System and method for implementing gem identification based on Raman spectrum and OCT

Abstract

The invention discloses a system and a method for implementing gem identification based on Raman spectrum and optical coherence tomography (OCT). The system comprises a gem sample, a glass slide, a cassette, a mobile platform, a Raman spectrometer, an OCT, a data extraction and processing module and a display, wherein the cassette comprises two light holes. The method comprises the steps of firstly using OCT to acquire a no-load image via the light holes during no-load of the glass slide, and then separately using OCT and the Raman spectrometer to detect the sample on the glass slide, to acquire a sample spectrogram and an OCT image; using computer software to analyze the image to acquire boundary and distance information of the sample, completing the computation of a refractive index viaan optical path matching principle, and analyzing a Raman spectra to acquire a chemical property of the sample; and finally displaying a measurement result via the display. The system and method are simple in design, simple and convenient to operate, and achieve quick switching on measurement of the same sample; measurement and comprehensive analysis of multiple indexes such as physical property (optical refractive index) and chemical components of the irregular gem material are implemented; and meanwhile, the method achieves automation, digitization and intelligent measurement of optical refractive indexes of different faults of the gem.

Description

technical field [0001] The invention relates to the field of gemstone identification, in particular to a system and method for measuring the physical refractive index and chemical composition properties of gemstones based on Raman spectroscopy and OCT. Background technique [0002] The authenticity identification of gemstones is particularly important in real life, and the refractive index is an extremely important identification index. The measurement methods include prism method, polarization method (testing Brewster's angle), pin insertion method, Abbe refraction instrumentation, also including optical coherent imaging (OCT). [0003] OCT is a new technology for fast, high-resolution and high-sensitivity acquisition of high-resolution tomographic images of samples. It has been widely used in biomedicine and material detection. Its detection method is also very simple. Directly placed within the scanning range, the OCT image containing material characteristic information ...

AI Technical Summary

Problems solved by technology

[0004] The refractive index of jewelry and ore can be measured by this method, but only this one identification basis is relatively simple, especially in the case of samples with similar refractive index, it is difficult to distinguish jewelry materials, so it is necessary to enrich the corresponding identification indicators; and Raman spectroscopy As a mature technology, Raman spectroscopy can use the "molecular fingerprint" feature to identify different chemical components. As a semi-quantitative and non-quantitative technique, it is difficult to accurately quantify the content of different chemical components, but the refractive index can To make up for such shortcomings, the combination of the two technologies can exert greater power to form more comprehensive and comprehensive analysis results and reports on jewelry ore materials

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