Could we just have rooms lit as strongly as outdoors?
Sometimes, the glass ceiling isn’t a metaphor.
Shortsightedness has become an epidemic
211–220 of 424 posts
Re: Shortsightedness has become an epidemic
#212Earlier quoted context omitted.
I have very bad eyesight too. May I ask what is your correction? (Not sure it’s the proper word in English, but the thing measured in dioptres?)
Not him, but myopia is the correct medical term. It only has one meaning, whereas "short-sighted" has a widely used metaphorical meaning that it is easily confused with.
msk wanted to know thethe guy’s prescription
Re: Shortsightedness has become an epidemic
#213Why 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.…
How would it work? Where would you put the two lenses? Consider: - You can't really have two lenses cemented together. That'll correct for chromatic aberration but, other than that, the lenses would behave as one (except for deviations from thin lens approx.) - You can't have glasses mounting two lenses "d" apart for two reasons. 1) Having parallel lenses would terribly uncomfortable, heavy, and awkward 2) More impor…
I think GP is mistaken about two physical lenses being needed (until it's the future and we're all wearing expensive smart glasses, in which case you do want an additional interchangeable lens for this purpose). When designing the system, it can be thought of as a lens that corrects for refractive error of the relaxed eye (moving the eye's far point to infinity) stacked on top of another lens that makes light coming from an object parallel (producing an image of the object at infinity for the first lens and eye to receive); to implement it, you only need one lens with the combined power of the two.
Edit: GP might also be talking about eyeglasses with adjustable focus, which apparently are already available. https://en.wikipedia.org/wiki/Adjustable-focus_eyeglasses
Re: Shortsightedness has become an epidemic
#214I didn’t realize the evidence is strong that daylight keeps kids from becoming near-sighted. Making young kids study all the time is killing their eyesight!
I spent all my childhood outside and still near-sighted.
I spent all my childhood (and continuing into adulthood) staring at a computer screen and I've 20/20 vision.
Re: Shortsightedness has become an epidemic
#215Pet peeve about language use: I thought it was obvious that short-sightedness (Exclusively Short term thinking) is an epidemic, nobody on Wall Street can see past the next Quarter's numbers. I don't need the economist to point that out. Nearsightedness is what this article is about... a completely different thing. I've dealt with that my entire life... and just went through the knock-on effect of retina detachment, a…
Sorry, but in Australian English, those with myopia are always referred to as being short-sighted. The metaphor, having lack of foresight, is also referred to by the same expression.
Re: Shortsightedness has become an epidemic
#216I didn’t realize the evidence is strong that daylight keeps kids from becoming near-sighted. Making young kids study all the time is killing their eyesight!
Anecdata, but I lived in a low light environment for most of my life (North UK), then spend the last ~15 years in a much brighter environment (NZ). My prescription has dropped from a mid -5 to a low -4 in that time, which is a fairly large and uncommon improvement for someone middle aged. The optician put it down to where I've been living.
Decreased myopia is very common in middle-aged people. Mine went from -2 to 0 in my 40s. I did not move to New Zealand.
Re: Shortsightedness has become an epidemic
#217For several decades it has been known that myopia (nearsightedness) and intelligence are correlated[1][2]. Initially it was speculated that reading caused nearsightedness, and through that higher intelligence. There is probably some truth to that. But with modern DNA sequencing techniques researches has found genes that seem to affect both[3][4]. The hypothesis is that one (or a set of) genes affects both eye size gr…
The issue with these types of studies though is that there's no way to really parse out correlation vs causation, either between these two variables or with social factors at large. Especially in this case there was no molecular work done to validate the hits or establish causal pleiotropic effects. The authors are incentivized to tell a story but as readers I think we can be a little more skeptical and evaluate the…
I agree with this…
I don’t think other studies on myopia fit this same narrative. (However I may be wrong!)
Re: Shortsightedness has become an epidemic
#218For several decades it has been known that myopia (nearsightedness) and intelligence are correlated[1][2]. Initially it was speculated that reading caused nearsightedness, and through that higher intelligence. There is probably some truth to that. But with modern DNA sequencing techniques researches has found genes that seem to affect both[3][4]. The hypothesis is that one (or a set of) genes affects both eye size gr…
And here I am thinking my perfect eyesight at 45 is a good thing :(
Re: Shortsightedness has become an epidemic
#219For several decades it has been known that myopia (nearsightedness) and intelligence are correlated[1][2]. Initially it was speculated that reading caused nearsightedness, and through that higher intelligence. There is probably some truth to that. But with modern DNA sequencing techniques researches has found genes that seem to affect both[3][4]. The hypothesis is that one (or a set of) genes affects both eye size gr…
Quoted post unavailable.
That's the cool thing about science, it can't be refuted by one person's anecdotal experiences.
Re: Shortsightedness has become an epidemic
#220For several decades it has been known that myopia (nearsightedness) and intelligence are correlated[1][2]. Initially it was speculated that reading caused nearsightedness, and through that higher intelligence. There is probably some truth to that. But with modern DNA sequencing techniques researches has found genes that seem to affect both[3][4]. The hypothesis is that one (or a set of) genes affects both eye size gr…
I thought the increase in nearsightedness originated in kids not playing outside as much (and thereby not focusing their eyes over longer distances) resulting in eyesight that's more attuned to shorter distances.