What do they call this process...???

Is there a name of the process where an optician can figure out the
prescription of a pair of glasses?

Is this hard to do? Can any optician do it and most importantly, can
it be done with precision and accuracy?

Thanks in advance

LEESA (I)

Dear Leesa,

Subject: Methods of measurement.

Re: Using a Snellen and Trial-lens kit.

No, it is not difficult to determine the refractive STATE of the eye.

You simply need a trial-lens kit and a Snellen to do it.

The instrument used in an ODs office is an "enhanced" trial lens kit.

But the process is to find a lens that "sharpens" your vision to your
satisfaction.


Enjoy,



On Oct 25, 5:48*am, LEESA <taylorlee...@gmail.com> wrote:
> Is there a name of the process where an optician can figure out the
> prescription of a pair of glasses?
>
> Is this hard to do? *Can any optician do it and most importantly, can
> it be done with precision and accuracy?
>
> Thanks in advance
>
> LEESA *(I)

On Oct 25, 3:48*am, LEESA <taylorlee...@gmail.com> wrote:
> Is there a name of the process where an optician can figure out the
> prescription of a pair of glasses?

Neutralizing the lens

> Is this hard to do? *Can any optician do it and most importantly, can
> it be done with precision and accuracy?

It's pretty standard.

Just like checking tire pressures, though, it depends on an accurate
instrument, properly used. Also, the more complex the prescription,
the more margin of error.

http://www.opticiansfriend.com/main/...of-spectacles/

Dear Leesa,

The instrument is called a "Lenonometer" (Sp?)

You simply place the "un-known" lens in the instrument and
"neutralize" the lens.

With a "Spherical" lens the results are generally to 1/4 diopters.

With a more complex (Cyl.) the results are less accurate -- but can be
made.

Enjoy,



On Oct 25, 5:48*am, LEESA <taylorlee...@gmail.com> wrote:
> Is there a name of the process where an optician can figure out the
> prescription of a pair of glasses?
>
> Is this hard to do? *Can any optician do it and most importantly, can
> it be done with precision and accuracy?
>
> Thanks in advance
>
> LEESA *(I)

Here is a more detailed description of this Lensometer:


http://vision.about.com/od/eyeexamin...ensometer..htm


Enjoy,


On Oct 25, 11:08*am, Otis <otisbr...@embarqmail.com> wrote:
> Dear Leesa,
>
> The instrument is called a "Lenonometer" (Sp?)
>
> You simply place the "un-known" lens in the instrument and
> "neutralize" the lens.
>
> With a "Spherical" lens the results are generally to 1/4 diopters.
>
> With a more complex (Cyl.) the results are less accurate -- but can be
> made.
>
> Enjoy,
>
> On Oct 25, 5:48*am, LEESA <taylorlee...@gmail.com> wrote:
>
>
>
> > Is there a name of the process where an optician can figure out the
> > prescription of a pair of glasses?
>
> > Is this hard to do? *Can any optician do it and most importantly, can
> > it be done with precision and accuracy?
>
> > Thanks in advance
>
> > LEESA *(I)- Hide quoted text -
>
> - Show quoted text -

Mike,

I responded to LEESA's question.

Don't be stupid about this.

If LEESA did not like the answer -- it is up to HER to say so -- not
you.

I RESPECT her intelligence on this issue -- you obviously do not.

Second-opinion best,



On Oct 25, 11:27*am, "Mike Tyner" <mty...@mindspring.com> wrote:
> "Otis" <otisbr...@embarqmail.com> wrote
>
> > No, it is not difficult to determine the refractive STATE of the eye.
>
> See, it's reckless to answer every question, when you have no training or
> experience.
>
> You thought she asked about "refraction." She didn't.
>
> (You don't like to call it "refraction" because you don't have any training
> or experience.)
>
> She's asking about "neutralizing."
>
> (You won't like that term either because you have no training or
> experience).
>
> > You simply need a trial-lens kit and a Snellen to do it.
>
> Now, you don't know it but you've actually hit on the explanation for the
> term "neutralizing." It's because, before instruments like the B&L
> Lensometer, lenses were measured by matching them with known lenses of
> opposite power, such that the motion of magnification was "neutralized" when
> looking through the paired unit.
>
> I know I lost you, but it's really very simple.
>
> Say you have glasses that are -8.00, but we don't know the actual power.
>
> Say I have a trial set with +7.50, +8.00, and +8.50.
>
> One-by-one, I hold your -800 up, sandwiched against one of my high-plus
> lenses, and look through the combination at some distant object. When I move
> the paired lenses side-to-side, as a unit, the image I see through them will
> move also, because of magnification or minification, unless the lenses match
> exactly.
>
> If I sandwich your -800 with a +850, the combination has a value of +050 and
> there is positive magnification and excessive motion. *If I combine
> your -800 with a +750, there is a -050 net power that yields negative mag
> and _reduced_ motion. If I combine your -800 with a +800, there is NO
> motion, so we say the lenses are NEUTRALIZED.
>
> Instruments like the lensometer also "neutralize" but they change the power
> of the "neutralizing" lens rather than switching lenses.
>
> > The instrument used in an ODs office is an "enhanced" trial lens kit.
>
> That's for measuring EYES, not glasses.
>
> > But the process is to find a lens that "sharpens" your vision to
> > your satisfaction.
>
> That's another process. You don't have any training or experience with that,
> either.
>
> -MT

On Oct 25, 9:32*am, Otis <otisbr...@embarqmail.com> wrote:
> Mike,
>
> I responded to LEESA's question.

Nah. You just wrote whatever you felt like writing ... and
demonstrated beyond doubt that you had NO idea what she was asking.

> Don't be stupid about this.

Says s.m.v.'s resident absolute idiot.

More meds, Otis. It's time.

Oh.

Gee.

Otis deleted his original "reply." Shocked, I am. Don't worry,
Otis. Mike memorialized your stupidity for all to see.