Code micro-macro combined collection method of absolute grating ruler

Abstract

The invention discloses a code micro-macro combined collection method of an absolute grating ruler. The absolute grating ruler is a double-code-channel grating ruler with a low-accuracy encoding code channel and a high-accuracy encoding code channel which are arranged side by side. The code micro-macro combined collection method of the absolute grating ruler is characterized in that a cmos sensor is arranged on the absolute grating ruler, the cmos sensor comprises a multi-line scanning mode, an inclined scanning read-out mode and a parabola scanning read-out mode, one line of encode channel is scanned through the multi-line scanning mode, another line of encode channel is scanned through the inclined scanning read-out mode and the parabola scanning read-out mode , and the multi-line scanning mode, the inclined scanning read-out mode and the parabola scanning read-out mode are combined in a micro-macro mode to collect codes. The code micro-macro combined collection method of the absolute grating ruler achieves that a reading head of the absolute grating ruler carries out micro-macro combined reading, and meanwhile the collection time of each frame of image is shortened to achieve the collection of high frame frequency images. The code micro-macro combined collection method of the absolute grating ruler can improve the pollution-resistant capacity of the absolute grating ruler, and improves the reliability and correction rate of decoding.

Description

Technical field [0001] The present invention is an innovative technique of absolute grating scale macro compound collection method, which is an absolute grating scale macro compound collection method. Background technique [0002] The use of grating for displacement measurement should be chased until the 1950s. In a long period of question, it was used by astronomers and physicists as diffraction components as spectral analysis and optical wavelength measurement.Moire Fringes technology, its grid spacing is about 20um, and the accuracy is generally a few microns, but with the advancement of manufacturing technology.The current grating distance can reach O.8um and the resolution reaches LNM.Play an important role in the development of production and manufacturing.The nano -level grating measurement uses the diffraction grating, the grating distance is LUM or 0.8um. The width of the grid line is close to the wavelength of light, and the phenomenon of diffraction and interference c...

AI Technical Summary

Problems solved by technology

But the main disadvantage is that the measurement speed is slow during high-precision measurement, the error rate is high when decoding, and the anti-pollution ability is weak

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