An optical system includes a primary lens group having a central beam path
therethrough and including a front lens group and a rear lens group. An
anamorphic lens group lies on the central beam path and is positioned
between the front lens group and the rear lens group. The anamorphic lens
group includes at least one optically powered anamorphic lens that has
different enlargements of a light beam along different axes perpendicular
to the central beam path. The anamorphic lens group may be mounted on
structure that allows it to be removed from the central beam path. An
image transceiver is either an image source that directs a light beam
through the primary lens group and the anamorphic lens group, or is an
image receiver that receives a light beam through the primary lens group
and the anamorphic lens group.