In this paper, we have produced a lens using PDMS flexible, we studied the mechanical properties of the lens. Measuring the shape of the lens as a result after deformation of the base membrane, and calculate change of radius of curvature. Also, the finite element analysis. Cylindrical supporting post of the lens is present, it was possible to significantly reduce the change of the lens. The experimental conditions of this study, when the length of the post is less than 4 mm, change of the lens occurs in proportion to the deformation of the base membrane. However, the lens did not affect the change when the length of the post is at least 4 mm, even to deform the base membrane. When designing a flexible lens, considering the length of the post, it will be a hint to prevent change of the lens.