Modeling anamorphic optical surfaces in the MOEMS-based zoom lens

MOEMS (Micro-opto-electromechanical systems) based zoom lens is a kind of optical system combining the off-axis reflective DM (deformable mirrors) and the on-axis refractive elements. It usually has two deformable mirrors. The magnification of one DM would be variable while its surface profile is changed by controlling the actuators, which results in a focal shift in the image space of the zoom lens. To compensate the variation of the focal plane position, the surface profile of another DM is varied. Therefore the focal length of the whole optical system would be varied and have a stabilized image position. In this paper, modeling anamorphic optical surfaces in the MOEMS-based zoom lens is described. The anamorphic profile of the DM is designed to satisfy the following requirements. First, the aberration coefficients of the DMs and the refractive surfaces are composed in the vector space to achieve the coefficients of the system. And the initial configuration of the refractive elements is determined to fulfill the system requirements and specifications at the wide angle and long focal length positions. Then the anamorphic profile of the DM is designed to compensate the off axis aberrations by creating two zeros of low order astigmatism, achieved a reasonable result.