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As a high-precision detection technique of surface topography based on the interference theory of light, Phase-Shifting Interferometric is susceptible to vibration from the surrounding environment, which reduces the detection accuracy. In order to reduce the influence of vibration errors and improve the phase demodulation accuracy of measured wavefront, an anti-vibration phase demodulation method applied to Phase-Shifting Interferometric is proposed in this paper. This method first acquires two sequences of interference images with phase shifts of 0 and 𝜋𝜋/2 respectively, uses a digital image stabilization algorithm to suppress the vibration error of each frame in the sequence, and synthesizes two frames of interference images with phase shifts of 0 and 𝜋𝜋/2, respectively. Then, based on these two frames of synthesized images with determined phase shifts, the gradient algorithm and the Schmidt Orthogonal Transform are used for wavefront phase demodulation. The experimental results show that the percentage of pixels demodulated effectively at the truncated interface is more than 90%. Compared with the traditional demodulation method, the number of pixels demodulated effectively (demodulation accuracy) is improved.

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In order to reduce the vibration error of phase-shifting interferometry (PSI) and improve the demodulation accuracy of the wavefront phase, a demodulation method based on a component synthesis and gradient projection for PSI is proposed. For two sequences of interference images with a phase shift of 0, π / 2 , the method first corrects the vibration error by the pre-processing mechanism and multi-component synthesis. At the same time, two frames of interference images with a phase shift of 0, π / 2 are synthesized. Then the gradient projection algorithm is used to filter the background light of the synthesized image, and the wavefront phase is demodulated based on the arctangent operation. The experimental results show that the percentage of pixels demodulated effectively at the truncated interface is more than 90%. Compared with the traditional demodulation method, the number of pixels demodulated effectively (demodulation accuracy) is improved.

Based on the principle of low coherent light interference of optical fiber, a new method for detecting the distance between the mirror surfaces of a compound lens is proposed. Firstly, a system based on the principle of low coherent light interference is designed. Secondly, the frequency calculation method of interference signal of measurement system is put forward, and the band-pass filter is designed for interference signal to improve the signal-to-noise ratios. Based on the characteristics of low coherence light interference signal, the least squares symmetric peak location algorithm is proposed, which realizes the precise locating of the peak of the interferometric signal. Besides, the experiment of measuring the distance between the compound lens is carried out and the measurement error is analyzed.