用于激光相控阵的阵列相位调制器研究

分析了相位调制器在激光相控阵中的重要性,提出了阵列相位调制器的设计思想.对退火质子交换(annealed proton-exchanged,APE)光波导折射率进行了理论分析,利用光束传输法仿真模拟了APE波导折射率分布和模场分布,优化设计了级联Y分支波导结构,实现了光功率的高均匀输出.基于铌酸锂晶体的电光效应,对影响半波电压的因素进行了分析,设计了长电极结构,理论上得到了低半波电压.基于退火质子交换工艺制作了阵列相位调制器,并对器件的光学特性和电学特性进行了实验测试,测得器件的插入损耗为6.83 dB,光功率输出均匀性为0.23 dB,4路半波电压分别为2.1、3.4、2.0、2.1 V.结果表明:该器件的制作有助于激光相控阵的集成化.

Arrayed Phase Modulator Based on Laser-Phased-Array

The phase modulator is important in laser phased array. The arrayed phase modulator based on optical waveguide is proposed. The index profile in annealed proton-exchanged( APE) LiNb03 waveguide is studied theoretically and simulated by beam propagation method( BPM). High uniformity of output power is gained numerically by optimized design of cascaded Y-branch. The structure with long electrodes is designed to obtain low half-wave voltage. The 1 × 4 arrayed phase modulator is finally fabricated using APE technology. The optical and electrical properties are tested. The insertion loss is 6. 83 dB,the uniformity of output power is 0. 23 dB,and the voltages are 2. 1,3. 4,2. 0,and 2. 1 V,respectively,which indicates that the arrayed phase modulator can satisfy the theory and expectation well.