Are we getting carried away?

[OCP]

Pete you got a hard job and will always be in crossfire because of this.
Actually, I have a challenging job- which is what makes it fun, and frustrating at times. :)
Seriously, my grandfather (who grew up in the Great Depression- so he had a pronounced appreciation of steady employment) gave me a little sign that hung on his cubicle (he worked as a Warrant Officer in the Pentagon for a number of years) that says "Thank God for the Troubles in Your Job." The main message being, if it weren't for the challenges of your particular job, ANYONE could be found to do the job at half of what they're probably paying you- so be thankful for challenges, because they pretty much account for your salary. Let's just say that- over the 7 years I've been working for Essilor, I've had several opportunities to be thankful!

Anyone professional and clever eye doctor and optician, knows that pupil size dosen't matter when talking about glasses. Contact lenses is a different question.
If you had said "the higher order aberrations within the eye do not matter when talking about glasses" you would have been mostly correct- because while you can resolve some higher order aberrations within the eye with a contact lens, an eyeglass lens cannot be used to resolve higher order aberrations within the eye. I say mostly because Zeiss is currently taking the impact of higher order aberrations within the eye into account when filling a lower order Rx. Also, technically speaking, if you can tolerate them I would imagine the best form of ophthalmic correction possible is found in a rigid gas permeable lens (which resolves irregularities on the cornea with a tear lens).

Regarding pupil size, however... From an optics perspective- pupil size has greater impact on the performance of an eyeglass lens than on a contact lens. I am not an expert in contact lenses, but as I recall the size of the pupil plays a role in determining the proper geometry of the CL (i.e., larger pupils require contact lenses with a larger diameter- either diameter of zone or physical diameter.

There are several reasons why this is true, but the first lies in the vertex distance between the lens stop (pupil) and the lens in question. In a contact lens, the vertex is pretty small- a CL sits about 3mm in front of the pupil iris (as I recall the anterior chamber is about 3mm deep- correct me if I'm mistaken). An eyeglass lens sits about 15mm in front of the iris.

The relevance of all this is seen when we ray trace light "backwards" from the retina out the front of the eye. Since a lens focuses light on the retina, we will see the light diverging as it leaves the retina towards the lens stop. The light making it through the aperature is still diverging, and in 3mm it will meet the cornea where we can measure its diameter. In another 12mm or so our rays will meet the back of the eyeglass lens- where it will form a larger diameter.

As the diameter becomes larger, it becomes harder to control the optics. To illustrate, we all know that anyone (with otherwise healthy eyes) will have 20/20 vision looking through a pinhole- regardless of refraction (because only one ray of light travels through the pinhole, and it is unrefracted). As the hole is increased in size, a greater column of rays passes through the lens stop- and any aberrations in the system become more apparent. Therefore, if an eyeglass lens has aberrations, those aberrations will become more apparent (at a faster rate than with contact lenses due to the relative vertices) as the pupil size increases.

In the distance portion of the lens, Varilux Physio is designed to control (eliminate or greatly reduce) higher order aberrations across a diameter on the lens that corresponds to a 6mm pupil size. In Varilux Physio Enhanced, higher order aberrations are controlled for an 8mm pupil size. Assuming this control actually occurs, we would expect individuals wearing the two lenses to notice sharper vision in low light conditions (and in fact wearers do significantly prefer Varilux Physio Enhanced over Varilux Physio in dim lighting conditions (p=<0.01).

Hi Pete

I fully agree with challenges. Without challenges I would personal be bored to death.

Back to pupil size. I agree a normal persons vision will be better/sharper with smaller pupil size, thats what we call the pinhole effect. But how in the whole world can you use this knowledge to anything in a fixed lens design?
-unless you make the pinhole effect in your lens, as I don´t think you do.

Because the pupil size are not an fixed value you cant take this into account in a fixed lens design.

What is default pupil size? 6 mm?
Can you make an better lens design if the pupil size is 4 or 8 mm?
If you actually could do that, why don´t you just use that specific design for all pupil sizes.?

I see other more important issues in a progressive lens design, such as handling of abberations, lower astigmatic deviation and better handling of the aspherical design.

But this is so boring parameters and I think the design teams are to much focused on more hyped trivial features to get the attention from the opticians around the world.

Mike

[YrahG]

Hi Pete

I fully agree with challenges. Without challenges I would personal be bored to death.

Back to pupil size. I agree a normal persons vision will be better/sharper with smaller pupil size, thats what we call the pinhole effect. But how in the whole world can you use this knowledge to anything in a fixed lens design?
-unless you make the pinhole effect in your lens, as I don´t think you do.

Because the pupil size are not an fixed value you cant take this into account in a fixed lens design.

What is default pupil size? 6 mm?
Can you make an better lens design if the pupil size is 4 or 8 mm?
If you actually could do that, why don´t you just use that specific design for all pupil sizes.?

I see other more important issues in a progressive lens design, such as handling of abberations, lower astigmatic deviation and better handling of the aspherical design.

But this is so boring parameters and I think the design teams are to much focused on more hyped trivial features to get the attention from the opticians around the world.

Mike

The pupil size has an effect on the spherical aberration and coma present, however to reduce these two aberrations the cost is less emphasis on other aberrations such as marginal astigmatism and distortion. Every manufacturer has their own so called recipe as to which aberrations are more important then others. You like Coke, but that doesn't make it better than Pepsi, if we can come to an understanding that people are as individual in their viewing tasks and preferences as they are in their taste for soft drinks then it becomes evident that their really cannot be a one great PAL lens but a portfolio of offereings that all complement each other. This can help an office offer an eyewear experience that is unparalleled.

[scriptfiller]

Pete,

Are the optics in the Physio enhanced optimized (better corrected) for larger pupil diameters. I know from the photographic industry that lenses with f ratios less than 3 the optics in the lense have to be made to higher standards due to the fact that a larger more corrected lenses are needed to transmit the added light to the photosite without vignetting, coma and CA. An F/2.8 lense will allow more light than an F/3.5 lense.

[Pete Hanlin]

Unfortunately, I won't have as much time this week to respond to this thread. However, I've tried to put together two images in an attempt to quickly explain the role of pupil size...

In an optical system, the size of the lens stop is connected to the perception of aberrations. In fact, this is why coma is usually not a significant issue (because the size of the pupil minimizes the impact of coma). However, many PALs have significantly more coma around the PRP/FRP due to the changing curvature of the lens surface.

Again, if the pupil is small the issue is minimized. However, in distance viewing (and in dim lighting) the pupil dilates- which increases the area of the lens being used (and therefore the impact of any aberrations present in the system).

The first graphic attached illustrates the perception of the wavefront at different pupil sizes. When the pupil is small, the impact will be minimal (if the pupil constricted to a pinhole, the impact of any aberrations in the system would be completely removed). As the pupil dilates (either due to dim light or by looking in the distance), aberrations in the lens have a larger impact on the wavefront perceived by the eye.

When this happens, the MTF value of the lens is reduced (the image produced by the lens has less contrast than the object being viewed). The result is a reduction in contrast perception (and perceived image sharpness).

The second graphic illustrates some concepts we haven't even touched on- namely the alignment of astigmatism in the immediate intermediate periphery and the control of power in the near. The alignment of astigmatism in the intermediate periphery will impact the perception of width (assuming you do not require cylinder, try putting 0.50D of cyl in each eye of the phoropter... place both axes at 90, and I bet the results aren't very disturbing to your vision- now try placing the axes at opposing diagonals... a bit more disturbing).

There are two concepts that differentiate Varilux Physio Enhanced from the original Varilux Physio. First, in the distance the wavefront is controlled out to a diameter of 8mm vs. 6mm. Second, the "pattern" of wavefront correction (the mapping of the pupil sizes controlled) is changed from lens to lens to best suit the patient's Rx, approximate age, visual distance, and the worst anticipated lighting condition in each zone.

"Why not just control to 8mm everywhere?" is a legitimate question. Higher order aberrations are somewhat similar to lower order aberrations (astigmatism), in that you can't totally eliminate them- at best you can control them more in specific areas than others. In short, Varilux Physio Enhanced has a "multi-design" approach to how higher order aberrations are controlled. BTW, control of higher and lower order aberrations are not mutually exclusive (you can do both at the same time). However, both have to exist- you can't just totally eliminate both.

Not much time to go back and edit this post- lots to do today. Hopefully, however, this answers some of the questions regarding the impact of pupil size on vision in a PAL.

[Pete Hanlin]

Oh, and by the way- as YrahG suggested, I have an awesome (if sometimes challenging) job. If you've ever watched Working Girl, the conclusion of the movie sums up quite well how I feel about my job (cue the "Let the River Flow" music- although my hair isn't quite as "big" as Melanie Griffith's :)). Each day I get to think about what concepts/products we'd like to test (I would have KILLED to have this ability when I was still dispensing).

In fact, that's what I have to go do now- work on summarizing some data from a study...

[OCP]

Unfortunately, I won't have as much time this week to respond to this thread. However, I've tried to put together two images in an attempt to quickly explain the role of pupil size...

In an optical system, the size of the lens stop is connected to the perception of aberrations. In fact, this is why coma is usually not a significant issue (because the size of the pupil minimizes the impact of coma). However, many PALs have significantly more coma around the PRP/FRP due to the changing curvature of the lens surface.

Again, if the pupil is small the issue is minimized. However, in distance viewing (and in dim lighting) the pupil dilates- which increases the area of the lens being used (and therefore the impact of any aberrations present in the system).

The first graphic attached illustrates the perception of the wavefront at different pupil sizes. When the pupil is small, the impact will be minimal (if the pupil constricted to a pinhole, the impact of any aberrations in the system would be completely removed). As the pupil dilates (either due to dim light or by looking in the distance), aberrations in the lens have a larger impact on the wavefront perceived by the eye.

When this happens, the MTF value of the lens is reduced (the image produced by the lens has less contrast than the object being viewed). The result is a reduction in contrast perception (and perceived image sharpness).

The second graphic illustrates some concepts we haven't even touched on- namely the alignment of astigmatism in the immediate intermediate periphery and the control of power in the near. The alignment of astigmatism in the intermediate periphery will impact the perception of width (assuming you do not require cylinder, try putting 0.50D of cyl in each eye of the phoropter... place both axes at 90, and I bet the results aren't very disturbing to your vision- now try placing the axes at opposing diagonals... a bit more disturbing).

There are two concepts that differentiate Varilux Physio Enhanced from the original Varilux Physio. First, in the distance the wavefront is controlled out to a diameter of 8mm vs. 6mm. Second, the "pattern" of wavefront correction (the mapping of the pupil sizes controlled) is changed from lens to lens to best suit the patient's Rx, approximate age, visual distance, and the worst anticipated lighting condition in each zone.

"Why not just control to 8mm everywhere?" is a legitimate question. Higher order aberrations are somewhat similar to lower order aberrations (astigmatism), in that you can't totally eliminate them- at best you can control them more in specific areas than others. In short, Varilux Physio Enhanced has a "multi-design" approach to how higher order aberrations are controlled. BTW, control of higher and lower order aberrations are not mutually exclusive (you can do both at the same time). However, both have to exist- you can't just totally eliminate both.

Not much time to go back and edit this post- lots to do today. Hopefully, however, this answers some of the questions regarding the impact of pupil size on vision in a PAL.

Hi Pete

Thanks for details concerning Pupil size.
I need to ask you. How and under which lighting conditions do you measure the pupil size?
Does this lens work only for people with chronic reduced pupil effect?

Normal pupil size goes from 3-6,5 mm in size in a day. Will this lens be delivered with an automatically battery function to change the design?

-I´m not kidding.


Mike

[YrahG]

Hi Pete

Thanks for details concerning Pupil size.
I need to ask you. How and under which lighting conditions do you measure the pupil size?
Does this lens work only for people with chronic reduced pupil effect?

Normal pupil size goes from 3-6,5 mm in size in a day. Will this lens be delivered with an automatically battery function to change the design?

-I´m not kidding.


Mike

The distance is designed for the worst case scenario with an 8mm pupil size, howver due to the constriction of the pupil during up close viewing task, the constriction and reduction in range of pupil size due to age, and otehr factors that effect the pupil size the intermediate and the near zones are optimized to smaller pupil diameters which allows Varilux to move some of that aberration control to other more important aberrations in those particular zones. I think the idea is interesting, I have been successful with the Physio products and see it as a significant step above the Comfort and Panamic. I just can't help but to feel that it could be better on the back side, luckily that will be available in the 3rd quarter this year.

Oh, and by the way- as YrahG suggested, I have an awesome (if sometimes challenging) job. If you've ever watched Working Girl, the conclusion of the movie sums up quite well how I feel about my job

I have never seen "Working Girl", but it made me laugh thinking that you feel like the conclusion to a movie called "Working Girl". Please don't post any pictures.:D Ok now I'm giving you a hard time.....j/k

[Pete Hanlin]

I need to ask you. How and under which lighting conditions do you measure the pupil size? Does this lens work only for people with chronic reduced pupil effect? Normal pupil size goes from 3-6,5 mm in size in a day. Will this lens be delivered with an automatically battery function to change the design?
No measurement of the individual's pupil size is required. Each Varilux Physio Enhanced lens controls the wavefront to various pupil diameters (ranging from around 8mm to 4mm) in a pattern that is determined by several factors:
Age- As the eye ages, the pupil size decreases slightly. The approximate age is taken from the ADD power (since ADD and age roughly correlate).
Rx- Due to refractive effects, the "effective pupil size" of a hyperope is larger than that of a myope. Even though a myope and hyperope may have the same size pupil, the area of the lens being viewed is larger for a hyperope- I think this was discussed earlier in the thread.
Viewing Distance- The pupil constricts when viewing near objects. Based on the power at each point in the lens, the focal length can be converted into the viewing distance, which can be used to determine the largest pupil size likely to exist when using a specific location on the lens.
Lighting Condition- Of course the lens doesn't know what lighting condition it is in at any given moment- but there are some assumptions that can be made regarding the worst likely lighting conditions the wearer will encounter at each viewing distance. In distance vision, the worst condition is likely to be quite dark (thus the worst case assumption of 8mm in the distance). In near vision, the worst condition is likely to be dim light (people can't/don't read in darkness- thus the 4mm at near).

Pupil sizes vary from one person to another- however, by knowing the person's age and Rx the "map" of the pupil sizes the patient is likely to have at different points in the lens can be moved around to a pattern most likely to correspond to the patient. The differences between Varilux Physio and Varilux Physio Enhanced are a.) there is "better" correction of the wavefront in Enhanced (larger diameters are controlled), and b.) greater attention is placed to the likely pupil size of each wearer at each location in the lens.

Keep in mind a.) if the controlled area is larger than the patient's actual pupil size- that's fine (being over isn't a problem), and b.) even if you have a patient with abnormally large pupils, Varilux Physio Enhanced still has better wavefront control than any other lens available (so there aren't any other lenses out there that are going to provide a "cleaner" wavefront to the patient). The goal of all this wavefront stuff is to provide sharper vision in all lighting conditions and all distances. I've posted another pic to explain the difference in approach between Varilux Physio and Varilux Physio Enhanced. The contours of the pupil size on the Varilux Physio Enhanced will change somewhat depending on the factors listed above.

Yesterday, I was summarizing the results of a study that was completed a week or so ago. In the study, the overall performance of Varilux Physio Enhanced lenses was compared to Varilux Physio lenses. Although a poster on the results will be available shortly, the study had three interesting findings:
1.) In "standard lighting" (100 cd/m2), 71% of the subjects who had a preference preferred Varilux Physio Enhanced.
2.) In "dim lighting" (25 cd/m2), the preference for Varilux Physio Enhanced was significant (p=0.006).
3.) In the subject comments, the most frequent comment was "these are sharper/clearer/more focused" (the wearer doesn't know which lens is which- but that's how they described the Varilux Physio Enhanced lenses).

THAT'S why I'm confident WAVE Technology 2 works... Given the main feature of the design is wavefront control, the fact that the preference increases in dim light (when the pupil is larger and the eye is more likely to notice wavefront aberrations) correlates with the MTF measurements that have been made on the lenses, and confirms that a practitioner should have good success with Varilux Physio Enhanced in real life. In particular, for people who complain about their vision in dim light (which is, I recall, a significant % of patients) Varilux Physio Enhanced lenses should be a good solution.

[OCP]

I need to ask you. How and under which lighting conditions do you measure the pupil size? Does this lens work only for people with chronic reduced pupil effect? Normal pupil size goes from 3-6,5 mm in size in a day. Will this lens be delivered with an automatically battery function to change the design?
No measurement of the individual's pupil size is required. Each Varilux Physio Enhanced lens controls the wavefront to various pupil diameters (ranging from around 8mm to 4mm) in a pattern that is determined by several factors:
Age- As the eye ages, the pupil size decreases slightly. The approximate age is taken from the ADD power (since ADD and age roughly correlate).
Rx- Due to refractive effects, the "effective pupil size" of a hyperope is larger than that of a myope. Even though a myope and hyperope may have the same size pupil, the area of the lens being viewed is larger for a hyperope- I think this was discussed earlier in the thread.
Viewing Distance- The pupil constricts when viewing near objects. Based on the power at each point in the lens, the focal length can be converted into the viewing distance, which can be used to determine the largest pupil size likely to exist when using a specific location on the lens.
Lighting Condition- Of course the lens doesn't know what lighting condition it is in at any given moment- but there are some assumptions that can be made regarding the worst likely lighting conditions the wearer will encounter at each viewing distance. In distance vision, the worst condition is likely to be quite dark (thus the worst case assumption of 8mm in the distance). In near vision, the worst condition is likely to be dim light (people can't/don't read in darkness- thus the 4mm at near).

Pupil sizes vary from one person to another- however, by knowing the person's age and Rx the "map" of the pupil sizes the patient is likely to have at different points in the lens can be moved around to a pattern most likely to correspond to the patient. The differences between Varilux Physio and Varilux Physio Enhanced are a.) there is "better" correction of the wavefront in Enhanced (larger diameters are controlled), and b.) greater attention is placed to the likely pupil size of each wearer at each location in the lens.

Keep in mind a.) if the controlled area is larger than the patient's actual pupil size- that's fine (being over isn't a problem), and b.) even if you have a patient with abnormally large pupils, Varilux Physio Enhanced still has better wavefront control than any other lens available (so there aren't any other lenses out there that are going to provide a "cleaner" wavefront to the patient). The goal of all this wavefront stuff is to provide sharper vision in all lighting conditions and all distances. I've posted another pic to explain the difference in approach between Varilux Physio and Varilux Physio Enhanced. The contours of the pupil size on the Varilux Physio Enhanced will change somewhat depending on the factors listed above.

Yesterday, I was summarizing the results of a study that was completed a week or so ago. In the study, the overall performance of Varilux Physio Enhanced lenses was compared to Varilux Physio lenses. Although a poster on the results will be available shortly, the study had three interesting findings:
1.) In "standard lighting" (100 cd/m2), 71% of the subjects who had a preference preferred Varilux Physio Enhanced.
2.) In "dim lighting" (25 cd/m2), the preference for Varilux Physio Enhanced was significant (p=0.006).
3.) In the subject comments, the most frequent comment was "these are sharper/clearer/more focused" (the wearer doesn't know which lens is which- but that's how they described the Varilux Physio Enhanced lenses).

THAT'S why I'm confident WAVE Technology 2 works... Given the main feature of the design is wavefront control, the fact that the preference increases in dim light (when the pupil is larger and the eye is more likely to notice wavefront aberrations) correlates with the MTF measurements that have been made on the lenses, and confirms that a practitioner should have good success with Varilux Physio Enhanced in real life. In particular, for people who complain about their vision in dim light (which is, I recall, a significant % of patients) Varilux Physio Enhanced lenses should be a good solution.

Pete I understand you quite well, but don´t believe the higher satisfaction level was according to the pupil size.
In my humble opinion, it´s because of an upgraded Physio design in general.
Shamir, and others, could make the same study between the Autograph Classic and the Autograph II and claim something like the lens are taking into account the depth of the eyeball and thats the reason that more clients prefer this lens. I don´t claim you personal, I just have my doubts that taking the pupil size into account in a lens, could have anything to do with the improved vision. That is simple not logic and realistic. In my world, it´s another fabricated story to sell a new (and maybe improved) lens.

Annoying Mike :shiner:

[Pete Hanlin]

Please don't post any pictures.:D
Okay, so you just know I have to post a picture... ;)
Tess McGill- the humble secretary who became a financial analyst on Wall Street!


Welcome to the 1980s! It was a good decade to own stock in hairspray manufacturing!

[YrahG]

I don´t claim you personal, I just have my doubts that the pupil size could have anything to do with the improved vision. That is simple not logic and realistic. In my world, it´s another fabricated story to sell a new (and maybe improved) lens.

Annoying Mike :shiner:

You may need to hit the books as everything said in Pete's post you referenced is fairly accurate and very logical.

[YrahG]

Please don't post any pictures.:D
Okay, so you just know I have to post a picture... ;)
Tess McGill- the humble secretary who became a financial analyst on Wall Street!


Welcome to the 1980s! It was a good decade to own stock in hairspray manufacturing!

That clears up a lot, I was thinking more the "Pretty Woman" type working girl. ;):p:D

[OCP]

You may need to hit the books as everything said in Pete's post you referenced is fairly accurate and very logical.

I did already read my books again, and still dont find anything that could justify this claim.
-and it´s not logical, it sounds good (the design teams are usual great to fabricate these stories) but it´s absolutely not logical and realistic at all.
Sorry.

I will look more and try to find any evidence that could prove your claims. -I don´t think anyone can find this hidden treasure that don´t exist.

Mike

[HarryChiling]

Thank you Pete and others for this lively discussion, helps to seperate the fluff from the stuff.

[YrahG]

I did already read my books again, and still dont find anything that could justify this claim.
-and it´s not logical, it sounds good (the design teams are usual great to fabricate these stories) but it´s absolutely not logical and realistic at all.
Sorry.

I will look more and try to find any evidence that could prove your claims. -I don´t think anyone can find this hidden treasure that don´t exist.

Mike

They are not claims, those points truly were facts.

Attached you will find excerpts from books in my library that discuss these concepts.

1. 1st image discusses the pupil range and how anything larger than 5mm may see reduced acuity due to spherical aberration.
2. 2nd image talks abotu the effects of illuminace on the constriction of the pupil.
3. 3rd image references smaller pupil diameters as a result of age.
4. 4th image defines spherical aberration and uses the term aperature which in our optical system is the pupil.
5. 5th image defines coma and uses the term aperature which in our optical system is the pupil.

I only used two book that I knew had references off the top of my head, but I could pull more if necessary. It is hard enough trying to get to the facts please verify your facts before posting them I am trying to have a serious discussion on the subject.

[OCP]

They are not claims, those points truly were facts.

Attached you will find excerpts from books in my library that discuss these concepts.

1. 1st image discusses the pupil range and how anything larger than 5mm may see reduced acuity due to spherical aberration.
2. 2nd image talks abotu the effects of illuminace on the constriction of the pupil.
3. 3rd image references smaller pupil diameters as a result of age.
4. 4th image defines spherical aberration and uses the term aperature which in our optical system is the pupil.
5. 5th image defines coma and uses the term aperature which in our optical system is the pupil.

I only used two book that I knew had references off the top of my head, but I could pull more if necessary. It is hard enough trying to get to the facts please verify your facts before posting them I am trying to have a serious discussion on the subject.

Ohh my good.
This is not what I am talking about, and you should know that.
No one here can argue against these fact that most of us learned 25 years ago, and I have never tried to do so, but you still need to tell me how you can use this anatomy knowledge in a optical lens.!
These facts is okay in a medical perspective, but you still need to convince me, and 10.000 others, how in heaven this can be used in a fixed lens design.

Mike

[YrahG]

These facts is okay in a medical perspective, but you still need to convince me, and 10.000 others, how in heaven this can be used in a fixed lens design.

Mike

The only thing I need to do is die and that is also a function of age.:D

I just have my doubts that taking the pupil size into account in a lens, could have anything to do with the improved vision. That is simple not logic and realistic. In my world, it´s another fabricated story to sell a new (and maybe improved) lens.

That is a direct quote of yours, I showed you more than anything I hope.

Pete I understand you quite well, but don´t believe the higher satisfaction level was according to the pupil size.

If that is the only thing changed in the design, then either it is the reason or they got a particularly frisky bunch in their testing.

This is not what I am talking about, and you should know that.
No one here can argue against these fact that most of us learned 25 years ago..........................................These facts is okay in a medical perspective, but you still need to convince me, and 10.000 others, how in heaven this can be used in a fixed lens design.

Before I go into explanation of how this factors in please let me know if this rudimetry explanation will insult your inteligence, because this too is in books that I could quote?

[OCP]

The only thing I need to do is die and that is also a function of age.:D



That is a direct quote of yours, I showed you more than anything I hope.



If that is the only thing changed in the design, then either it is the reason or they got a particularly frisky bunch in their testing.



Before I go into explanation of how this factors in please let me know if this rudimetry explanation will insult your inteligence, because this too is in books that I could quote?

Okay, but ones again. How can you use a variable value as the pupil size in a fixed lens design?
Under which light conditions will you measure the pupil.?
Do you know if the client works in white clinic or in a coal mine? Do you know if the client is a night worker or a day worker? I´m sure this will make an influence of the size of the pupil in a daily basis?
If the design will be better in a given pupil size, then it will be worse in another pupil size.
etc, etc.

My point is that this is absolutely meaningless.

Mike

[YrahG]

Okay, but ones again. How can you use a variable value as the pupil size in a fixed lens design?
Under which light conditions will you measure the pupil.?
Do you know if the client works in white clinic or in a coal mine? Do you know if the client is a night worker or a day worker? I´m sure this will make an influence of the size of the pupil in a daily basis?
If the design will be better in a given pupil size, then it will be worse in another pupil size.
etc, etc.

My point is that this is absolutely meaningless.

Mike

The pupil size is fixed for each zone but the size varies depending upon the zone. Although their is no way of predicting the amount of light that a person is going to be subjected to their are ways of guestimateing the data.

For instance one that has already been addresses is the age. If you told me an add power I am confident that I would be able to guess the persons age 90% of the time or better within +-3 years.

I can make an assumption that the lighting in an office will be 30 to 50 footcandles. Using the Advanced Energy Design Guide http://resourcecenter.pnl.gov/cocoon.../article//1427
using this data and additional research can prove to be beneficial in estimating a pupil size optimal for the reading zone.

The Rx is supplied by the ECP so no need to guess at that, plus dependeing on base curve you can guestimate a range of Rx's in the design since the design is on the front surface.

Viewing distance doesn't need to be estimated since we know the distance should be optimized for 20ft and the near zone should be optimized for 14 to 16 inches leaving everything between as a function of the add power.

Now keep in mind this is my quick estimation of these variables and it is inresponse to a post, imagine what could be done with vast resources and scientists available to refine these variables. I don't question at all that this is the reason fro the improvement of the design. I do however question the degree of benefit from these improvements.

The 30% claim on Varilux Physio is related to the design (specific comparison is to Varilux Panamic) and has been demonstrated on actual wearers.

I think it was telling that the 30% claim of wider zones was in comparison to the Panamic which is being discontinued. I don't think a reference to an irrelivant design is a good claim.

[Mr.Powers]

"If you told me an add power I am confident that I would be able to guess the persons age 90%"

i hav a Client whit Add : 2.50 ...............Guess his Age you can..... young Padawan.

Ofcoars you cant he can be from 60-100 years old but the degreasing of the pupil dont stop at 60 years so it is ones again BS from the Lens Manufactors.


best regards

Peter

[OCP]

The pupil size is fixed for each zone but the size varies depending upon the zone. Although their is no way of predicting the amount of light that a person is going to be subjected to their are ways of guestimateing the data.

For instance one that has already been addresses is the age. If you told me an add power I am confident that I would be able to guess the persons age 90% of the time or better within +-3 years.

I can make an assumption that the lighting in an office will be 30 to 50 footcandles. Using the Advanced Energy Design Guide http://resourcecenter.pnl.gov/cocoon.../article//1427
using this data and additional research can prove to be beneficial in estimating a pupil size optimal for the reading zone.

The Rx is supplied by the ECP so no need to guess at that, plus dependeing on base curve you can guestimate a range of Rx's in the design since the design is on the front surface.

Viewing distance doesn't need to be estimated since we know the distance should be optimized for 20ft and the near zone should be optimized for 14 to 16 inches leaving everything between as a function of the add power.

Now keep in mind this is my quick estimation of these variables and it is inresponse to a post, imagine what could be done with vast resources and scientists available to refine these variables. I don't question at all that this is the reason fro the improvement of the design. I do however question the degree of benefit from these improvements.



I think it was telling that the 30% claim of wider zones was in comparison to the Panamic which is being discontinued. I don't think a reference to an irrelivant design is a good claim.

I agree that you can asume some data if you know the age of the client, or the addition.
But you can only asume these things, and we are talking about FACTS.
You are on very thin ice here to claim that you/Essilor can make an individual and improved lens, only by measuring the size of the pupil.

How many in this forum does actually think that measuring the pupil size will noticeable improve the vision? We are talking about peripheral abberations in the cornea in a ultra super small amount, that is only measurable with laser equipment in dark light (or other high end equipment). Please anyone ask question.

Mike

[YrahG]

"If you told me an add power I am confident that I would be able to guess the persons age 90%"

i hav a Client whit Add : 2.50 ...............Guess his Age you can..... young Padawan.

Ofcoars you cant he can be from 60-100 years old but the degreasing of the pupil dont stop at 60 years so it is ones again BS from the Lens Manufactors.


best regards

Peter

Your right but if I was looking for the largest pupil size as the worst case scenario it wouldn't matter if the pupil continued to decrease or not. Their literature does mention the largest size aperature as 8mm and the smallest as 2mm, so either way the smallest diamter used will be 2mm.

I agree that you can asume some data if you know the age of the client, or the addition.
But you can only asume these things, and we are talking about FACTS.
You are on very thin ice here to claim that you/Essilor can make an individual and improved lens, only by measuring the size of the pupil.

I did not say individual, I did say improved. Matter of fact if you have been reading my posts I am very skeptical of the lens being called customized, apparently the definition of customized may have been changed to suit Essilors needs.

How many in this forum does actually think that measuring the pupil size will noticeable improve the vision?

I don't question at all that this is the reason fro the improvement of the design. I do however question the degree of benefit from these improvements.

1. power error
2. marginal astigmatism
3. distortion
4. spherical aberration
5. coma

Of the seidel aberrations I would rank them in the order above as to their importance. The pupil size is small enough that spherical aberration and coma are negligable similar to your example on the benefits from the potential accuracy gain from 0.06D rounding to 0.01D rounding (again notice I said potential).

I agree with you here and have from the beginning, I don't know if this will make a noticeable improvement or not. I have also ranked the aberrations in the order I see as the most beneficial. I am not interested in anyones opinions I am interested in facts. Many of the facts were laid out in this thread so it has served it's purpose, statements like the following:

so it is ones again BS from the Lens Manufactors.

There is a lot of BS in this industry if your just now realizing it welcome to the world. Consider this your competitor and you both think you are the best, one of you is BS'ing.

But you can only asume these things, and we are talking about FACTS.

Well then we will never get anywhere since this is optical theory we are dealing with and fromt eh start we are making assumptions that our understanding of optics is a fact.

Shamir, and others, could make the same study between the Autograph Classic and the Autograph II and claim something like the lens are taking into account the depth of the eyeball and thats the reason that more clients prefer this lens.

You seem to have an axe to grind. I get it you like Shamir over Essilor. I agree but also think that my clients deserve the best available so it is my responsibility to learn the facts about all available designs BEFORE making my decision which lens will best suit the pateints needs.

To do that I need to listen and learn, I was trying to provide some insight into how the lens might work, but it seems you are not interested so I will just quite down and lurk instead of participate until the next new lens design comes out.

[OCP]

Your right but if I was looking for the largest pupil size as the worst case scenario it wouldn't matter if the pupil continued to decrease or not. Their literature does mention the largest size aperature as 8mm and the smallest as 2mm, so either way the smallest diamter used will be 2mm.



I did not say individual, I did say improved. Matter of fact if you have been reading my posts I am very skeptical of the lens being called customized, apparently the definition of customized may have been changed to suit Essilors needs.








I agree with you here and have from the beginning, I don't know if this will make a noticeable improvement or not. I have also ranked the aberrations in the order I see as the most beneficial. I am not interested in anyones opinions I am interested in facts. Many of the facts were laid out in this thread so it has served it's purpose, statements like the following:



There is a lot of BS in this industry if your just now realizing it welcome to the world. Consider this your competitor and you both think you are the best, one of you is BS'ing.



Well then we will never get anywhere since this is optical theory we are dealing with and fromt eh start we are making assumptions that our understanding of optics is a fact.



You seem to have an axe to grind. I get it you like Shamir over Essilor. I agree but also think that my clients deserve the best available so it is my responsibility to learn the facts about all available designs BEFORE making my decision which lens will best suit the pateints needs.

To do that I need to listen and learn, I was trying to provide some insight into how the lens might work, but it seems you are not interested so I will just quite down and lurk instead of participate until the next new lens design comes out.

Okay, I will try to put this down on paper.
What we are talking about here (just to make sure everyone and my self understand prober) is the distortion the Cornea create in the peripheral part of cornea (that is aprox. 2 mm from the center). In the theory it can be possible to compensate for the distortion in the lens IF THE PERSON IS ALLWAYS LOOKING STRAIHGT AHEAD, AND IF YOU KNOW HOW THE DISTORTION IS CREATED.
But what will happens is you turn the eye a bit away from the center and look through the part of the lens where you made the compensation?
My point is that this feature is not possible and ones again an created story from the industry, (I will eschew to call it BS).
Mike

[Fezz]

*********Stretch-----------YAWN-----------Stretch*********

[YrahG]

Okay, I will try to put this down on paper.
What we are talking about here (just to make sure everyone and my self understand prober) is the distortion the Cornea create in the peripheral part of cornea (that is aprox. 2 mm from the center). In the theory it can be possible to compensate for the distortion in the lens IF THE PERSON IS ALLWAYS LOOKING STRAIHGT AHEAD, AND IF YOU KNOW HOW THE DISTORTION IS CREATED.
But what will happens is you turn the eye a bit away from the center and look through the part of the lens where you made the compensation?
My point is that this feature is not possible and ones again an created story from the industry, (I will eschew to call it BS).
Mike

You have been following the wrong thread, the spherical aberration being talked about is on the surface of the lens, the front surface to be exact. Nothing to do with the cornea. The pupil size is only relevent because it will determine the amount of rays that can enter at any one time, hence sph abe and coma.

At this point it really seems like you are more intent to be right than to discuss the facts and potential benefits (again I said potential). I don't have the time to teach you optics and you don't seem to have the patience to read a book, so we are at an impasse.