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In order to quickly obtain the effect of different bonding process on the surface-shape of the adhesive bonded mirror, the simulation and experimental study of the linear expansion micro-stress assembly process were carried out.The mathematical expression of the solidification micro-stress of the adhesive in plane mirror assembly is derived based on the volume shrinkage rate. The structural stiffness of the mirror and the frame is also taken into the mathematical expression of the micro-stress.A finite element model named "Mirror-Adhesive -Frame" was developed using ANSYS Parametric Design Language (APDL) and User Interface Design Language (UIDL) to calculate the PV and RMS values of the surface-shape of the mirror after bonding.The ZYGO interferometer is used to measure the PV and RMS values of the surface-shape index before and after the bonding of the mirror with a specification of Φ100mm-15mm. By comparing the experimental results and the simulation results, the correction value of the equivalent linear expansion parameter of the adhesive layer is obtained. Then, the corrected equivalent linear expansion coefficient of the adhesive layer is brought into the simulation model to predict the PV and RMS values. The results show that the prediction results of the developed simulation model are in good agreement with the measurement results. Moreover, it is found that when the circumference and back of the mirror are both bonded, the PV and RMS values of the surface-shape reach the maximum, and the PV and RMS values are 0.187λ and 0.044λ, respectively
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