focal-
the
distances
From-
dioptric-
answer
of
power-
is
outcome
is
the
and
the
of-
the
effective
out
is.
between
The
inverse,
this
is
length
the
the
the-
this
of
add
new
vertex
The
carried-
and-
the.
difference-
value
length
lens
focal
the
inverse
result-
