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Chemists discover how blue light speeds blindness

phys.org

31–40 of 345 posts

Re: Chemists discover how blue light speeds blindness

#32
post #19

> To protect your eyes from blue light, Karunarathne advises to [...] avoid looking at your cell phones or tablets in the dark. Can someone explain why it would be worse to look at a cell phone in the dark? It's emitting the same blue light (or less, if the display gets dimmer) as it is in a bright environment. Why is that light more harmful in a dark environment?

Because of the way your eyes work. If it is bright, your pupil will be shrunk, to not be blinded by the luminosity. When it is dark, your pupil will be opened wide up.

It is this principle that camera apertures are based on.

Now if you have your pupil wide open in a completely dark environment and put a 100% brightness screen at ~10cm of your eyes, what do you expect will happen ? Our eyes are made for nature, that means day and night, now we have technology that is akin to a handheld sun and you use this at night at 10cm of your face, our eyes are simply not equipped to handle this.

Re: Chemists discover how blue light speeds blindness

#35
post #7

Earlier quoted context omitted.

Wait, is UV light bad for your eyes? Should I be careful about visiting bars with UV light too?

Yes, UV rays cause damage to pretty much any organic matter, that's the reason we wear sunscreen, sunglasses, and why cheap "fake" sunglasses can be harmful for your eyes (the glass is simply tinted and does not filter out the UVs, which is what they should be doing) edit: the way I remember it is that like any type of radiation, anything that goes into your body stays there pretty much until your death, the only way…

I just wanted to point out that most cheap (and therefore plastic) sunglasses are actually perfectly fine in terms of UV protection. Polycarbonate is UV opaque.

If you Google this subject there are several websites where people went out and bought cheap an expensive sunglasses and had them tested and reached the same conclusion: UV protection does not justify expensive Raybans.

Re: Chemists discover how blue light speeds blindness

#36
post #32
post #19

> To protect your eyes from blue light, Karunarathne advises to [...] avoid looking at your cell phones or tablets in the dark. Can someone explain why it would be worse to look at a cell phone in the dark? It's emitting the same blue light (or less, if the display gets dimmer) as it is in a bright environment. Why is that light more harmful in a dark environment?

Because of the way your eyes work. If it is bright, your pupil will be shrunk, to not be blinded by the luminosity. When it is dark, your pupil will be opened wide up. It is this principle that camera apertures are based on. Now if you have your pupil wide open in a completely dark environment and put a 100% brightness screen at ~10cm of your eyes, what do you expect will happen ? Our eyes are made for nature, that m…

My phone (unlike my PC, or a TV) is smart, and thus dynamically alters brightness based on ambient light. It's pretty cool and certainly mitigaets the above somewhat

Re: Chemists discover how blue light speeds blindness

#37

Can anyone recommend editor color schemes that look good when f.lux is set to heavily filter blue light?

I’ve really started to like gruvbox lately. It’s naturally a warm color theme already so I would imagine it should still look good under a heavy blue light filter.

Re: Chemists discover how blue light speeds blindness

#39
post #19

> To protect your eyes from blue light, Karunarathne advises to [...] avoid looking at your cell phones or tablets in the dark. Can someone explain why it would be worse to look at a cell phone in the dark? It's emitting the same blue light (or less, if the display gets dimmer) as it is in a bright environment. Why is that light more harmful in a dark environment?

Your pupils are dilated; you're receiving more light.

[deleted]

Re: Chemists discover how blue light speeds blindness

#40

I use f.lux all day I don't know if I'm particularly sensitive or if it's all in my head but when I turn off f.lux, especially at night, to watch some movie or video I can physically feel my pupils dilate and it almost feels like my eyes go from being at rest to being strained.

I use something similar to flux for my lightbulbs, and I've noticed the same thing when I disable it at night. My eyes are definitely strained.
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