Nondestructive detection method for thickness of nacrelayer of pearl

Abstract

The invention discloses a nondestructive detection method for the thickness of a nacrelayer of a pearl. The nondestructive detection method comprises the following steps of gradually irradiating two objects to be detected through an X-ray radiation source to acquire two initial images; judging whether a pixel point is a boundary point according to a gray value of the pixel point, thus identifying all the boundary points of the images of the objects to the detected according to the initial images; for a standard sphere, fitting a circle by using the identified boundary points, and setting the radius of the circle as the radius R0 of an image of the standard sphere; for the pearl to be detected, fitting three concentric circles by using the identified boundary points, wherein the radius of the circle positioned at the center is used as the radius R2 of an image of a pearl kernel, and the radius of the circle positioned on the outmost side is used as the radius R1 of an image of the pearl to be detected; the radius r1 of the pearl to be detected is equal to mu R1, and the radius r2 of the pearl kernel is equal to mu R2, thus the thickness r of the nacrelayer is obtained by subtracting r2 from r1; a proportion coefficient mu is equal to r0 / R0; r0 is the radius of the standard sphere. According to the nondestructive detection method, the calculation of the thickness of the nacrelayer is realized, and a measurement result is more accurate.

Description

technical field [0001] The present invention relates to a method for detecting a pearl bead layer, in particular to a non-destructive detecting method for the thickness of a pearl bead layer using an X-ray radiation source. Background technique [0002] A pearl is an opaque small sphere, and it is easy for people to distinguish the color, luster, roundness, size and finish of the pearl from its appearance. If you want to understand the internal structure of the pearl, you can usually do it by punching or dissecting it, but doing so will destroy the pearl. [0003] With the development of computer technology, people mainly use X-ray technology and optical coherence tomography technology for non-destructive testing of pearls. These new achievements are applied to the field of pearl detection, which effectively solves the difficult problem of "pearl identification and quantitative detection". However, the current X-ray and optical coherence tomography technology has some defe...

AI Technical Summary

Problems solved by technology

However, the current X-ray and optical coherence tomography technology has some defects. Specifically, the general X-ray detection technology directly calculates the radius of the pearl through the image of the measured pearl, and there are errors in the measurement of various parameters in this process. , especially some parameters such as the distance from the ray source to the inner point B of the pearl cannot be measured, which makes it difficult to measure the radius r of the measured pearl 0 , the calculation result error cannot be controlled (such as figure 1 shown)

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