Page 2 of 2 FirstFirst 12
Results 26 to 36 of 36

Thread: I think Zeiss is now in a very good position for a change.

  1. #26
    Compulsive Truthteller OptiBoard Gold Supporter Uncle Fester's Avatar
    Join Date
    Dec 2004
    Location
    At a position without dimension...
    Occupation
    Dispensing Optician
    Posts
    4,512
    The smoke continues to flow from my ears and obscures the room.

    Can you dumb this down for the mathematically challenged?

  2. #27
    Master OptiBoarder lensgrinder's Avatar
    Join Date
    Jul 2005
    Location
    Raleigh, NC
    Occupation
    Lens Manufacturer
    Posts
    484
    Quote Originally Posted by Uncle Fester View Post
    The smoke continues to flow from my ears and obscures the room.


    Can you dumb this down for the mathematically challenged?



    In order for a lens to be free from astigmatic blur at all gaze angles light should come to a point focus on the far point sphere(center of rotation - focal length of the lens). This imaginary sphere is used as a reference point. If light focuses behind or in front of the sphere the lens will not be clear. You may have experienced this when a wearer looks in the periphery and states it is not as clear as it is in the center.
    Dr Marius Tscherning discovered that two forms exist where a lens will be free from astigmatism(each one of these forms had been previously discovered independently by Ostwalt and Wallaston). For example a -5.00 that is 2 mm thick with a 27 mm center of rotation in CR-39 should be placed on either a 16.73 D BC or a 4.64 D BC. If you change the power to -4.75, this changes the two base curves to 16.84 D and 4.78 D. Based on Tscherning's work the ZIESS Punktal and AO's Tillyer lens were created.
    Corrected curve theory is based on Tscherning's ellipse. Corrected curve theory groups powers that will have a certain amount of astigmatism in a series of base curves.
    As our focus changes the far point sphere becomes the near point sphere, which will require a new form to be free from astigmatism.
    FFSV lenses corrects the astigmatism for each gaze angle in the distance portion, however, in the past they did not correct the astigmatism produced at near.


    I hope this helps.

  3. #28
    OptiBoard Apprentice Lawman Nick's Avatar
    Join Date
    Jan 2020
    Location
    Oklahoma
    Occupation
    Dispensing Optician
    Posts
    31
    *edit*

    nevermind, question answered. Please delete
    Last edited by Lawman Nick; 06-22-2020 at 03:16 PM. Reason: I'm a big ol' bonehead

  4. #29
    Compulsive Truthteller OptiBoard Gold Supporter Uncle Fester's Avatar
    Join Date
    Dec 2004
    Location
    At a position without dimension...
    Occupation
    Dispensing Optician
    Posts
    4,512
    Thanks- this did help with a second closer reading of drk's always erudite posts.

    If this came to me easily I very much doubt I would be an optician.

    I still get nervous selling something that seems to fix for most what isn't broken. or seemingly they didn't know it was broken until I'm selling it.

    Too often I fear the what if- such as when a patient gets switched to the latest and greatest and expects immediate results only to return later asking for a redo (and worse, refund) for the more expensive lenses.

    So I often qualify the change with a proverbial "your results may vary".

    With the right patient who doesn't like the change I've even lightened the mood with a "Who are you going to believe? The optical engineers or your own d*amn eyes!"

  5. #30
    Master OptiBoarder AngeHamm's Avatar
    Join Date
    Apr 2010
    Location
    Richmond, VA
    Occupation
    Optical Retail
    Posts
    2,059
    Quote Originally Posted by Uncle Fester View Post
    Too often I fear the what if- such as when a patient gets switched to the latest and greatest and expects immediate results only to return later asking for a redo (and worse, refund) for the more expensive lenses.
    I'll take "Varilux S Design" for a thousand, Alex.
    I'm Andrew Hamm and I approve this message.

  6. #31
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    7,887
    OK, I'm learning.

    The most basic model of Zeiss' new "Lite" basic model series has a 14 and 18mm variation.

    14 is corridor length, I think. Ergo, for a minimum recommended fitting height for this variation, add, what? 4-5 mm? So, it's good for 18-19 mm fitting heights?

    Or is 14 the minimum recommended fitting height, itself?

    Same with 18. It could be for 22-23 mm fitting heights, or it could be the minimum recommended fitting height.

    I need some smart dude to set me straight.

  7. #32
    OptiBoard Professional
    Join Date
    Jan 2017
    Location
    USA
    Occupation
    Dispensing Optician
    Posts
    105
    Quote Originally Posted by drk View Post
    OK, I'm learning.

    The most basic model of Zeiss' new "Lite" basic model series has a 14 and 18mm variation.

    14 is corridor length, I think. Ergo, for a minimum recommended fitting height for this variation, add, what? 4-5 mm? So, it's good for 18-19 mm fitting heights?

    Or is 14 the minimum recommended fitting height, itself?

    Same with 18. It could be for 22-23 mm fitting heights, or it could be the minimum recommended fitting height.

    I need some smart dude to set me straight.
    I've always added 4 to the minimum fitting height so people dont complain about the near zone being too low.

    The Zeiss Lite lenses come in three flavors.

    The D is the lowest tier with 14,18 corridors and "optimized boundaries for widest fields of view"
    The H comes in 14, 16, and 18 with optimized boundaries and "binocular optimization"
    The V is a variable corridor for customized fitting heights as low as 13mm.

    The intermediate and Near Zones are supposed to be a few mm wider than average but the distance zone seems pretty narrow with a good amount of distortion in the periphery. I'm not sure if thats due to "Binocular optimization" or not trying to put all the bells and whistles in a lower priced lens.

    Now Zeiss has the Smartlife "Pure" in Small, Medium, and Large to replace the Precision Pure. I have no idea what lengths Small, Medium and Large refer to and the only thing the lab could tell me was that its the same as the Precision Pure which comes in 13, 15, 17, 19, 21 lengths. I have not been able to find any centration charts or other documentation explaining how to fit small, medium, and large which is pretty unhelpful on zeiss' part.

  8. #33
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    7,887
    Thanks, Alex.

    Have you sampled the Lite lenses? Or have had patients react?

  9. #34
    Master OptiBoarder lensgrinder's Avatar
    Join Date
    Jul 2005
    Location
    Raleigh, NC
    Occupation
    Lens Manufacturer
    Posts
    484
    OK, I'm learning. The most basic model of Zeiss' new "Lite" basic model series has a 14 and 18mm variation.14 is corridor length, I think. Ergo, for a minimum recommended fitting height for this variation, add, what? 4-5 mm? So, it's good for 18-19 mm fitting heights?Or is 14 the minimum recommended fitting height, itself?Same with 18. It could be for 22-23 mm fitting heights, or it could be the minimum recommended fitting height.I need some smart dude to set me straight.
    The Light D has two fitting height options, 18 mm and 14 mm (Light D 18 and Light D 14), these are the minimum fitting height. The corridor length for the 14 is ~10 mm and the 18 is ~14 mm. The Light H has three fitting heights 14, 16, 18 (Light H 14, Light H 16, Light H 18), each of those numbers are the minimum fitting height and the corridor length for the Light H 16 is ~12 mm.
    I've always added 4 to the minimum fitting height so people dont complain about the near zone being too low. The intermediate and Near Zones are supposed to be a few mm wider than average but the distance zone seems pretty narrow with a good amount of distortion in the periphery. I'm not sure if thats due to "Binocular optimization" or not trying to put all the bells and whistles in a lower priced lens.
    A Light D/H 14 has a 10 mm corridor length, this is pretty short so the wearer should be able to get into he near quite fast. Adding 4 mm potentially places the wearer near the intermediate portion which will definitely cause blur. This is not something we commonly hear.
    Now Zeiss has the Smartlife "Pure" in Small, Medium, and Large to replace the Precision Pure. I have no idea what lengths Small, Medium and Large refer to and the only thing the lab could tell me was that its the same as the Precision Pure which comes in 13, 15, 17, 19, 21 lengths. I have not been able to find any centration charts or other documentation explaining how to fit small, medium, and large which is pretty unhelpful on zeiss' part.
    I will be happy to send you centration charts if you send me your email address, mine is Brent.mccardle@zeiss.comThe Pure S is a 14 mm minimum height the Pure M is 16 mm and the Pure L is 18 mm.

  10. #35
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    7,887
    Excellent info Grinder!

  11. #36
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    7,887
    Ok, new question for Brent or other geniuses.

    I'm going to make a couple of sweeping generalizations.

    1. The Zeiss Individual has become the Zeiss Pure/Superb (depending on whether it's fixed or variable, respectively). It is a balanced design.
    2. The Zeiss Individual 2 has become the Zeiss Smartlife Individual, which comes in "Balanced" (T-shaped), "Intermediate" (V-shaped) or "Near" (hourglass).

    Now, as to the subtle differences between the Smartlife Individual B and the Zeiss Pure/Superb, I will leave you to fill that in. It will be a small difference, I'm guessing.



    Now, on to the "Light" portfolio, and my main questions.

    The Light is roughly organized into good-better-best based on two features: one, corridor type
    a. variable corridor
    b. fixed corridor 3 choices
    c. fixed corridor 2 choices

    and the other differentiating feature is "binocular optimization". What is that, really? Designing the lenses as a pair, and trying to match zone widths regardless of distance portion powers?


    And here's my big, big question about the Light portfolio: I know they're digitally surfaced, and obviously you can input corridor length, but are these lenses optimized by lens power (atoric curves)? And what is the intended design? Is it a "softer" low-astigmatism approach? It seems like it.




    Also, in general, what is "digital inside"? It's described as helping near devices and reading. I understand what we were saying earlier about the Tscherning ellipse for SV near optimization. Is this just the analogue for PALs? Or, is it a corridor modification?
    Last edited by drk; 07-14-2020 at 06:31 PM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Replies: 0
    Last Post: 07-23-2012, 10:14 AM
  2. Replies: 0
    Last Post: 03-25-2009, 01:58 PM
  3. US position on Climate change
    By QDO1 in forum Just Conversation
    Replies: 0
    Last Post: 12-03-2005, 04:52 AM
  4. The good doctor's position
    By mrba in forum Just Conversation
    Replies: 0
    Last Post: 04-06-2004, 12:09 PM
  5. whats a good carrer change for a fed up Optician
    By Bill in forum General Optics and Eyecare Discussion Forum
    Replies: 7
    Last Post: 03-16-2002, 12:51 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
OptiBoard is proudly sponsored by:
Younger Optics and Vision Equipment