多纵模激光二极管自混合干涉的观察和分析  

Observation and Analysis on Self-Mixing Interference of Multi-Longitudinal Mode Laser Diode

作　　者：胡险峰[1] 

机构地区：[1]四川大学物理科学与技术学院,四川成都610064

出　　处：《光学学报》2010年第2期433-439,共7页Acta Optica Sinica

摘　　要：自混合干涉信号的幅度和波形均会随外腔静态长度发生周期性变化。实验测量了干涉信号幅度和波形随外腔静态长度的变化,并用多模自混合干涉信号叠加的方法计算分析了干涉信号的幅度随外腔静态长度的变化,然后考虑反馈光对内腔反射率和激光介质增益的影响计算分析了干涉信号的波形随外腔静态长度的变化。结果表明,多模激光自混合干涉信号随外腔静态长度变化的周期为内腔的光学长度,而其主极大区域的宽度为激光的相干长度,小于内腔的光学长度。多纵模自混合干涉信号的叠加导致自混合干涉信号的幅度随外腔静态长度发生周期性变化,而波形随外腔静态长度周期性变化则是内腔反射率和激光介质增益均受反馈光影响导致的非线性的结果。The amplitude and waveform of self-mixing interference signal change periodically with static length of external cavity. The changes of the amplitude and waveform are measured experimentally with variation of static length of external cavity. And,the variation of the amplitude with static length of external cavity is calculated by superposing of self-mixing interference signal of multi-longitudinal mode laser. Then,that variation of the waveform is analyzed by considering the effect of feedback light on reflectivity of laser-cavity and laser medium gain coefficient. Results show that,the variation period of self-mixing interference signal of multi-longitudinal mode laser with static length of external cavity is equal to optical length of laser cavity. While,the width of main maximum region of self-mixing interference signal with variation of static length of external cavity is equal to the coherence length of laser which is less than the optical length of laser cavity. The periodical variation of the amplitude with static length of external cavity comes from self-mixing interference of multi-longitudinal mode laser,and that of the waveform is caused by nonlinear effect produced from feedback light acted on laser cavity and laser medium.

关 键 词：光学测量 多纵模激光二极管 自混合干涉 相干长度 非线性效应 谱线宽度 

分 类 号：TN248.4[电子电信—物理电子学]