The high price and optical complexity of the marketable optical devices
used for indirect ophthalmoscopy can be overcome by the use of
the fixed binocular visualization unit with or without the erecting optical
system.
These devices can thence be made much simpler, very efficient, easier
to master with minimum maintenance cost.
Consequently these devices can be made available to all the doctors
at low cost.
Thus a proper health care of patient can be more easily achieved mainly
in the developing countries.