Research On A Double Grating Interference Displacement Sensor

With the development of modern manufacturing, high precision measuring and displacement sensor is used more urgently which is low cost and convenient in normal experiment and production conditions.In this paper, a kind of displacement sensor based on the principle of double grating interference is introduced. Owing to the diffraction and interference, this displacement sensor has large measurement range, high accuracy, And because of double grating interference, it takes less room, is very steady, and has ability to resist environment noise. So it meets the need of high precision measuring in normal experiment and production conditions.First of all, double grating interference is researched deeply in this paper. And make out the principle of two gratings interference. Second, a double grating interference displacement sensor system is designed, and this system contents the mechanical system design and the signal processing circuit design. A experimental device is made. And it is made up of semiconductor laser, double grating interference cell, displacement guiding mechanism, photoelectric receiver, the signal processing circuit and so on. The design measurement range can reach 15mm, the resolving power can reach 0.01μm. Third, the analysis about system accuracy and factors such as mechanical factors, optical factors and electric factors which shall influence the accuracy is worked out.At last, testing experiment is carry out based on the experimental device. Initial experiment result proves that the system has a good accuracy character and stability, and could meet the need of high precision measuring in normal experiment and production conditions.