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Shortsightedness has become an epidemic

economist.com

111–120 of 424 posts

Re: Shortsightedness has become an epidemic

#112
post #8

Quoted post unavailable.

Agree man! Lockdown was just really unjustified on society. It made no sense for such a minor disease which I'm sure would have been dismissed as flu 60 years ago. I don't know what caused this overreaction, sure for 30-40 days but this thing has devastated billions of lives, left millions jobless and ruined an entire generation. It's sometimes necessary to have pandemics and diseases like this to control the populat…

2 million isn't few lives

Re: Shortsightedness has become an epidemic

#113
I've written about this before, but it bears repeating. However good your vision is when you're young, it will change as you get older.

Most people become more farsighted as they age. Typically it starts when you are around 40 and changes rapidly for the next decade. After that it tends to settle down.

More importantly, the lenses in your eyes become more rigid, losing their ability to focus at different distances.

When I was younger, one eye was a bit nearsighted and the other a bit farsighted. This allowed me to get away without glasses longer than I should have. Even if I wasn't seeing clearly with both eyes, I could see at most distances with one eye.

As my eyes' focus distance lengthened, my nearsighted eye attained close to normal vision, and my farsighted eye was focused past infinity. Not good.

When I got my first pair of prescription single vision computer glasses, it was life-changing. Now I could see my laptop screen perfectly. I told my optometrist I wanted something like single vision reading glasses, but adjusted for the distance to my laptop screen, about 20", unlike the typical 16" focus distance of a reading prescription.

In fact, this started to make me fussy about using high-DPI displays (~200 DPI) instead of the low-DPI displays (~100 DPI) I'd previously used. On a low-DPI display I could see the pixels!

It does mean that when I use external monitors with the laptop, I need to have them also at this 20" distance. So to augment the laptop screen, I have a 24" 4K monitor in landscape mode immediately above it, and a second 24" 4K monitor in portrait mode to the left.

Both of the external monitors are at about the same 20" distance from my eyes, and each of the three displays is angled differently so the center of the monitor is aligned with my vision: the laptop display at a typical laptop angle, the one above it closer to vertical (but still tilted a bit), and the one on the left at an in-between angle. The bottom of this monitor is about a half inch above my desk, just enough room to let cables run under it.

This is a fairly glorious setup. All three displays are in focus for me, and the portrait display is great for reading documentation, especially PDF files that are so awkward on a landscape display.

The key to this is the single vision glasses. I have seen so many people try to use progressive lenses with their computers, and they are always craning their neck back so they can see through the lower part of the lens that has a closer focus distance. Single vision lenses let everything be in focus at once, especially with the portrait mode monitor.

Another key is that the computer glasses should have a fairly tall profile, not the truncated rectangular lenses that are so popular. This greatly improves the field of view.

On my last visit to the optometrist they suggested lenses with a blue light filter. I said no thanks on that. Sometimes I do photo editing, and the blue light filter shifts everything to a warmer color. The way I solve the problem of too much blue light is that I simply don't turn my monitor brightness up so high. It is set so a white background is about the same brightness as a piece of white paper in the same lighting.

I also have progressive glasses that I use for everything else when I'm not at the computer. These have magnetic clip-on sunglasses, which are pretty great. Indoors I can leave the sunglasses off and just use the progressives on their own. Because I wear aloha shirts with a pocket, I can keep the sunglass lenses in my pocket and I hardly know they are there. When I step outside or go driving, I just snap on the magnetic clip-ons and I'm good to go.

The frames with magnetic clip-ons are a bit uncommon these days, but they are well worth finding.

If anyone is curious I can look up the brand and exact model number for both the round single vision and the progressives I'm using.

Re: Shortsightedness has become an epidemic

#114

I noticed my eyesight gets better after many hours outside not looking at any screen. And worsen after many hours in front of a screen. Is there a name for that?

I think it's multiple things.

Your eye is a muscle, focusing only at close range keeps the range of motion tight. Just like your back and neck might get stiff sitting all day.

Sunlight means smaller pupil, wider depth of field, just like a camera.

(My speculation) More light gives you brain more information to clean up or upscale a blurry image. This effect even seems to last when you leave sunlight, for awhile. It's like I fine tuned my neurons to prioritize blur reduction, and it takes awhile for them to fall back into normal processing. If this is true, my guess is that I might be trading off contrast or color details for sharpness.

Re: Shortsightedness has become an epidemic

#117

Anyone have an unlocked link?

Here you go: https://arxius.io/f/e9c469eb

Thanks, but the contents of your linked PDF, which is just plaintext, no images, is different from the Archive copy of the article shared up-thread here https://news.ycombinator.com/item?id=31712453

Did the Economist show you a different article with the same title due to your location?

Re: Shortsightedness has become an epidemic

#118

I've written about this before, but it bears repeating. However good your vision is when you're young, it will change as you get older. Most people become more farsighted as they age. Typically it starts when you are around 40 and changes rapidly for the next decade. After that it tends to settle down. More importantly, the lenses in your eyes become more rigid, losing their ability to focus at different distances. W…

Please share links, thanks.

Re: Shortsightedness has become an epidemic

#119

Why can we have 2-lense glasses that move the focus to infinity? ELI5: In opticals, “rays” coming from a near object (=mobile phone) are angled, while rays coming from afar (=end of a landscape) are parallel. The job of pupils is to bend the rays from the focal point ahead to the focal point on the receptors in the eye. The eye is a rest when looking afar, because rays come parallel, and thus there isn’t much to do.…

I think you get the effect you desire by wearing glasses with + when in front of a computer. anecdote: i started with -0.5 (10-15 years ago), per ophthalmologist "advice" wore glasses all the time (including computer), got to -1.75. then one summer spent some time without any glasses (just because i wanted to use the sunglasses) and at the end of the summer the vision went back to -1.50. This got me thinking that wearing glasses all the time is not that good. 4 months ago started to experiment, no glasses all the time and +0.5 when in front of the computer. Started with -1.25, and now I am at -0.50/-0.75 ... take it as you want.

Re: Shortsightedness has become an epidemic

#120

Quoted post unavailable.

This is a common figurative use of the word. The etymology comes from the Greek meaning "upon/on people", so nothing in the root connects the meaning to how something develops or spreads.

Then why not call it a "pandemic"? Shortsighteness has become a global phenomenon with more than one local maximum, hasn't it?
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