投影栅相位法检测技术中抽样定理的适用性

分析了对于正弦信号抽样定理的适用性，给出了频谱分析时频域不发生泄漏的信号抽样条件。针对投影栅相位法三维检测技术中的抽样问题，提出了不移频处理方法和全场参考面的概念，避免了频域移频所带来的系统误差，克服了对正弦信号抽样的限制条件，并实例验证了新方法的优越性。该文的结论丰富了经典抽样定理的内容，提高了投影栅相位法三维检测技术的解相精度和稳定性，使之更符合实际应用条件。

Applicability of sampling theory in detect technique by phase approaching of projected grating

The problems of applicability and restriction of sampling theory in sinusoidal signal were analyzed and the sampling restrictions under which the leak will not occur in frequency domain were proposed in this paper. The avoiding frequency moving algorithm in frequency domain and the concept of full field reference plane were proposed aiming at the sampling process in detect technique by phase approaching of projected grating. It breaks through the restriction of classical sampling theory and eliminates system error coming from frequency moving in frequency domain. A test results proved its merits. The conclusions enrich the content of classical sampling theory, improve precision and stability of phase demodulation process and make it more convenient to application of the detect technique.