数字投影中填充因子对相位测量影响分析

摘要

提出了数字投影的填充因子对相位测量的误差分析.在结构光三维测量中,数字投影容易改变条纹周期和产生准确的相移,因而到了越来越广泛的应用.然而相比传统的机械模拟投影方式,数字投影采用了抽样方式,且由于其自身结构的限制,填充因子不能做到100%,必然对相位测量有影响.针对填充因子对相位测量的误差,还没有人进行充分研究.对填充因子引起误差原因进行分析,并给出其数学描述,从而建立了理论依据,还进一步提出了离焦减少误差的方法,并给出了其数学表达.最后通过模拟实验的方法,对理论进行了验证,实验结果证明了填充因子减少将增大测量误差,离焦法可以减少相位测量误差.%In three-dimensional measurement, electronic projection technology has been more and more widely used.However,compared to traditional mechanical analog projection mode, the digital projection use sampling method, and because of its structural limitations,the fill factor can not be 100％ ,both of which will impact on the phase measurement. For the impact of sampling on the phase measuring, domestic and foreign scholars have done a great deal of research, but for the phase measurement error caused by the fill factor, no reference has been seen. We here present the phase measurement error analysis caused by the fill factor of digital projection, and give the detailed theoretical analysis. Also proposed is the method to reduce the error. Finally through the simulation method, the theory is verified. Experimental results also prove the correctness of the theory.