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319 points doctoboggan | 3 comments | | HN request time: 0.006s | source
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suprnurd ◴[] No.46235191[source]
Where I live I am often surrounded by Waymo vehicles... is Lidar 100% safe for people to be around? I ask because I read an article about how Lidar on one of the new Volvos could destroy your phone camera if you pointed it at it? If Lidar can do that to a phone camera, can it hurt your eyes?
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filoleg ◴[] No.46235432[source]
Your eyes will be fine (assuming that we are talking about automotive LiDAR specifically).

Automotive LiDAR is designed to meet Class-1 laser eye-safety standard, which means "safe under normal conditions." It isn't some subjective/marketing thing, it is an official laser safety classification that is very regulated.

However, if you try to break that "normal conditions" rule by pressing your eyeball directly against an automotive LiDAR sensor for a very long period of time while it is blasting, you might cause yourself some damage.

The reason for why your phone camera would get damaged, but not your eyes, is due to the nature of how camera lenses work. They are designed to gather as much light as possible from a direction and focus it onto a flat, tiny sensor. The same LiDAR beam that is spread out for a large retina can become hyper-concentrated onto a handful of pixels through the camera optics.

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tennysont ◴[] No.46235550[source]
Why wouldn’t your eye lens focus LIDAR photons from the same source onto a small region of your retina in the same way that a phone camera lens focuses same-origin photos to a few pixels?

Sorry if this is a silly question, I honestly don’t have the greatest understanding of EM.

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dllu ◴[] No.46235749{3}[source]
Depends on the wavelength of lidar. Near IR lidars (850 nm to 940 nm, like Ouster, Waymo, Hesai) will be focused to your retina whereas 1550 nm lidars (like Luminar, Seyond) will not be focused and have trouble penetrating water, but they are a lot more powerful so they instead heat up your cornea. To quote my other comment [1]:

> If you have many lidars around, the beams from each 905 nm lidar will be focused to a different spot on your retina, and you are no worse off than if there was a single lidar. But if there are many 1550 nm lidars around, their beams will have a cumulative effect at heating up your cornea, potentially exceeding the safety threshold.

[1] https://news.ycombinator.com/item?id=46127479

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1. stoneman24 ◴[] No.46235950{4}[source]
Do you if there has been any work how lasers affect other animals and insects?

Am I being catastrophically pessimistic to think that in addition to swatting insects as it moves forward, the cars lidar is blinding insects in a several hundred meter path ?

I’m very optimistic about automated cars being better than most humans but wonder about side effects.

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2. fragmede ◴[] No.46239522[source]
If we have automated anti-mosquito vehicles just roaming around, the world would be a better place. There might be some second order effects from removing mosquitoes that we haven't predicted, but fuck mosquitoes.
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3. dash2 ◴[] No.46240014[source]
Unfortunately not all insects are mosquitoes, and one reason we have many fewer birds in (e.g.) the UK than when I was young, is the decline of insect life.