The Habitable Exoplanet Imaging Mission (HabEx) is a NASA flagship mission to be considered for the 2020 Decadal Survey in Astronomy and Astrophysics. The concept is to develop an imaging system to detail the characteristics of planetary systems surrounding solar-type stars. The system must provide high contrast imaging and spectroscopy with a high signal-to-noise ratio and high stability. In this paper, we will present a point design for a 4 meter, off-axis, monolithic primary mirror to be used in the HabEx imaging system. An initial optimization of design parameters was performed to minimize distortions due to vibration while also maintaining a low areal density. Finite Element Models (FEM) of mirrors were created with varying mounting configurations, materials, depths, rib thicknesses, cell sizes, facesheet thicknesses, and depths. A harmonic analysis was performed on each model, and the corresponding displacements were output from the optical surface. The data from each model was imported into MATLAB and the distortion on the optical surface of each model was analyzed. Thus, the optimal design parameters were chosen based on the vibration performance of each design. The analysis and the chosen point design will be discussed further throughout the paper.
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