Best lens material and optical designs for rimless frames

Hi everybody:

I have several related questions concerning different lens materials
and rimless mounts. I apologize for a long post but it seems to me
that many people can benefit from answers to my questions.

My prescription is:

D.V.
O.D.: Sph. -4.50, Cyl. -0.50, Axis 165
O.S.: Sph. -4.25, Cyl. -0.50, Axis 005

N.V.
O.D.: +0.50
O.S.: +0.50

Pupillary Distance: 64 mm

After many years of wearing big plastic frames I decide to switch to
the rimless kind. My new frame is a three-piece mount with screws -
each lens requires two holes and two notches. The dimensions of the
frame are 51x16.

I bought the frame in Europe and brought it to my current
optician/dispenser in L.A. for fitting. Upon seeing the frame he
commented that because of the notches there will be a surcharge ($50)
and the turnaround is going to be longer (about two weeks). I
understand that the lenses need to be sent to an actual lab for edging
etc., but am still surprised by this relatively long turnaround. The
place where I bought the frame offered to fit me with Hoya aspherics
either overnight (as a rush job) or within 3 days (as a regular job).
Unfortunately even that was too long for me because I had to return to
the States the same evening.

Anyhow, there are now couple of issues I'd appreciate some comments or
info about:

1. Which lens material to go for?
Because of the low risk of chipping my optician's assistant pushes for
polycarbonate which I don't like because of its low Abbe. I have
polycarbs in one of my glasses and cannot stand the chromatic
aberration. My optician thinks that we could safely order Pentax
UltraThin 1.67 (his default high index lenses), but is also willing to
order other brands if I wish. Unfortunately, Pentax UltraThin also has
a low Abbe of 32 so I am investigating other options. My first choice
would be SOLA Finalite 1.6 ( Abbe = 42) followed by HOYA EYAS 1.6
(Abbe = 41).
1. Can you please comment on these lens choices and their availability
in single vision (I don't care about correcting my tiny near vision
problems.)?
2. Should I expect to pay more for SOLA or HOYA compared to Pentax.
3. Is there any difference between these three lenses in terms of how
difficult they are to finish?
4. Can somebody calculate and compare the edge thickness for Pentax
vs. SOLA given my frame size?
5. Given my relatively small astigmatism, does it make any sense to go
for atoric designs like SOLA ViZio, and similarly, does it make any
sense to try to correct my small presbyopia either with separate
glasses or with bifocals/progressives?
6. Is there an easy way to identify the lens brand once the lenses
have been mounted?

2. Spherical or Aspherical design?
My background is in visual perception/optics so I know the advantages
of aspherical designs. I also know how important it is to fit the
aspherics correctly. However, my optician claims that even when their
glasses were fitted correctly many patients had hard time with the
transition from spherical to aspherical lenses.
1. Can somebody corroborate this or provide a personal testimonial?
2. How much thinner will my lens edge be if I opt for aspherics (which
I intend to)?

I would greatly appreciate any other comments and suggestions
regarding high index lens materials, aspherical designs and rimless
frames.

Thanks,

John

 

Thanks for warning me - I didn't realize that it was that difficult.
Somehow, I naively thought that some big fully automatic edger/drill
would simply make an identical copy of the demo lens. Now that you
made me worry, can you tell me what should I be looking for in the
final product to see if the job was done properly.

Finalite is/was my first choice but I wasn't aware that AO XT 16 is
using it, However, I got a bit confused by what I recently read at

http://www.visioncareproducts.com/19/lens_atoric.html

According to that article regular aspheric lenses cannot correct
astigmatism and only atorics can.

What is your take on that claim? What do you think about Sola Vizio
using high index (1.66) but low abbe material (abbe 32)? My personal
favorite would be Sola Vizio using Finalite but apparently Sola is not
offering that.

By the way do you know what is the center thickness of vizio in my
power and what would be the edge thicknes given the size of the
frame:

My prescription is:

D.V.
O.D.: Sph. -4.50, Cyl. -0.50, Axis 165
O.S.: Sph. -4.25, Cyl. -0.50, Axis 005

Pupillary Distance: 64 mm.
The dimensions of the frame are 51x16.

It indeed does. Thanks a lot.

-John

 

Robert and Jeff thanks a lot for your advice and for improving the S/N
ratio of this group.

-John