Lens shape and astigmatism

I am wondering if anyone has information regarding the effect of the lens shape on the visual system.
I am specifically interested in astigmatism because i have about -3D astigmatism.

Most of my adult life I have used rectangle lenses which are very wide (say 1:2 height to width ratio)
I happen to have astigmatism with axes between 85 to 110, which means that I have more correction in the longer part of my lens.

My thinking is maybe it helped induce the astigmatism, and maybe i should order glasses that are more round shaped.


I just made a post about astigmatism in another thread. I think it is more relavent here.

I suspect astigmatism is related to brain & Eye miscoordination rather than any problem with the eye (or size of eye or shape of eye). And the fixed focal plane of glasses really amplify this miscoordination.

Here, I think we need to understand the role of blur. When normal people (without glasses) see clearly, do they see no blur? Practically, they don’t see blur, but actually, they are ignoring large amounts of blur. Let me explain…

When a person focuses (zooms in) on a text, the text becomes more clearer but everything else in the background goes out of focus (i.e. it becomes blurred). So, ironically, you can see the clearest when your mind-eye are concentrating on a small part & everything else is blurrred. Normal people don’t notice the blur because their mind-eye coordination is so good that it constantly and quickly adjusts to what they see. (bringing the target into focus and blurring the background).

Now, if that mind-eye coordination is broken for some reason, then there is ghosting or variable blur(Travelling blur). Basically, the mind-eye are trying to work out a working relationship (what to bring into focus and what needs to be blurred & ignored). Now, add fixed focal plane glasses into this mix and the mind-eye coordination is completely broken.

So, how does Active Focus address the astigmatism?
Well, it is easy to zoom in on text and align a text (in case of ghosting). Basically, it allows the mind-eye to arrive at a working relationship. Remember, there are 2 eyes with 2 different seeing capabilities. Further, each eye can and does vary focal length. The brain has to put the differing quality images from these varying sources into a understandable format and then the mind (conscious part) reads it. Given, so many factors and variables, it is easy to see that miscoordination can develop, once in a while. The way to clear it is by just doing basic coordination in a familiar territory i.e. active focus on text.


From what I’ve seen, the lens starts out round. The shape it is cut to after manufacturing should have no effect. As long as your PD is correct and you are looking through the optical center of the lens, then the shape of the frame should be irrelevant.

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Yes the lens is indeed round (or oval if you have astigmatism)

but the periphery around the lens has a certain shape to it, and light coming from the periphery might affect the visual system somehow.

Yes, it’s an extension of the problem that contacts are meant to solve. There’s an irregularity based on the border and shape of the cut of the lens.

I’m a lot happier in square rather than rectangular frames. I’m a lot happier in clear than brown or black frames. I’m a lot happier without lenses at all when I can get away with it.

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I guess perfectly round lenses could possibly even out what ever disturbance the edge finish is causing. All I’ve ever detected is a slightly illuminated edge that is detectable around my field of vision.

Now that you guys have me looking I do notice a difference with my differentials which are semi-rimmed. The black top edge creates much less visual disturbance than the clear line on the bottom.

Aren’t optical equipment lens edges normally blacked out or something similar?

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