bi-ocular devices

[P3D Peter Abrahams <telscope@xxxxxxxxxx>]

>"Because of my long abiding interest in 3-D...I have fitted 
>these...large diopters...optical apertures in my dwelling." 
I once hurled a computer through a similar optical aperture, but the
resultant carnage was outlawed from exhibition at a stereo show because it
came through the viewing window.
It is always good to be reminded that one doesn't need fancy equipment to
enjoy stereoscopic vision.
However, the original notion of using a large magnifying glass as an
enhancer of stereoscopy has some merit.  By allowing the binocular viewing
of a very close object, exaggerated convergence enhances the perception of
depth by allowing the viewer to see 'two sides' of the object.  It does
require a large chunk of glass to achieve some diopters in a lens of
interpupillary diameter.
Bi-ocular devices (2 eyes, one lens system) were by coincidence the subject
of today's post on postcard viewers and makeup mirrors.  I don't recall
other discussion of these systems, probably due to their limited use and my
limited memory.    Are there stereoscopic applications of bi-ocular optics?

\\\\\\\\\\\\\\\///////////////
Peter Abrahams, telscope@xxxxxxxxxx
the history of the telescope, the microscope
     and the prism binocular


------------------------------