Endoscopic oct imaging system using optical path difference external compensation common path interference probe

Abstract

The invention discloses an endoscopic OCT imaging system adopting an optical path difference external compensation common-path interference probe, comprising a light source, an optical path difference external compensation interferometer, first and second acousto-optic frequency shifters, an optical circulator, and an optical fiber Rotary connector, spiral scanning mechanism, endoscopic probe, glass spacer rod, Green lens, 45° cylindrical mirror, transparent sealing sleeve, metal outer sheath, window, detector, data acquisition card and computer, etc. Use the front surface of the Rigling lens of the endoscopic probe as the reference surface, and the optical path difference between it and the sample is compensated by the optical path difference external compensation interferometer; the spiral traversal scanning method is used to reduce the missed detection of lesions, and the flat window is used to To eliminate the astigmatism usually caused by the cylindrical transparent sealing sleeve, the acousto-optic frequency shifter combined with signal filtering and demodulation technology is used to eliminate the artifacts in the imaging results. The invention has the characteristics of strong anti-interference ability, plug-and-play probe, reduced missed detection of lesions, no false image interference, no astigmatism in incident sample beams, and the like.

Description

technical field [0001] The invention relates to medical endoscopic imaging technology and optical coherence tomography imaging technology, in particular to an endoscopic optical coherence tomography imaging system adopting optical path difference external compensation common path interference endoscopic probe and helical scanning imaging mode. Background technique [0002] Through the endoscope, doctors can directly observe the tissue morphology and lesions of the internal organs of the human body, and can also perform surgical treatment on the lesions. Traditional endoscopes can only observe the surface morphology of internal organs, and lesions often occur inside the organs first. Many imaging techniques with tomographic capabilities, such as: computer tomography, nuclear magnetic resonance, X-ray and ultrasound, are playing an important role in clinical diagnosis, but these techniques can only provide 0.1-1mm resolution, which is far from the detection The level of resol...

AI Technical Summary

Problems solved by technology

The problems existing in these systems are as follows: 1) Only one imaging mode of spectral domain OCT is used, and there is no possibility of adopting frequency-sweeping OCT imaging mode, so different imaging modes cannot be used according to different application occasions to give full play to their respective advantages; 2) It is not traversing scanning imaging, and there is a possibility of missed detection of lesions; 3) The serious astigmatism problem that will be caused when the beam of incident sample passes through the cylindrical transparent sealing sleeve is not considered

[0005] In the frequency-sweeping OCT system proposed by Yang Yaliang et al. (Yang Yaliang et al., helical scanning co-path interference type endoscopic frequency-sweeping OCT real-time imaging method and system, invention patent: ZL2012100277848), the spectroscopic device and reference mirror are placed on the probe Internally, a common path interference endoscopic probe is formed, and a micro motor installed inside the probe is used to realize the helical scanning imaging at the top. The advantage of the top scanning is that it is stable, but the system still has the following problems: 1) Spectroscopic devices, reference mirrors, and the distance between the two to match the optical path of the sample beam, as well as the micro-motor, etc., make the unbendable part of the probe tip longer, which will make it difficult for the probe to pass through the oral cavity, the Y-shaped entrance of the electronic endoscope instrument channel, etc., so that it is not easy to into the body; 2) The micro-motor only performs helical scanning motion in the inner space of the tip of the probe, and the travel is very limited, which is difficult to meet the actual needs of lesion detection; 3) Only one imaging mode of frequency-sweeping OCT is used, and no spectral imaging mode is provided. 4) The astigmatism problem caused by the light beam passing through the cylindrical transparent sealing sleeve is not considered

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