Most of the visibility commentary comes from addressing claimed equivalencies being drawn between IR and visible light flashes and the effect those can have, which aren't the same.
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iPhone X FaceID and eye safety
- Thread starter stafil
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As with many things, a small amount of real science wrapped up in misunderstanding and false conclusions can result in a lot of misplaced fear.
Infrared (radiant heat) is absorbed by the lens of the eye, and doesn't make it to the retina. FaceID projects a low power, dispersed dot cloud, with a very low W/cm^2 (otherwise it would DESTROY battery life!)
If you have ever stood in front of a flame or other heater, or been outside with the sun on your face (even without looking at or near the sun) your cornea has been exposed to FAR more IR than you are ever likely to accumulate by using FaceID.
There are standards that govern how much IR exposure is safe. These lean heavily on the safe side. If FaceID did not comply with this, it would never have been allowed to be released for public use.
Or, another question for you: Does FaceID make your face hot? If not, how could it possibly damage you???
Infrared (radiant heat) is absorbed by the lens of the eye, and doesn't make it to the retina. FaceID projects a low power, dispersed dot cloud, with a very low W/cm^2 (otherwise it would DESTROY battery life!)
If you have ever stood in front of a flame or other heater, or been outside with the sun on your face (even without looking at or near the sun) your cornea has been exposed to FAR more IR than you are ever likely to accumulate by using FaceID.
There are standards that govern how much IR exposure is safe. These lean heavily on the safe side. If FaceID did not comply with this, it would never have been allowed to be released for public use.
Or, another question for you: Does FaceID make your face hot? If not, how could it possibly damage you???
Yeah, I got red spots all over my forehead from that thing firing up on me all day! LOL
Thanks for the post, I appreciate your response makes sense to me, but you know we live in conspiracy times, so there will be those that won't believe what you are saying.
Even in that case there is a possibility of lens damage.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3116568
"IR exposure (770 nm–3 µm) should be limited to 10 mW/cm2 for lengthy exposures (> 1000 seconds), and to 1.8 t–3/4 W/cm2 for shorter exposure durations"
Unfortunately Apple doesn't publish info about its "Flood Illuminator".
However I wonder if we could extrapolate it. For example the VL53L0X is a 940nm with max average power consumption of 20mW.
Assuming a radius of 35 degrees and distance of 30cm, this would be a circular area of 19cm diameter, which give us a surface of 200cm2. Which means 0.1mW/cm2.
Now if I am not mistaken, VL53L0X is what the pre X iphones are using for the proximity sensor. I would say the intensity of the "flood illuminator" is at least 10 times stronger?
So we are at 1mW/cm2
As for the duration, well it's up to the use of the phone.
Are my math above/assumptions above correct?
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Also what you say is part correct. Near-infrared does reach the retina.
https://saunaspace.com/wp-content/uploads/2015/03/Radiation-effects-on-the-eye.pdf
OK, so without checking through your maths, what you've discovered is if we take a generous x10 increase in power over an example IR range finder, then it is still 1/10th of the flux that could cause damage if someone were to implement a completely ridiculous use-case of rapidly and repeatedly locking and unlocking their phone as fast as they can, sustained for over 15 minutes.
Some near IR can reach the retina. We don't know what wavelength is used for Face ID. In this case, it's best to go by standard laser safety numbers, i.e. the limit for Class 1 lasers (which are 100% eye-safe) is 1 mW. So depending on the size of your pupil, IR flux of over 1 mW/cm^2 would still be retina safe. Depending on the wavelength used, the safe-level would rapidly increase as wavelength increases. So again, not even close to dangerous.
EDIT: Additionally, FaceID is probably pulsed, further lowering the average IR flux.
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All above are good, assuming you are in the "short term" category. But I don't think that's the case.
Do you think the flash duration is at least 250ms? That means 3 seconds in the minute? With 8 hours screen time average a day, that's already above 1000sec in a single day. Multiply it by 365, and we are way above the "short term".
I don't think it falls in the short-term category.
It is INVISIBLE, like ALL the rest of invisible radiation that hits your eyes EVERY second you are alive in this earth.
As long as it is non-ionizing energy (and it is). It is harmless.
As long as it is non-ionizing energy (and it is). It is harmless.
what about the fact that the flood illuminator is surely not a frickin' LASER but rather a simple emitter?
You're going way off track here, short-term and long-term refer to continues exposure with no rest. Over the course of a day means little, when you're talking very little exposure. Are you actually staring at your phone for 8 solid hours a day with your eyes rested up against this LED?
OK so let's think this through. According to https://appleinsider.com/articles/1...est-selling-smartphone-model-in-first-quarter, Apple shipped 16,000,000 iPhone X units in Q1 of this year. Safe to say they've sold more since, but we'll go with that number. Now, you claim that hundreds of people are complaining about eye problems. Let's say that only one in three complain, two out of three are out there, suffering in silence. Is that fair? How about one in four. That would mean that your hundreds, which I will generously set at 900, are in fact more like 3600 people affected. Seems fair? Here's the math: 3,600 out of 16,000,000 phones sold is a whopping 0.025% of users. Not exactly a compelling case for a class action lawsuit!
And remember, that number is based on *just* Q1 sales, I imagine they've sold a few million more by now, not even counting XS and XR. And that's assuming you didn't just make up your numbers, which you surely did.
As New_Mac_Smell said, it's not about accumulated time over the day, but sustained time.
IR radiation does not have the energy to cause damage directly. It instead results in heat being generated, which if allowed to accumulate, can cause damage.
If you rest your eyes for a few minutes, or even every time you blink, that heat is transported from your cornea. If your viewing is such that your cornea never gets to a temperature where damage is being done, then how many hours a day you're staring into the device is irrelevant.
Also, no way is FaceID operating constantly during use of your phone. It would be an unnecessary power drain. So unless you are playing with Animoji for 8 hrs every day, even your suggested scenario (which wouldn't be a problem anyway as already covered) would never happen.
EDIT: It's probably worth noting also that the study that you linked to previously (source of 10 mW/cm^2) was conducted on rabbits. Humans blink an awful lot more often than rabbits do, which would help to transport heat away.
Yikes! No! No! No! This is completely untrue.
FaceID is almost certainly safe, but not for this reason.
Non-ionizing radiation can still be harmful. Remember, a microwave oven emits invisible non-ionizing radiation...
I haven't take measurements on it, but I'd be astounded if it was allowed to ship without meeting eye safety limits. You can severely damage your retina with IR even though you can't see it. In some ways, invisible light is more dangerous than visible because your pupils don't close and it doesn't trigger a blink reaction or cause you to look away.
Do you mind if I ask where you got your knowledge on the subject from? Genuinely asking, and not afraid to say that my knowledge is from the papers that I linked here, my experience with the phones, other peoples feedback and my experiments.
What’s the difference? Your eye is designed to take light from a point and focus it back to a point. The sun isn’t a frickin’ laser, but put a lens in front of it and you can torch ants.
Bachelor's degree in Physics, PhD in Engineering, previous academic work with lasers and resulting safety information, some logical thinking and reasoning, a quick skim of the key points in the papers, and some light googling.
Do I get the job?
Bachelor's degree in Physics, PhD in Engineering, previous academic work with lasers and resulting safety information, some logical thinking and reasoning, a quick skim of the key points in the papers, and some light googling.
Do I get the job?
Thanks
Pretty much. Whether it's a laser or a lamp, all that matters is the amount of energy that hits your eye. If we're talking about the cornea, then that's as much as we need to consider. If we're talking about the retina, then it also matters if the energy comes from a point, or a diffuse light source, because of the lens which will focus point light sources, but cannot focus diffuse light.
If I put some room temperature food in the microwave, and power it on for 1 second of every minute, for an hour, will it be as hot as if I put it in for 1 continuous minute?
Does that mean you believe me, and you'll stop worrying that FaceID will blow up your eyeballs like the Death Star?Thanks
No, but thanks for answering my question.
While you made some good points, I think you fell into contradictions and were wrong about a couple others.
But don't get it to personally, I will not believe (almost) anyone until I see the official specs form Apple, or find very very expensive equipment and measure things myself.
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It's not only the thermal damage, but also the chemical/radiation damage, that does accumulate.
https://www.renesas.com/us/en/doc/application-note/an1737.pdf
No, but thanks for answering my question.
While you made some good points, I think you fell into contradictions and were wrong about a couple others.
But don't get it to personally, I will not believe (almost) anyone until I see the official specs form Apple, or find very very expensive equipment and measure things myself.
[doublepost=1540874175][/doublepost]
It's not only the thermal damage, but also the chemical/radiation damage, that does accumulate.
https://www.renesas.com/us/en/doc/application-note/an1737.pdf
If you need to measure things yourself, are you qualified to understand the results? Not being funny but I'd trust someone with even a BSc in Physics over my own observations... You'll never get the specifications, so you'll never satisfy your own desire here.
Honestly just get rid of the phone and use something else if it's going to dominate so much of your time to pseudo-scientific study. You'd be better off going to University and studying this stuff than reading papers you can't fully interpret, based on bolding of specific areas which meet your criteria over analysing a paper as a whole.
I'm sure you could just put the phone in a box with an organic object and measure the effects using readily available things. But as you said you wouldn't believe anything then there's no point, this is just hyperbole nonsense for no reason. Many people have tried to explain the technology behind it, and the scientific effects of it, but you're not willing to listen to anyone but yourself - which I hope you understand is a very flawed position to take, no scientist would trust their own opinion over peer reviewed and replicated studies.
Best of luck I suppose, it's interesting reading from my perspective at least.
Well, feel free to point them out, and I'll do what I can to clear them up. Of course, at some point you have to ask yourself if you really can be convinced, if not there's really no point.
Well, consider that if everything I (and many others here) have said is wrong, and FaceID is dangerous, then in a couple of decades when we're all blind we can sue Apple and buy ourselves some brand new cyborg eyes that are better than the originals. Apple will probably be selling them.But don't get it to personally, I will not believe (almost) anyone until I see the official specs form Apple, or find very very expensive equipment and measure things myself.
"Trade in your old iPhone X/Xs for a free pair of AppleEyes Today!"
I’m pretty sure the OP wouldn’t believe Albert Einstein if he determined Faceid was harmless...
Well, that's your mistake, and to be honest it's one that I would not think an educated person like you to do: I am not here to be convinced or convince you.
I am here to express my ideas, reasoning and thoughts, and learn from yours. And have learned quite a few things for sure. If you manage to weed out the trolls, you do get a lot of food for thought.
If the things that I learn will alter my views and reasoning and find a way to change my opinion at some point in the future is completely secondary.
Not quite sure what my "mistake" is. I've made it pretty clear my background is in Science, Technology, Engineering and Maths (STEM), where ideas, reasoning and thoughts are either correct, or incorrect. I'm not saying I'm always right, but FaceID is either safe to use, or it's not. Views and opinions are relevant in Arts and Politics, but not in Science and Engineering problems, like this. The exchange of ideas, reasoning and thoughts in an Engineering-based situation is meaningless if it does not eventually result in one side or the other being convinced, and eventual consensus.
So basically, what I'm saying is your admission that you cannot be convinced is an admission that this entire thread is, and has always been, pointless.