Cross-scale Micro-nano Measurement Algorithm And Implementation Of Grating Based On Double A/D Sampling

This research is mainly about the grating cross-scale measurement.The algorithm and implementation method of the micro-nano measurement based on double A/D sampling are studied and the experimental verification is carried out.The proposed crossscale measurement algorithm brings out the advantages of different A/D chips.For example,it makes full use of the high-speed measurement characteristics of low-value A/D chips and the sampling characteristics of high-digital A/D chips for low-speed measurement.A cross-scale measurement system with high-speed measurement characteristics,micro-nano measurement resolution long stroke and micro-nano stroke is built.Through detailed experimental data,the feasibility and effectiveness of the crossscale grating micro-nano measurement algorithm with double A/D sampling are verified.The main research contents are as follows:(1)The principle,characteristics and scope of application with present different cross-scale displacement measurement method are analyzed,and the research status and development of grating in cross-scale measurement are introduced.(2)A cross-scale grating micro-nano measurement algorithm based on double A/D sampling is proposed.The key technologies are studies in depth,including on the doubleA/D sampling,grating subdivision,tracking algorithm and measurement algorithm of the cross-scale measurement algorithm,the time benchmark of the double A/D sampling and its impact on the cross-scale measurement.The feasibility of the cross-scale grating micro-nano measurement algorithm with double A/D sampling is verified from theoretical level.(3)The realization method of double-A/D sampling cross-scale grating micro-nano measurement algorithm is studied.The hardware system and software system are designed.The design of grating subdivision dynamic library and parameter design of for double A/D sampling tracking algorithm and measurement algorithm are discussed.A set of time difference extraction software for the time base of double A/D sampling is designed.This software provides a reliable method for obtaining experimental data and verifying the double-A/D sampling cross-scale grating micro-nano measurement algorithm.(4)A double-A/D sampling cross-scale grating micro-nano measurement system is constructed.Two A/D acquisition cards with different sampling parameters are selected,and various parameters of the measurement system are tested and verified.For example,the time difference extraction experiment of the start sequence and read sequence of the two different sampling parameter A/D acquisition cards,single measurement resolution acquisition experiment of double A/D sampling,tracking and measurement algorithm cross-scale micro-nano measurement experimental verification,etc.Furthermore,the effectiveness of cross-scale grating micro-nano measurement with double A/D sampling is verified in experimental level.