[suprnurd]

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?

[filoleg]

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.

[tennysont]

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.

[ramses0]

I looked this up for a laser-based projector, Class 2 is "blink reflex should protect you" and "don't be a doofus and stare into it for a long time". Look up the classifications on the google and you'll see other things like "don't look into the rays with a set of binoculars" and stuff.

Class 1 is pretty darned safe, but if you're continually bathed by 50 passing cars an hour while walking on a sidewalk... pitch it to a PhD student you know as something they should find or run a study on.

[mcdonje]

What about if you're walking or biking next to congested motorway and most of the vehicles have LiDAR running at the same time? That's a lot of photons.

[tonymet]

This is inconsistent with the basic concept. It’s projecting and reading lasers . By default some emissions will hit people in the eye. Even invisible light can damage tissue , especially in the eye

[OneDeuxTriSeiGo]

Depends on the type of LIDAR. LIDAR rated for vehicle use is at a wavelength opaque to the eyes so it hits the surface and fluid of your eye and reflects back rather than going through to your cones and rods.

It isn't however opaque for optical glass (since the LIDAR has to shine through optical glass in the first place) so it hits your camera lens, goes straight through, and slams the sensor.

[dllu]

You seem to be implying that all automotive lidar are 1550 nm but that's not true. While there are lots of 1550 nm automotive lidars (Luminar on Volvo, Seyond on NIO) there are also plenty of 850 nm to 940 nm lidars are used in cars (Hesai, Robosense, etc). Those can pass through water and get focused to your retina, but they are also a lot lower power so they do not damage cameras.

[kappi]

During the presentation, Rivian speaker specifically said it is safe for your camera sensors. Check the youtube video of their presentation

[colechristensen]

There are two kinds of safe. Safe when it's working as intended, and safe when it breaks.

But yes there are lidar sensors out there where if broken in the right way could burn out your retinas permanently.

[doctoboggan]

I watched the livestream and they said their hardware is "Camera Safe". I am not sure if camera safe and eye safe are correlated, but I would hope/expect that they would not release something that isn't known to be eye safe. I guess it's possible that the long term effects could prove bad, and we will all end up getting "Lidar Eye" dead spots in our vision.

[dylan604]

Digital camera sensors are much more sensitive than eyeballs, so it's not out of the realm of possibility that it won't leave a permanent line across your eyeball like it can to a camera sensor

[slashdave]

Lidar Eye? No, how the heck would that happen? I mean, there is a dangerous source of light outside (we call it the "sun"), and yet we manage fine.

[HighGoldstein]

When it becomes a widespread issue they'll just release Meta Glasses 5/Apple Vision 3 with the appropriate eye protection, and vision will be very affordable.

[loeg]

The existing regulations here might be insufficient. There is definitely risk if the devices are not carefully designed to be safe.

[krackers]

To date I can't think of any existing lasers which you are intended to look at during daily use. Most consumer facing lasers are either class 1 but hidden (CD-ROM), or class 2 but basically not shined into your eye (barcode reader).

There was another discussion a week back https://news.ycombinator.com/item?id=46126780

The lack of accessible certification/testing docs for the lidars is also worrying. Where is the proof that it was even tested? Was it tested just via simulation, via a dummy eye stand-in, or with a real biological substitute?

What if there are biological concerns other than simply peak power involved with shining NIR into the eye? (For instance, it seems deep red light has some (beneficial) biological effects on mitochondria. How do we know that a pulsed NIR laser won't have similar but negative effects, even if it doesn't burn a hole in your retina.)

[slashdave]

In terms of plain wattage, it cannot be dangerous. Unless, of course, you were to stand with your eye up against the sensor and maybe stare at it for a few minutes.

[eutectic]

Lidars use pulsed lasers with peak powers up to the kW range.