A quick follow up to yesterday’s blog post. I was finishing lenses for a patient today and wanted to share a great visual representation of what astigmatism looks like in a pair of glasses.
Below are two images, one is a front view of a lens, in which you can see reflections from the fluorescent lights. You’ll notice how one reflection is “square” with the frame and the othere is on a sharp angle, almost 45 degrees off the first. The first reflection is from the front of the lens, where there is no cylinder/astigmatism correction. The second, severely angled reflection is from the backside of the lens where the cylinder is ground into the lens.
Cylinder in Reflection
The second image here, shows a side view of that same lens where you can see the variability in lens thickness, which matches the angle and severity of the astigmatism correction.
The “Cylinder” of Astigmatism
I hope you’ve enjoyed this update…
THE OPTICAL JEDI: A GUIDE TO THE MYSTERIES OF GLASSES 
Since I have a pretty strong astigmatism in my right eye, this is fascinating! I would like to hear more about how our lenses are made, and how they correct our vision.
Also, my eye Doctor told me that if a person has a strong astigmatism in only one eye, it was most likely due to a blow to that side of the head. It’s true for me! And 8f it’s in both eyes it was probably caused by forceps used at birth. I’d like to get your take on that theory.
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Hi Brenda.
There are many theories but there is no question that genetics can be a part of it. I have seen heavy astigmatism through generations in families.
I will post more on this soon. I’m in the middle of an educational vacation for my daughter visiting all the missions in California
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