An Instrument For Displacement Measurement And Calibration With High Accuracy And Large Range

With the development of the science in application, nanometer measuring is the one of most parts in this fields, it apply more wide in measuring field. It was more needed urgently because of low cost and more convenient. Now the most of instruments for measuring and calibrating are designed by the technology of Heterodyne Interferometer, F-P, frequency scanning Interferometer etc, but they are more sensitive in normal lab surroundings, and they are complicated in structure and cost high, it is difficult to meet the need in the normal surroundings. So I design an instrument for displacement measurement and calibration with high accuracy and large range. it is designed by the principle of laser in common path polarize interference, low cost, simple in structure and good stabilization in application, be propitious to apply in normal surroundings.First, based on reading comprehensive and deeply concluding the literature in domestic and abroad, introducing the history and the trend of the high precision instruments for measuring in detail, thereout put forward the purpose of the project.Second, based on the principle of laser in common path polarize interference to design a compact high precision instrument for measuring and calibration in long displacement, introduce the system of work principle and characters, presentation the whole structure of instrument in detail, and introduce the function of all the subparts.Third, design the system of high precision measuring and calibration in long displacement, including polarizes interfering optic structure, photoelectricity detect circuit and signal magnify circuit, stripe counting and subdivision circuit.Fourth, construct a high precision apparatus for measuring and calibration in long displacement, complete the experiments, and draw a conclusion to certify the theory.