摘要
大尺度、高精度的绝对距离测量在卫星编队飞行、自由空间通信、大尺寸工件检测等前沿应用中具有举足轻重的作用.本文利用飞秒激光脉冲的飞行时间方法对一段52m的大气传输路径进行了绝对距离测量.通过平衡光学互相关技术探测目标反射脉冲与参考脉冲之间的时间误差,并利用得到的平衡互相关电压信号反馈控制谐振腔长,将脉冲间隔的整数倍精确锁定至往返距离,最后由飞秒激光的重复频率确定目标反射脉冲的飞行时间.这一测量方案有效地避免了直接光电探测造成的飞行时间分辨率的损失.实验中,采用工作在1.04μm波段的高重复频率掺Yb锁模光纤激光器作为飞秒激光源,在1s的平均时间下获得了12nm的测量精度.
High-precision distance measurement in a long range is critical for many advanced applications, such as satellite formation flying, free space optical communication and large scale machining. A 52 m absolute distance measurement in free space based on time of flight of femtosecond laser is demonstrated. The timing offset between target-reflected and the reference pulses is precisely characterized by balanced optical cross-correlation method. The balanced cross correlation signal is used for the feedback control of the cavity length and tightly locks the distance under test to multiple of pulse separation. As a result, the time of flight of the target-reflected pulse is determined by the repetition rate of the femtosecond laser, which effectively avoids the loss of timing resolution caused by direct access of pulse time-of-flight from photo-detection. In the experiment, a Yb -doped high repetition rate mode-locked fiber laser working at 1.04 μm is used as a femtosecond laser source, and a measurement precision of t2 nm is achieved in an average time of one second.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第24期102-108,共7页
Acta Physica Sinica
基金
国家重点基础研究发展规划(批准号:2011CB808101
2010CB327604)
国家自然科学基金(批准号:61078028
61008015
61205131
11274239)
高等学校博士学科点专项科研基金(批准号:20110032110056)资助的课题~~
关键词
平衡光学互相关
飞秒
测距
卫星编队飞行
balanced optical cross-correlation, femtosecond, distance measurement, satellite formation flying
