Recently, I replaced my 1.61 index lens with 1.67 and the prescription is the same. But after that, I felt some strain in my eyes. Is this a lens quality issue? - Quora
![Comparison of central thickness of +3.00 lens (up) and edge thickness... | Download Scientific Diagram Comparison of central thickness of +3.00 lens (up) and edge thickness... | Download Scientific Diagram](https://www.researchgate.net/publication/350666756/figure/fig1/AS:1009631858028550@1617726401609/Comparison-of-central-thickness-of-300-lens-up-and-edge-thickness-of-300-lens.jpg)
Comparison of central thickness of +3.00 lens (up) and edge thickness... | Download Scientific Diagram
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