A miniaturized adaptive-focus camera objective featuring a gravity-immune liquid-tunable aspherical lens is presented. The lens, which has an aperture size of 3 mm, a nominal focal length of 8mm and an optimum tuning range between 7.2 to 8.8 mm, is experimentally demonstrated to have diffraction-limited performance at the nominal focal length with identical performance for vertical and horizontal lens orientations, leading to a drastic reduction in spherical aberration compared to conventional liquid-tunable lenses. The camera objective comprises three fixed elements and a tunable lens, arranged on a 5×5×13 mm platform. It provides a viewing angle of 40° imaged on a 3 mm sensor. By tuning the lens in its optimum operation range, the object distance can be shifted from 5mm to infinity.
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