【摘要】 利用 Ge 单晶良好的机械、声光性能,研制出工作中心频率为 70MHz、波长为 10.6ìm 的锗声光调制器。该器件采用高品质因数 Ge 单晶(III)作为声光介质, y36°切铌酸锂晶体作为压电换能器。由于锗器件对热变化特别敏感,所以设计了环绕结构和背面结构两种不同的吸热系统,测试表明,采用环绕结构比采用背面结构时衍射效率可提高 10%以上,而且光斑质量也明显变好。用 13W高频驱动功率驱动锗晶体声光调制器,其最大峰值衍射率达到 68%。更多还原

【Abstract】 A germanium acousto-optic modulator with 70MHz central operating frequency and 0.68ìm wavelength is developed according to acousto-optic modulation principle. The device uses high quality germanium single crystal (III) as acousto-optic media and y36° lithium niobate crystal as piezoelectric transducer. Since germanium device is very sensitive to heat variation, an absorbing heat system with circumferential structure is designed. The test result shows that the diffraction efficiency of the circumferential structure is 10% more than common double-plane heat absorbing structure and spot quality is better. The max diffraction efficiency of germanium acousto-optic modulator reaches 68%, when high frequency drive power (13W) is applied.更多还原