Interchangeable low-backscatter aperture structure

摘要

An interchangeable low-backscatter aperture structure includes but is not limited to an aperture insert that is releasably engaged in a base. The aperture insert includes an aperture that may be of any shape. For example, the aperture may comprise a slit or it may be circular. The aperture insert may be held in the base by any securing mechanism capable of releasably securing the insert to the base. In one embodiment the securing mechanism includes a plurality of pressure clips.