Problem with No-Line Bifocals

I'm unhappy with my no-line bifocals. This is only my second
prescription for glasses and I didn't have this problem with the first
set. I'm going to get new glasses and I want to avoid this problem in
the future.

The problem is when I'm reading the edges of my vision aren't quite in
focus. It's quite annoying. For example if I view a group of words in
the middle of a page they are clearly seen but the words along the
margins of a page aren't quite clear.

My prescripition is as follows:

Spherical: OD -0.75 OS -1.00
Cylinderical: Sph Sph
Add: OD +1.75 OS +1.75

My lens size is 54 mm width and 38 mm height. Nothing special about
the lenses, just the usual thickness CR 39.

When I first got the glasses I complained about this. I had my
eyeglasses checked for accuracy against the prescription and they
matched up. I had my eyes re-examined and my doctor recommended that
the store re-measure my PD, which they did, and found that it was the
same as they had measured the first time.

What causes the problem I am encountering? How can I avoid it with my
new prescription?

Also, what determines the height of the near-vision portion of the
lens? For example, my lens is 38 mm high, so where does the reading
portion of the lens start? Is it at the halfway point? Can I specify
this to be smaller or larger if I desire?

Thanks for your help.

 

I think I'm on my third pair of no-lines.

I'm not a professional, but as a wearer I think you can't avoid it. It's
the nature of the beast. These glasses are the typical jack of all trades,
master of none. I find the reading/distance problem gets worse as my eyes
ages.

I had to get single vision glasses to use with my desktop computer because
no-lines were utterly, totally useless for that task. I'm considering
reading glasses for the times I want to do some serious reading. For the
transitory every day tasks no-lines are OK.

They had a very scientific method in my case. I wore a pair of dummy
glasses and looked at a distant object in the mall. They marked the
position on the lens with a black marker!

I'm sure they can vary the position... but how many experiments can one
afford? The only way to check is to make a pair, and as we know they're not
cheap.

 

How about "executive" bifocals -- line straight across the middle.

Have the top be for computer distance, and bottom for reading --
thus you work on the screen, then switch to your notes at desk
level in front of you.

Works for me!

David

 

Hello,

problem is no-line.

Lena

 

All designs is bad, they are is full of astigmatic distortion

For optician the best to sell no-line
The cost of production of no-lines maximum 50 $ sell prise 400$
Cost of singles almost the same sell price 140$

Regards

 

David, I agree
In spite of some distortions at the line
The exec are much healthy for eyes.

No-line (progressives) shut -off accommodation at all.

Lena

 

They do?

So ... can you tell me where you get your data showing that presbyopes
have perfectly accurate accommodative responses?

Thanks.

 

Sorry. Rishi Giovanni Gatti (Zetsu) and Otis Brown are
long-time trolls who haunt s.m.v.

Lena102938 aspires to troll status based primarily upon her
constant use of anti-eye doctor rhetoric as a
substitute for any actual information.

You'd do well to ignore them and wait for
responses from the caring, compassionate eye doctors who
DO also participate in this site.

 

Presbyopes do not have accurate accommodative response, as you know .
Moreover , this knowledge is in perfect correlation with the opinion
of her majesty ,science.

But what is left from accommodation progressives switch off.

 

I guess you know the meaning of a non-sequitur, huh?

 

Her mind works in mysterious ways.

 

this is your personal opinion. you can either choose a progressive or
a lined bifocal so simply choose the one that you prefer and quit
stating your personal opinions to everyone else as if they are facts.
they are not!

this is true if you look off-center. it is not true if you look
straight ahead.
once again your knowledge and understanding is limited yet you act as
though you are an expert on the subject.

where ever you are buying your glasses, I would look elsewhere.
sometimes there is a slightly higher price for no-lines versus lines
but not at all like what you are saying.

do you think you exaggerate sometimes?

 

lena102938 is a typical USENET troll/kook who espouses typical
troll/kook conspiracy theories (i.e. all peer reviewed research on the
subject is incorrect because of a conspiracy amongst university research
professors to increase profits in the optometry business). Peer-reviewed
research says that accomodation changes occur because of aging, not
because of the type of glasses that you wear. Please ignore.

- Elron

 

Why would you say this? It simply isn't true.

 

As others have noted, by and large this is the nature of the beast.
Unfortunately many dispensing optometrists are not aware of the
limitations of what they're selling their customers and do not provide
proper warning. Progressives are good for tasks that require focusing
upon a single point, such as working on an automobile or sewing a
garment, but are not good for tasks that require a field of vision such
as working on a computer, and some people simply can't tolerate them
because of the blur at the edges of vision causing nausea and/or
headaches. The other option is the lined type of bifocal, which has a
slight blur at the transition but otherwise provides a clear field of
vision in the top part or bottom part of the lens. If your optometrist
and optician cannot find a progressive lens that will work for you, that
is the most likely solution that you'll end up with.

-Elron

 

The off-axis blur is common to all of the progressives, but some
designs are able to minimize it. I use mine for the computer and have
no issues. The field of view is adequate for all except the most
demanding of occupations involving a wide field at near.

 

Mike,accommodation , close to 0, am i right ?

But if at least 2D left, why not make the eyes to perform some job,
just a little ?

 

Hi,

Actually, that is not the only truth.

The truth is, all glasses 'suck', anywhere you are at the time.
How can you be so stupid as to continue wearing them, when you know of
their uselessness? Begin the rest methods and see what you have been
missing for all these years.

 

If you make anything not to work it is
not going to work.
Restrict hand movement. Weak mascule will be weaker.

At 55 + please -progressives.

At 40 ? It is a lot of accommodation left.

It is like that : who been with OD has progressives,
who have not been perfectly wears Reading glasses only for Reading.

Show me at lest a few who visited OD at 40 and did not got
progressives ?

PS: I know theory that lens grows , becomes less elastic, etc.
And ciliary muscle in vitro contracts under pilocarpine, which leads
to conclusion that it is in perfect shape.

 

if even 2D left and add +1 it is not a brick wall

autonomic sphincter.does not make it any better.
It only means that it shuts off accommodation on
neurological level .

Is it any other examples of mass disfunction of any other autonomic
sphincters at 40 ?