一种单模垂直腔面发射激光器自混合测距系统研制

A Single-mode VCSEL Laser Range Finder with a Small Modulation and High Precision Using the Self-mix

摘要: 研究了一种小调制高精度单模垂直腔面发射激光器(VCSEL)自混合测距系统,根据单模VCSEL的特性曲线可知,其波长Δλ/ΔI非线性失真严重,且与调制电流幅度ΔI大小相关,该特性严重地影响系统的测距精度.通过对单模VCSEL进行小电流幅度调制以及采用专用的光电信号处理技术,明显提高了系统的测距精度.实验结果表明当使用调制电流幅度ΔIp-p=0.28 mA,调制频率fm=500 Hz对单模VCSEL进行频率调制,并且应用差频模拟锁相环(APLL)处理带有相位突变的自混合拍频信号,在采样时间为0.1 s,系统测距动态范围为50～500 mm,测距精度优于2 mm.

Abstract: A single-mode vertical-cavity surface-emitting laser range finder(VCSEL) with small modulation and high precision was described by using the self-mixing effect.According to the characteristic curve of single-mode VCSEL,the nonlinear distortion of Δλ/ΔI is severe and related with the modulation current ΔI,which worsens greatly the system ranging accuracy.The ranging accuracy of system was improved obviously by applying small current modulation of the single-mode VCSEL and specific circuits to pro..