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  1. Just to confuse the issue a little more it is...

    Just to confuse the issue a little more it is Silver Halide in photochromic glass. This was a offshoot of a defense dept project to instantly darken the window on a bomber after an atomic blast to...
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    Blended lenticulars were available in round segs...

    Blended lenticulars were available in round segs emphasize were. When telling someone to turn the glasses around for an accurate reading you should be more specific. You turn them around to find the...
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    A lenticular can be a single vision or a bifocal...

    A lenticular can be a single vision or a bifocal in round style or ft22. If you look at her old lenses you can see the the seg if it is there. With a high Rx like I doubt she could wear a...
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    There are some metal frames that are screw less...

    There are some metal frames that are screw less but the lenses that are used are not standard lens material they are very thin and flexible and do not meet the impact resistance required in some...
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    Glare from headlights has been a complaint since...

    Glare from headlights has been a complaint since cars were invented. The problem was completely solved in 1930’s by Dr Land of the Polaroid Land Camera company. He placed a polarizing filter(which he...
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    I assume you are talking about edge polishing. It...

    I assume you are talking about edge polishing. It surely can be done but I don’t recommend it the reflection caused by the thickness will be extremely annoying to the patient. If you have access to a...
  7. Thread: Trivex

    by Lensman11
    Replies
    56
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    14,760

    Poly will not crack or split during mounting as I...

    Poly will not crack or split during mounting as I stated it might stress crack at a latter date due to poor techniques used during mounting. The question was does Trivex weigh more or less than Poly...
  8. Thread: Trivex

    by Lensman11
    Replies
    56
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    14,760

    The weight will always be the same. There is no...

    The weight will always be the same. There is no reason to make Trivex thicker than poly due to the mounting requirements both materials resist splitting and cracking equally. When a comparison is...
  9. Thread: Trivex

    by Lensman11
    Replies
    56
    Views
    14,760

    Poly became the material of choice when drill...

    Poly became the material of choice when drill mounts were the rage. Cr had to be made thicker for drill mounting and had a teddency to crack at the drill points. Poly solved both of these problems...
  10. If I understand what you are doing you are moving...

    If I understand what you are doing you are moving a +3.00 two different amounts and correctly get two different amounts of prism. This has nothing to do with thickness only the fact that the larger...
  11. A Plano prism is not controlled by thickness but...

    A Plano prism is not controlled by thickness but by prism angle or by not having parallel surfaces but that does not come into play in this case as the segment is optically centered and contains no...
  12. The size of the seg or the thickness of the seg...

    The size of the seg or the thickness of the seg will not alter the prismatic effect it is a function of the power. We used to have more problems of this type when executive type lenses were popular....
  13. Thread: Pen for AR

    by Lensman11
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    This is only one that I ever found that works...

    This is only one that I ever found that works 100% of the time. Staedtler permanant specialLumocolor. Black
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    You can calculate the answer not at an...

    You can calculate the answer not at an engineering level. Poly is 10% thinner than Trivex and 10% heavier so the end result is they will way the same.
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    Tintable hard coats are less scratch resistant...

    Tintable hard coats are less scratch resistant therefore not the best choice for AR. It is possible to tint a lens before it is hard coated but if you dip coat your hard coating will become...
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    Progressive surface on the front Toric surface on...

    Progressive surface on the front Toric surface on the back yields a combination of the two that that the patient looks thru. In a freeform design that combination is created on the back of the lens....
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    50 years in the lab never have seen this one. It...

    50 years in the lab never have seen this one. It might be a dental plier ask your dentist you might be surprised.
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    Added point of information the gain in thickness...

    Added point of information the gain in thickness for poly only applies to minus power lenses and that is because you gain 0.7 mm thickness reduction because the center thickness on poly and all high...
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    Discussions usually work best. You gain 25% when...

    Discussions usually work best. You gain 25% when you go from cr to poly and a weight reduction. Each index past Poly will yield a about a 10% thickness reduction for each increase in index but no...
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    You could get a design patent which covers the...

    You could get a design patent which covers the appearance of an object but a slight modification would go around your patent. Remember a patent only gives you the right to go to court to defend it....
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    Try searching under Executive bifocals as that...

    Try searching under Executive bifocals as that was the branded name. Also search on the history of American Optical as they invented the one piece Executive lens. The Franklin was actually two...
  22. You can have an aspheric Toric concave surface...

    You can have an aspheric Toric concave surface put on a standard ft
  23. What do you want to compensate?

    What do you want to compensate?
  24. Yes they do you can probably find one on EBay

    Yes they do you can probably find one on EBay
  25. Try to get a Nikon projection lensometer.

    Try to get a Nikon projection lensometer.
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