Research On Key Technology Of Phase Shifter Of Fizeau Interferometer

Interference measurement technology is a new type of measurement technology. It is based on the principle of optical interference, and the wavelength of light is as the unit of measurement. It has many advantages, such as large range, high sensitivity, high accuracy, etc. it is widely used in the field of optical processing and testing. With the appearance of laser technology and its application in optical measurement field, the resolution, accuracy, anti-interference ability and stability of the interference measurement technology have significant progress. Fizeau interferometer is an interferometer developed according to the Interference principle of light. In the early stage, the interference measurement technique was used to analyze the static interference pattern, and the center of the fringe was need to be determined, which led to low efficiency and low accuracy. So the phase shift interferometry(PSI) is gradually developed. Phase shift is a key component of phase-shifting Fizeau interferometer to realize the purpose of the phase shifting. It is a one dimensional micro displacement device with a high resolution, and has a high requirement for resolution and linearity.To solve the above problems, this paper conducts an investigation on the current situation of domestic and foreign micro displacement mechanism, analyses the advantages and disadvantages of different structures, and finally chooses a structure form, which is actuated by piezoelectric ceramic actuator, transmitted by flexure hinge. Finally, theoretical analysis, simulation and test of phase shifter is completed.The main work of this thesis is as follows:1. Structure design of the phase shifterThe structure form of phase shifter which is actuated by piezoelectric ceramic actuator, transmitted by flexure hinge is chose after an investigation on the current situation of domestic and foreign micro displacement mechanism. And through the analysis of the technical index, the model of the piezoelectric ceramic actuator and the form of the flexure hinge are determined. A new type of reversing flexible hinge is designed, and the structure of the whole phase shifter is designed.2. Test of piezoelectric ceramic actuatorPiezoelectric ceramic has the disadvantages of hysteresis, creep and nonlinearity, so it is necessary to carry out the relevant test of the piezoelectric ceramic actuator.3. Theoretical analysis, simulation and test of flexible hingeIn this paper, a new type of reversing flexure hinge is designed. The theoretical analysis, finite element simulation and test are carried out for the reversing flexure hinge, and the three results are compared. The relative error between theoretical values and simulation values of the stiffness and the transmission ratio of the reversing flexure hinge is-3.31% and 5.27% respectively. The relative errors between theoretical values and experimental values of the stiffness and the transmission ratio of the reversing flexure hinge are within 6% and 11% respectively.4. Theoretical analysis, simulation and test of phase shifterTheoretical analysis, finite element simulation and test of the designed phase shifter are carried out, and the phase shifter is corrected. A three-way test platform of phase shifter is designed because the phase shifter is three-way driven. The displacement curve tested by the three-way test platform is corrected by adjust driving voltage. The final displacement curve’ linearity is fine, and residual error is within 23 nm.