射率锥形结构.宽度锥形采用劈形形状,通过宽度和折射率的缓慢变化实现模场转换.劈形形状的宽度锥形具有较小的损耗且易于制作,折射率锥形可采用灰度掩膜光刻技术制作.研究了锥形波导的传输损耗与锥形波导的长度、波导宽度和厚度、材料吸收损耗等参数的关系及其优化,分析了锥形波导中的功率传输、模场分布与模式转换效率.结果显示锥形波导的传输损耗小于0.37 dB,光纤-波导-光纤的连接损耗优于1.62 dB,对插入损耗的改善达到8.78 dB,模场转换效率达到了83.7%.

Tapers in Electro-Optic Polymer Waveguides

A tapered electro-optic polymer waveguide is proposed and designed for coupling light between single-mode optical fiber and polymer waveguide. The tapered waveguide performs mode transformation between optical fiber mode and polymer waveguide mode by using a refractive index taper and a width taper with wedge profile. Wedge width taper possess smaller loss and is easy to make. The refractive index taper can be fabricated by utilizing a gray-scale mask lithography to control the UV light reaching each portion of the taper. The transmission loss of the tapers that depend on taper length, waveguide width and height, material loss are analyzed. The optimization of the design is discussed. The total power, mode distribution and its transformation through the taper are presented. The transmission loss of the taper is less than 0.37 dB, which results in an 8.78 dB insertion loss improvement and a low fiber-to-fiber component loss of 1. 62 dB. The mode transformation efficiency is 83.7% .