An optical switch has an array of fibers, an optional lens, and a mirror with two-dimensional tilt adjustment. Light from the array passes through the lens, is reflected by the mirror, and passes again through the lens back towards the array. The input/output fibers are arranged in a two-dimensional pattern designed to avoid undesirable crosstalk between fibers. The pattern may include a plurality of fibers positioned around a central fiber in a circular arrangement. For a 18 or 81 switch, nine fibers are preferably positioned in a circle around the central fiber, thereby providing geometry that substantially avoids undesirable crosstalk between fibers in the array. In another implementation, the fiber array is implemented using a tapered ferrule housing a central fiber, surrounded by an intermediate layer of six fibers, surrounded by an outer layer of twelve fibers.