Research On The Relationship Between Measurement Accuracy And Electrical Error In Nanometer Time Grating

The large-scale nano-displacement measurement technology and devices are the core technologies and key functional components of precision high-end equipment such as nano-machine tools,defense and military,and are one of important indicator of the development level of precision manufacturing.However,the large range and high measurement accuracy has been a worldwide technical problem.Due to optical diffraction problems,the measurement principle and manufacturing of grating sensors occupying a high position in industrial applications are difficult to further improve.In addition,a few developed countries have mastered the relevant original ideas and core technologies,but have strictly blocked other countries.In China,the grating sensor is mainly in the tracking research work,the technical level is always backward,the high-end grating sensor relies heavily on imports.For this reason,a third generation electric field time grating sensor based on capacitance array structure and using alternating to construct the uniform motion reference system is proposed by the author’s research group.By using the time grating measurement technology to solve the problem that the resolution is restricted by the gate spacing,using the flat capacitance structure as the sensing unit can reduce the manufacturing accuracy requirements,and rely on the advanced micro-fabrication technology of the grating to realize the high efficiency production.Based on this background,this article carried out an in-depth study of the electrical errors of nanoscale time-grating sensors.The main research contents and innovations are as follows:1)The measurement principle of the nanometer time grating sensor is modeled,and the model of the chip lead impedance,distributed capacitance and amplifier input resistor circuit is established.Based on the knowledge of the circuit,the mathematical expression of the electrical error based on the complex number algorithm is calculated.2)The relationship between the electrical errors produced by the lead impedance,the distributed capacitance,the input impedance of the amplifier and the measurement accuracy is analyzed emphatically.Through the simulation,the best lead impedance,distributed capacitance,and input impedance value of the amplifier are found under the condition of ensuring the minimum electrical error.3)Optimize sensor structure and parameters,further reduce electrical errors and improve measurement accuracy.In the manufacture of the sensor,the geometry of the sensor is optimized,the area of the capacitor is adjusted,the working capacitance is increased,and the accuracy of the sensor is improved.Change the capacitance value by changing the gap of the moving ruler,reduce the nonlinear component in the coupled signal,reduce the nonlinear error,and improve the sensor accuracy.The time difference measurement link optimizes the measurement circuit and uses multiple comparison techniques in the signal processing and shaping circuit to make the integral square wave information of the sinusoidal signal sensed by the moving rule more complete and improve the accuracy of the sensor.Finally,according to the time measurement space,the idea design experiment using the time signal to compensate for the spatial signal is also used to compensate for the third electrical error and further improve the measurement accuracy.A set of parameters optimization design criteria for nanometer time grating sensors has been formed,laying a foundation for the development of high precision nanometer time grating sensors.4)The Super Precision experimental platform is built and the sensor prototype is made.The measurement accuracy and stability of the sensor were tested to verify the correctness of the theoretical analysis.Finally,a prototype of a nanometer time-grating sensor with a measuring range of 200 mm and a measurement accuracy of ? 200 nm was developed,and it has excellent anti-interference ability,stability,installation flexibility and lower manufacturing costs.In summary,through the combination of theory and practice,this paper finally establishes the nanoscale time-grating electrical error theory system and parameter optimization design method,the proposed structure and parameters of the optimization design of the nanoscale time-grating parameters to improve the measurement accuracy of a certain guiding significance...