Discussion of Spatial Spectral Characteristic of Fourier Transform Method for Interfernce Fringe Analysis

Because of the global characteristic of the Fourier transform method for fringe pattern analysis, it has been extensively developed and widely used in optical metrology. Many other works were published afterward; however, the spatial spectrum characteristic of the Fourier transform method has not been fully and systematically investigated. The spatial spectrum characteristic and its relationship with factors such as the quantization of grey levels, random noise, and spatial carrier frequency are discussed. The results indicate that, the maximum bandwidth can be measured by the Fourier transform method is close to Nyquist sampling theorem. That provides a theoretical quantitative basis for the study of extending the measurement range of the Fourier transform method, also builds the relationship between the spatial frequency can be measured and the resolution of interferogram detector.