Comparator based on white light interference positioning principle and detection method thereof

Abstract

The invention discloses a comparator based on a white light interference positioning principle and a measurement method thereof. The comparator comprises a measurement probe, a measurement objective lens, an interference microscope, a vertical scanning working table, a sliding block, a CCD (Charge Coupled Device) imaging unit, a stand column, a movement amount detection unit and a horizontal working table, wherein the vertical scanning working table is arranged on the stand column and is driven by a rough drive mechanism up and down; the interference microscope and the CCD imaging unit are fixed onto the sliding block of the vertical scanning working table and driven by a fine drive mechanism up and down; the movement amount detection unit is used for detecting and outputting the movement amount of the sliding block; the measurement probe is arranged on a supporting rod vertically connected with an interference microscope body in a way that the measurement probe can rotate around a pivot shaft, and is used for being contacted with a measured object; and the measurement objective lens is used for gathering light and forming interference stripes. The high-precision characteristic of white light interference positioning can be made full use of to obtain a height measurement result through the comparator, and meanwhile, the comparator has the characteristics of simple structure, convenience in operation, high measurement precision, low cost and the like.

Description

technical field [0001] The invention belongs to the technical field of optical measurement of linear dimensions, and more specifically relates to a comparator based on the principle of white light interference positioning and a measurement method thereof. Background technique [0002] During the processing and inspection of mechanical products, the measurement of length, thickness, height or other similar linear dimensions is an important content in geometric metrology. For high-precision linear dimension measurement, the comparative measurement method is a widely used measurement method whose measurement accuracy has been continuously improved. At present, the length comparison measurement methods mainly include mechanical comparators, optical comparators, inductance micrometers and grating measuring instruments. The mechanical comparators mainly include lever comparators, lever gear comparators and torsion spring comparators. These three comparators amplify the measured ...

AI Technical Summary

Problems solved by technology

For example, for the comparative measurement of the nanoscale length of precision and tiny parts, it is difficult for the above-mentioned instruments to achieve the required measurement resolution, or it is difficult to perform installation measurement

In addition, although a dual-frequency laser interferometer can be used to meet the measurement requirements of various instruments in the above-mentioned comparative measurement method, and even improve the measurement resolution to a higher level, its price is high and the volume is large, and it is difficult for general units to do so economically. Tolerance, and its operation is complicated, and has high requirements for measuring personnel, so it is difficult to construct a reasonable high-precision measurement scheme for precision parts in practice

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