用激光二极管自混合干涉测量距离  

Measurement of distance by laser diode self-mixing interference

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：《物理实验》2013年第1期26-29,共4页Physics Experimentation

摘　　要：通过改变激光二极管工作电流,利用自混合干涉信号的相位变化来测量外腔长度.激光二极管工作电流变化导致激光频率变化.工作电流变化引起的干涉信号的相位变化与外腔长度成正比.干涉信号的相位变化2π,对应光频变化的等效长度的1/2.由于改变工作电流激光二极管激光光频可调节范围远小于激光频率,光频变化的等效长度远大于激光波长,激光二极管自混合干涉测量距离的精度远小于测量位移的精度.The external cavity length was measured by changing the laser diode operating current and measuring the phase shift of self-mixing interference signal. The change of laser diode operating current leaded to the change of laser frequency. The variation of the signal phase due to the change of operating current was proportional to the length of external cavity. Because the frequency shift caused by the operating current adjustment was very small compared to the original laser frequency, the e- quivalent length of the optical frequency change was much bigger than the laser wavelength. By laser diode self-mixing interference, the precision of distance measurement was far less than that of dis- placement measurement.

关 键 词：激光二极管 自混合干涉 激光频率调制 外腔长度 距离测量 位移测量 

分 类 号：O436.1[机械工程—光学工程] TN248.4[理学—光学]