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We present a two-axis microelectromechanical systems (MEMS) lens aligner with a 260 μm × 220 μm translation range that positions a 6.35 mm lens with focal length f = 12.1 mm for alignment compensation of free-space optical interconnects (FSOIs) between computer servers separated by 50 mm spacing. Efficient ultrasonic linear piezoelectric motors (PMs) provide actuation with zero power required to hold the lens alignment. A four-channel FSOI is demonstrated with 1 × 4 vertical cavity surface-emitting laser (VCSEL) and photodiode (PD) arrays capable of 10 Gb/s transmission bandwidth. Demonstrated minimum step size of 1.68 μm is sufficient for aligning the 20 μm VCSEL spots onto the 40 μ m PD receivers. Force transmission between PMs and a silicon MEMS flexure stage is accomplished using a 1-mm steel ball bearing in a magnetic groove, providing compliance in the nondriven axis. The ball-coupling design has 15 μm backlash and induces a maximum of 8 μm of cross-axis motion.