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Comment by naoru | Hacker News Reader

Personal anecdote: I was born with astigmatism, hypermetropia with over 3 diopters difference between eyes, a slight esotropia, which was partially corrected by training, and have developed amblyopia as the result of all that.

Naturally, I didn't even know about stereo vision, everything was flat and that didn't bother me.

But when I was about 20 years old, my friend showed me Virtual Boy. After looking into the headset I immediately sensed the depth and was blown away with it.

Even after I took off the headset, depth perception didn't go away ever since. It only became much stronger when I started wearing contact lenses.

Sorry for possible grammar mistakes, I haven't yet experienced anything like Virtual Boy but for English, which is not my first language.

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People advertise contact lenses as a fashion thing. "No ugly glasses." But the biggest benefit of contact lenses is IMO "no pincushion/barrel distortion". Especially if you need different correction for each eye, it can make a big difference. I think a lot of people who wear glasses don't know you can avoid the distortion with contact lenses.

Glasses have saved my sight in an eye twice. Once was avoidable stupidity (kids are dumb), once was unavoidable. I see them as protective as much as for vision now. I don't want contacts.

You can still wear contacts for improved vision and then wear actual safety glasses that are designed to meet standards for protecting your eyes. Don't rely on the accidental strength of prescription glasses.

They're also much cheaper to replace than prescription glasses when damaged or scratched.

Safety glasses come in many models today - many look like sport sunglasses and come in clear, tinted, yellow, and shaded.

One other seriously negative thing about contacts is that unless you are fastidious about cleaning or disposing them you risk eye infections, which could potentially be very serious.

I used to wear disposable lenses, but out of lazyness and frugality, I'd leave them in longer than I should have and suffered multiple eye infections. Fortunately, no serious harm resulted from them, but I recognized the risk and eventually switched back to wearing glasses. Since then I've never had to worry about that stuff ever again.

I've used hard (gas-permeable) lenses for 35 years without problems, but then I take them out every night and clean them. It's not nearly as difficult to keep them clean as it is with soft/disposable ones.

That is probably because you're using something like ClearCare which is a buffered hydrogen peroxide (with some other stuff) and a case that acts as a catalyst. The peroxide sterilizes your contacts, the catalyst slowly converts all the hydrogen peroxide to water. It takes at least 6 hours and you have to change the case out with every new bottle every month or so or else you get hydrogen peroxide in your eyes, which even in small amounts is really awful. I use to use the stuff by choice because it helped my eyes feel more comfortable vs the other contact lens solutions (except for the days I was lazy and didn't change out the cases or over wore my lenses past the X amount of days before disposal). I had soft contacts, that's why it was a choice, but I'm pretty sure hard contacts require the use of this type of cleaning method. Now I use dailies because they're more comfortable even though they're crazy expensive.

Can contact lenses do cylinder correction nowadays; is there a "this side up"-sort of orientation to them?

Yes, they're called toric lenses: https://en.wikipedia.org/wiki/Toric_lens

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