4 ms·

"8 IR illuminators per eye" Honest question: is there any reason to be concerned about such near and constant IR illumination directed at one's eyes?

hammock 4y ago
I guess it would be like looking up at one of those security cameras that are ringed with IR LEDs
daniel_reetz 4y ago
Generally with near-infrared emitters, the main issue is tissue heating up. Of course this depends on the tissue, the specific wavelength(s), and the angular distribution of the emitter. OSRAM has an excellent datasheet about this, AN090 . If you're curious about how this kind of thing is safely engineered, have a look!
- daniel_reetz 4y ago
  Also the reason for 8 emitters is to have lots of points to track, not to provide a huge amount of light.
deleted 4y ago
[deleted]
lizardactivist 4y ago
No, it's an insignificant increase over what your eyes already receive.
- andai 4y ago
  Does that account for the fact that it's decoupled from visible light? Afaik the iris contracts in response to visible light, so here could get exposed to more IR proportionally. (OTOH either way in absolute terms the amount you get from sunlight is orders of magnitude more than you'd get from a few LEDs.)
ta988 4y ago
Old tracking systems I tried were really uncomfortable due to that and couldn't be used long. Hope these are better (disclaimer it was 10 years ago).
aaaaaaaaaaab 4y ago
“The most common eye disease associated with near-infrared radiation is cataracts. Prolonged exposure to IR radiation causes a gradual but irreversible opacity of the lens. Other forms of damage to the eye from IR exposure include scotoma, which is a loss of vision due to the damage to the retina. Even low-level IR absorption can cause symptoms such as redness of the eye, swelling, or hemorrhaging.” https://ehs.lbl.gov/resource/documents/radiation-protection/non-ionizing-radiation/light-and-infrared-radiation/ https://ehs.lbl.gov/resource/documents/radiation-protection/...
spyder 4y ago
It may even improve eye-sight in the short-term: https://www.newscientist.com/article/2298723-red-light-therapy-could-improve-eyesight-that-has-declined-due-to-age/ https://www.newscientist.com/article/2298723-red-light-thera... I'm not sure about the energy and wavelength difference compared to the glasses. But even if it has a positive effect from short-term exposure, it may also have bad effect from too much exposure.

hammock 4y ago

I guess it would be like looking up at one of those security cameras that are ringed with IR LEDs

daniel_reetz 4y ago

Generally with near-infrared emitters, the main issue is tissue heating up. Of course this depends on the tissue, the specific wavelength(s), and the angular distribution of the emitter. OSRAM has an excellent datasheet about this, AN090 . If you're curious about how this kind of thing is safely engineered, have a look!

daniel_reetz 4y ago
Also the reason for 8 emitters is to have lots of points to track, not to provide a huge amount of light.

deleted 4y ago

[deleted]

lizardactivist 4y ago

No, it's an insignificant increase over what your eyes already receive.

andai 4y ago
Does that account for the fact that it's decoupled from visible light? Afaik the iris contracts in response to visible light, so here could get exposed to more IR proportionally. (OTOH either way in absolute terms the amount you get from sunlight is orders of magnitude more than you'd get from a few LEDs.)

ta988 4y ago

Old tracking systems I tried were really uncomfortable due to that and couldn't be used long. Hope these are better (disclaimer it was 10 years ago).

aaaaaaaaaaab 4y ago

“The most common eye disease associated with near-infrared radiation is cataracts. Prolonged exposure to IR radiation causes a gradual but irreversible opacity of the lens. Other forms of damage to the eye from IR exposure include scotoma, which is a loss of vision due to the damage to the retina. Even low-level IR absorption can cause symptoms such as redness of the eye, swelling, or hemorrhaging.” https://ehs.lbl.gov/resource/documents/radiation-protection/non-ionizing-radiation/light-and-infrared-radiation/ https://ehs.lbl.gov/resource/documents/radiation-protection/...

spyder 4y ago

It may even improve eye-sight in the short-term: https://www.newscientist.com/article/2298723-red-light-therapy-could-improve-eyesight-that-has-declined-due-to-age/ https://www.newscientist.com/article/2298723-red-light-thera... I'm not sure about the energy and wavelength difference compared to the glasses. But even if it has a positive effect from short-term exposure, it may also have bad effect from too much exposure.