基于垂直腔面发射半导体激光器的自混合测速实验

摘要

The self-mixing interference based on a Vertical-cavity Surface-Emitting Laser(VCSEI) was investigated. By taking a VCSEL as the source of a self-mixing interferometric system, the effect of different types of scattering surfaces and injection currents on the self-mixing signals was analyzed. It is concluded that the black and glossy photographic paper target will bring unfavorable influence on the self-mixing velocimeter and the operating currents with l- 1.4 times of the threshold currents can offer a self-mixing signal with a stable and great amplitude. For the longer preheating time, the power-up time of self-mixing velocimeter was discussed, and the results show that Doppler frequency will be stable and accurate after 17 s. The obtained results provide instructions for the parameter optimization and the choice of light source of a self-mixing velocimeter using the VCSEL.%针对激光自混合速度传感应用,采用新型垂直腔面发射激光器作为自混合干涉系统光源,对采用不同散射表面类型和工作电流所获得的自混合测速实验结果进行了研究.研究结果表明,黑色相纸材质的散射表面会对自混合信号产生不利影响;选择激光器的工作电流在阈值电流1～1.4倍时能获得较大且稳定的自混合信号.考虑该测速系统实际应用中存在开机预热时间,讨论了激光自混合系统的开机重复度.结果表明,开机后17 s左右,频率计计量的多普勒频率趋于准确和稳定.此研究结果可为垂直腔面发射半导体激光器自混合测速系统的光源选择和参数优化提供指导.