摘要
在采用结构照明的调制度测量轮廓术中 ,条纹的调制度对测量精度具有重要影响。本文讨论了结构光场的非正弦性对条纹调制度测量的影响并给出了影响规律 ,即相移次数为L时 ,只有n =mL± 1次谐波会对调制度产生影响 ,调制度误差频率为L倍基频频率 ,实验验证了这一规律的正确性。本文的工作对调制度测量轮廓术具有重要意义。
The existence of non-sinusoidal signal in structured light is unavoidable in 3D profilometry based on sinusoid grating,such as phase measurement profilometry (PMP) and Modulation Measurement Profilometry (MMP).Non-sinusoidal signal will influence the fringe modulation,which is very important to the measurement precision in MMP because the height information of the object is coded in the fringe modulation.In this paper,the influence of non-sinusoidal signal in structured light on the measurement precision of MMP is discussed.It is shown that only n=mL±1 levels harmonic will influence the modulation of fringe and the frequency of the error of fringe modulation is L times of fundamental frequency of the structured light if the phase-shifting step is L.Computer simulation and experimental results show that the measurement precision can be improved through five-step phase-shifting method when non-sinusoid signal exists.This work will be significant to MMP.
出处
《激光杂志》
CAS
CSCD
北大核心
2004年第1期26-28,共3页
Laser Journal
