An apparatus having a plurality of arrayed MEMS devices, each device having a parallel-plate actuator and a reflective plate, both of which are mechanically coupled to a flexible beam attached between two anchors. Advantageously, the use of parallel-plate actuators in the apparatus alleviates stringent requirements for the alignment of lithographic masks employed in the fabrication process. In one embodiment, each flexible beam has a relatively small thickness and a relatively large length to effect a relatively large displacement range for the corresponding reflective plate. Movable electrodes of different parallel-plate actuators are configured to act as an electrical shield for the flexible beams, which reduces inter-device crosstalk in the apparatus. Reflective plates of different MEMS devices form a segmented mirror, which is suitable for adaptive-optics and/or maskless lithography applications.