[N_A_T_E]

I worked in a laser lab for a few months early in my career. After the safety training I fear lasers getting near my eyes in situations most people don't care about. I even look away from barcode scanners at grocery stores. Sometimes I wonder about lidar being shot in all directions from those self-driving cars around SF.

[Miraste]

There's been at least one sketchy self driving startup that drove their LiDAR hard enough they burnt holes in journalists' camera sensors at CES.

https://arstechnica.com/cars/2019/01/man-says-ces-lidars-las...

[neilv]

I'd wondered about the eye safety of LIDAR on prototype autonomous vehicles, but then thought "surely anything at all unsafe to eyes wouldn't be allowed on public streets."

Now I'm reminded of all the unregulated recklessness in some technical topics that I do understand, and realizing it's silly to assume.

[sersi]

Should I be concerned about the lidar in my dreame robot vacuum (L10s ultra) and my 3 years old whose head is closer to the ground than me?

I never thought about it before but you'r comment worries me.

[bleakenthusiasm]

So going by what they aimed for in building the laser: No. The nominal power and wave length of all of these appliances is less harming to the eye than going outside on a sunny day and forgetting your sun glasses.

The issue here I guess are malfunctions or rather cheap products with bad calibration. For total safety you'd have to get someone to measure input and output of the laser.

I'd love to reassure you about something like low input power, but at the end of the day with cheap products you don't know. If a higher powered laser was cheaper at the time of production, the extra milliwatts would probably be negligible compared to overall power consumption of the robot.

So the lidar is unlikely to immediately cause eye damage at a glimpse, but if your kid likes to chase the robot and thus might look into it for longer periods of time, maybe look into options of checking the laser's actual input power.

[Doxin]

Keep in mind that LIDAR is moving lasers too, which are allowed to be higher power but should have an interlock that turns the laser off when it stops moving.

I'll leave the extrapolation on how that could go wrong to you.

[sersi]

Hmm my kid does like to chase the robot.

It seems rather difficult to measure the laser input power though. Apart from trying to reverse engineer the robot?

I guess I'll just make sure that it's not turned on if my kid is awake at home.

[kqr]

Wait, are barcode scanners lasers? I've always thought of them as red lamps because their cone spreads out so widely quickly.

[calfuris]

Some of them are, some of them aren't. There are obviously laser based ones that are easily recognizable as they produce a pattern of lines instead of a relatively evenly lit field. It's surprisingly difficult to find a picture of that, but I found a video that shows it well[1]. The ones that produce even illumination are probably LED based.

[1] https://www.youtube.com/watch?v=PIn00-qW5WI&t=1m34s

[rtkwe]

It's a scanning dot moving fast enough to appear as a cone.

[hinkley]

The stationary ones used to have a spinning mirror with a laser pointed at it. You used to be able to look in the machine and see it. Dunno how they do it now for the handheld scanners. Smaller mirror or some other trick like piezo?

[rtkwe]

Hand scanners for a while have been able to use just LEDs to illuminate the barcode it turns out. Way cheaper than having so many moving parts like the older laser based scanners.