A shutter for controlling radiation exposure includes a rotatable member. The rotatable member is rotatable between an open position and a closed position. The rotatable member includes a passageway, wherein the passageway is positioned to receive radiation in the open position and is not positioned to receive radiation in the closed position. In the closed position, the rotatable member may substantially block or absorb the radiation. The passageway may collimate the radiation into a beam of radiation. The rotatable member may include a plurality of passageways positioned to receive radiation in the open position. The rotatable member may be rotatable between a plurality of open positions, each open position corresponding to at least one passageway. The open positions may align the source of radiation with different passageways in the rotatable member to form a different beam shape, a different number of beams, a different beam direction, or combinations thereof.