We’re often warned about how dangerous small commercial lasers can be for our eyes yet technologies like FaceID projects light in our faces many times a day.
Why is FaceID safe? Because it’s low enough power or because it’s in the non-visible spectrum?
Can the non-visible spectrum be dangerous for our eyes?
In: 40
There are two types of light outside the visible spectrum. Infrared and Ultraviolet. And those are completely different things. Things like FaceID and night vision cameras and the like use infrared. This is basically harmless to us, at least compared to visible light. It is technically possible to get too high concentration of IR light just as visible light and this may burn you. Especially the eyes as you do not have the same reflexes for IR light as for visible light. This is why powerful IR lasers have the same warning stickers as visible light lasers. However consumer products do not contain these types of powerful lasers, and if they do they are not exposed to the user.
Ultraviolet does have the same issues as IR and visible light when it comes to the powerful concentrated lasers that can burn you. But in addition to this UV light is at the lower end of ionizing radiation. This is the type of radiation which can damage tissue and cause things like radiation burns and cancer. This can happen at much lower intensities. So even non-lasar UV lights will come with warnings and shields preventing people from being exposed to it.
We’re often warned about how dangerous small commercial lasers can be for our eyes yet technologies like FaceID projects light in our faces many times a day.
Why is FaceID safe? Because it’s low enough power or because it’s in the non-visible spectrum?
Can the non-visible spectrum be dangerous for our eyes?
In: 40
There are two types of light outside the visible spectrum. Infrared and Ultraviolet. And those are completely different things. Things like FaceID and night vision cameras and the like use infrared. This is basically harmless to us, at least compared to visible light. It is technically possible to get too high concentration of IR light just as visible light and this may burn you. Especially the eyes as you do not have the same reflexes for IR light as for visible light. This is why powerful IR lasers have the same warning stickers as visible light lasers. However consumer products do not contain these types of powerful lasers, and if they do they are not exposed to the user.
Ultraviolet does have the same issues as IR and visible light when it comes to the powerful concentrated lasers that can burn you. But in addition to this UV light is at the lower end of ionizing radiation. This is the type of radiation which can damage tissue and cause things like radiation burns and cancer. This can happen at much lower intensities. So even non-lasar UV lights will come with warnings and shields preventing people from being exposed to it.
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