Freeviewer's Assistant formally the 
One
Eye Stereoscope
This is a one-eye stereoscope. It works by using a set of front surface
mirrors to
superimpose the left image onto the right for easy viewing. It takes a
little time to master but the results are well worth it. It can be used on
any variety of side by side (Parallel
def) formats as well as being the one of the only viewers of its type that
can view an over/under (Viewmagic
type) stereoview (to view over/under use the viewer like a periscope). It
also is used for cross eyed
viewing. Being a mirrored lensless viewer it has no focal length so it
can be used for any size image. It also comes with a an opening cover for
protection of the optical element.
You
can get an adjustable headstrap for long term or
hands free use. To use it for over/under pairs simply orientate it in the
vertical position. Use without the headstrap for a portable viewer that
will fit in your pocket or purse!
