Three-dimensional surface topography measurement method and system based on optical microscopy

Abstract

The invention discloses a three-dimensional surface topography measurement method and system based on optical microscopy, which relate to the field of micro nano object measurement. The method comprises steps: a measured surface is placed in an observation range of an optical microscope, an appropriate objective lens and a lighting system are selected, an objective lens driving system is used to drive the objective lens and the measured surface to perform longitudinal relative motion, and during a serial layer scanning process, an image acquisition module is used to acquire a sequence image, and the depth position information when each image is acquired is recorded at the same time; a focusing evaluation algorithm is used to calculate the definition value of each pixel point in the sequence image; and according to the change condition of the focusing degree of the pixel point in the image sequence, a depth calculation algorithm is used to calculate the depth information of each pixel point, and thus, three-dimensional coordinates of the pixel point are thus acquired. The method and the system are applicable to the micro nano object measurement field, the surface waviness and the roughness can be measured, the three-dimensional surface topography data are rebuilt, the material surface texture information can be acquired, and the method and the system can be used for measuring a complex surface.

Description

technical field [0001] The invention relates to the field of micro-nano object measurement, in particular to a three-dimensional surface topography measurement method and system based on optical microscopy. Background technique [0002] The surface is the boundary between the object material and the surrounding medium, and the engineering surface generally refers to the boundary between metal, plastic, etc. and air. The traces of various processing processes shown by modern engineering surfaces are called surface topography in the field of surface metrology. Surface topography is an important determinant of the performance of parts. It not only has a great influence on mechanical properties such as friction and wear, contact stiffness, fatigue strength, fit properties, and transmission accuracy of the mechanical system, but also has a great relationship with thermal conductivity, electrical conductivity, and corrosion resistance. and other physical properties are closely re...

AI Technical Summary

Problems solved by technology

The existing optical microscopy methods mainly include interference microscopy (PSI, CSI) and confocal microscopy (CM). Due to the limitation of the principle, these two methods can only be illuminated by a coaxial light source, and it is difficult to measure the Object surface, the detection accuracy is greatly affected by the surface condition (material, color, reflectivity, roughness, etc.)

[0005] In summary, there is a lack of a measurement method in the prior art, which can measure the horizontal resolution and vertical resolution on the surface of an object, obtain the texture of the surface, and use it for the detection of special surfaces

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