A Doppler Optimal Imaging Method for Sinusoidal Phase Difference Demodulation

Abstract

The invention discloses a Doppler optimization imaging method for sinusoidal phase difference demodulation, which comprises the following steps: 1) performing two-dimensional scanning imaging on a biological sample to be measured with high-speed movement and large vibration amplitude; 2) extracting a two-dimensional interference spectrum The phase information of the complex tomographic signal after the signal is Fourier transformed along the wavenumber domain, and the phase information of the adjacent signal acquisition time intervals are differentially processed one by one to obtain the two-dimensional tomographic phase difference item; 3) Decompose the sinusoidal phase difference 4) Reconstruct the Doppler differential phase and the amplitude part of the original two-dimensional complex tomography signal into a two-dimensional differential tomography signal, where the phase is is the Doppler image of the measured biological sample changing with time. The invention has both the problem that the traditional Doppler OCT system is difficult to accurately measure the motion information of the high-speed motion and large-amplitude motion samples, and the characteristics of de-mirroring and high precision of the sinusoidal phase modulation OCT system.

Description

technical field [0001] The present invention relates to the technical field of Fourier-domain Optical Coherence Tomography (OCT for short), in particular to a sinusoidal phase modulation complex frequency domain Doppler optical coherence tomography method. Background technique [0002] Optical coherence tomography OCT (optical coherence tomography, OCT) is an imaging technology with high-resolution, non-destructive, real-time imaging capabilities and broad application prospects. [0003] OCT technology is divided into time-domain OCT technology and Fourier domain OCT technology (He Ziang. Research on FD-OCT Decomplex Conjugate Imaging [D]. Zhejiang University School of Information, Zhejiang University, 2008). Since the reflection or scattering signal in the deep layer of the biological sample can detect the very weak backscattered light returned by the sample (Li Peng. Theoretical and Experimental Research of Optical Coherence Tomography [D]. Nanjing University of Science an...

AI Technical Summary

Problems solved by technology

[0008] The complex frequency domain OCT technology based on sinusoidal phase modulation provides a solution for the dynamic image measurement of high-speed vibrating samples such as cardiovascular systems, but the signal-to-noise ratio and modulation frequency of the system are limited, making it difficult to obtain higher speeds Detection sensitivity

Because when imaging living organisms, the large-amplitude and high-speed motion in the measured sample will cause the time-spectrum after Fourier transform to alias (that is, frequency mixing), although the traditional sinusoidal phase demodulation method is more accurate than the traditional Fourier domain OCT technology The signal-to-noise ratio is improved, but it is limited by the modulation frequency brought by the Fourier analysis process, which will make it difficult to obtain the Doppler image of the sample to be tested in an environment with various noise frequencies

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