Abstract: Presented is a method, apparatus, and computer-readable medium for selectively switching optical paths. The apparatus includes a directing mirror for redirecting light from an incoming path to one of a plurality of input paths and redirecting the light from one of a plurality of output paths to an outgoing path, and a plurality of input mirrors, each one of the plurality of input mirrors operable for redirecting the light from one of the plurality of input paths to one of a plurality of transition paths. The apparatus includes a plurality of light modifying elements, each one of the light modifying elements in a corresponding transition path and a plurality of output mirrors, each one of the plurality of output mirrors operable for redirecting the light from one of the plurality of transition paths to one of a plurality of output paths.

Abstract: Presented is a method, apparatus and computer-readable medium for reducing error. The apparatus includes a rotatable element having a plurality of spaced light modifying ports located at set positions in the rotatable element, the rotatable element rotatable about an axis. The apparatus further includes a drive engagedly coupled to the rotatable element to rotate the rotatable element, wherein one periodic cycle of the rotatable element is an integer number of periodic cycles of the drive.