An air sterilizer for eliminating an associated airborne contaminant from an associated volume of air is provided. The metal frame comprises a plurality of side walls and a notch is passed through at least one side wall. When these are steered in synchronism, it is possible to improve the overall gain of the array in any particular direction. The lens holding member causes at least one circumferential portion of the lens to protrude to the lens holder side, and causes the optical axis of the lens to match the optical axis of the illumination light. The base can be shaped to have a flat profile or to have a profile of a corporate logo when viewed side-on. In addition, the system includes inter-group links directly connecting each node in each node group to a node in each neighboring node group in the M dimensional grid.