Finite-element-method study of the effect of thin-film residual stresses on high-order aberrations of deformable mirrors

摘要

To analyze the influence of the thin-film residual stresses on the high-order aberrations of deformable mirrors, a finite-element model of a 37-element deformable mirror was constructed. The deformation and high-order aberrations were simulated after applying residual stresses to the mirrors. The appearance of high-order aberrations became more significant as the mirror thickness decreased. A print-through effect due to the piezoelectric actuators was obvious when the mirror thickness was 1 mm. The peak-to-valley size decreased from 0.320 to 0.158 mu m when the mirror thickness increased from 1 to 3 mm, and the corresponding residual error after removing the low-order Zernike coefficients decreased from 0.281 to 0.156 mu m. High-order aberrations of the deformed mirrors were very small at a mirror thickness of 3 mm. These results should be useful for designing deformable mirrors for adaptive optical systems in the future.