Sub-micron scale glass subsurface defect detection device and method

Abstract

The invention discloses a sub-micron scale glass subsurface defect detection device and method. A light source part of the device comprises a super-continuum luminous spectrum light source and a single-mode optical fiber circulator; a reference arm and sample arm part comprises a first collimating lens, a 45-degree cylindrical reflecting mirror, a reference objective, a reference reflecting mirror, a two-dimensional scanning galvanometer, a sample objective and a part to be detected; a detection arm part comprises a second collimating lens, a transmission grating, a focusing lens, a photoelectric detector and a computer. The method comprises the steps that light of a reference arm and light of a sample arm return back to the single-mode optical fiber circulator in the same way, light beams of the two arms encounter, and interference is caused; interfered light beams are subjected to light splitting through the transmission grating and then focused on different pixel elements of the photoelectric detector through the focusing lens, the photoelectric detector inputs collected signals into the computer, the signals are processed, and faultage images of different positions are obtained. According to the sub-micron scale glass subsurface defect detection device and method, the ultra-wide band light source, the high-power aperture imaging objectives and the common light path imaging structure are adopted, and the three-dimensional structure of sub-micron scale glass subsurface cracks is obtained.

Description

technical field [0001] The invention relates to the technical field of optical coherence tomography (Optical Coherence Tomography, OCT), in particular to a submicron-scale glass subsurface defect detection device and method. Background technique [0002] Optical coherence tomography (Optical Coherence, OCT) is a non-invasive, non-invasive, high-resolution, high-sensitivity real-time imaging method applied to biological tissues. In 1991, the Fujimoto research group at the Massachusetts Institute of Technology used a superluminescent diode with a center wavelength of 830nm as the light source, and used an optical low coherence reflectometer (OLCR) to image biological tissues, and proposed optical coherence tomography for the first time. concept. The device is mainly based on the low-coherence imaging of Michelson interferometer, so the device uses a broadband light source, the light returned from the reference arm and the backscattered light returned from different depths of ...

AI Technical Summary

Problems solved by technology

The early optical coherence tomography called time-domain OCT has certain limitations: the requirements for mechanical devices are too high and the cost is too expensive

The traditional methods for judging cracks include corrosion method and surface roughness measurement method. The corrosion method destroys the shape of the crack itself, and can only determine the lateral position of the crack, but cannot obtain its extension depth; the method of measuring surface roughness can obtain the surface roughness of the glass. Thus estimating the maximum depth of glass cracks, local data cannot be obtained

The optical imaging methods used to detect glass cracks mainly include total internal reflection microscopy, confocal microscopy, etc., but due to limitations in imaging resolution and imaging depth, it is difficult to achieve sub-micron glass subsurface cracks. Three-dimensional detection of cracks of magnitude

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