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
![Help me figure out how thick my eyeglass lenses will be. - glasses prescription index | Ask MetaFilter Help me figure out how thick my eyeglass lenses will be. - glasses prescription index | Ask MetaFilter](http://static.zennioptical.com/image/common/static/Index-Comparison.jpg)
Help me figure out how thick my eyeglass lenses will be. - glasses prescription index | Ask MetaFilter
![Index 1.57 Aspheric Photochromic Single Vision Lens Ar Coatings / Prescription Lens / Transition Lens/brown Gray - Eyeglasses Lenses - AliExpress Index 1.57 Aspheric Photochromic Single Vision Lens Ar Coatings / Prescription Lens / Transition Lens/brown Gray - Eyeglasses Lenses - AliExpress](https://ae01.alicdn.com/kf/HTB1a1UcKpXXXXbJXVXXq6xXFXXXF.jpg_640x640Q90.jpg_.webp)