On 12-Nov-2005, "Jay Honeck" wrote:

Yeah, my near-vision has gone completely to crap in the last few years.
I still don't wear bi-focals, but both my eye and medical doctors told
me that my days are, indeed, numbered.

I can't see diddly on a sectional anymore without holding it four
inches from my eyes. Can anyone recommend "progressive" bi-focals?
How about TRI-focals? Any benefit there?


I use bi-focal glasses with a straight horizontal division between the
"far" and "near" parts. This division is positioned rather high, just below
the point through which I look when looking straight ahead. In a plane it
more or less coincides with the upper edge of the glare shield, so when
looking at the instruments I use the "near" part.
I bought these glasses some years ago primary for my flying, but nowadays I
use it almost exclusively. For computer work only (staring at a monitor for
long periods) I have full vision reading glasses.
At the start it took some getting used to. In particular when turning your
head sideways the lower part of your field of vision seems to move relative
to the upper part. However I got used to it fast and nowadays I do not
notice it anymore.
The only drawback of these glasses is using it while riding a motor cycle.
This does not feel good, it seems in this case you use the lower part of
your field of vision for positioning. For this activity I have full vision
"far" seeing glasses.

Things I think are important:
- Use glass for better scratch resistance and a better quality of the
anti-reflection layer;
- The division between far- and near sight portion has to be perfectly
horizontal and be at the same position for both glasses;
- The optical center of the lenses has to coincide as perfectly as possible
with the center of your pupils.