Ask HN: News site for prescription lenses technology
I was wondering if someone knows a good news site for news about eyecare technology. I always wondered why, for example, photocromic lenses don't exist above 1.71 index.
Lenses of an index higher than that are only available in glass but not many people will pay for or want to wear those because of weight issues.
Please keep in mind though that a higher index lens doesn't mean it's a better lens even though they're more expensive. As a general rule the higher the index the worse the optical properties. The only thing higher index lenses are good for is that they can be made thinner due to the way a higher refractive index material bends light.
Anyway to answer your question I'm not aware of any great site for optical news. It'd be nice if someone made one. I sometimes have a look at the following sites.
http://www.optmagazine.com //this one is a bit sarcastic