It would be class 3r, for which direct retina exposure is "low risk". In general for pulsed lasers you can use the duty cycle. I did more analysis in another

It would be class 3r, for which direct retina exposure is "low risk". In general for pulsed lasers you can use the duty cycle. I did more analysis in another comment: Using a maximum permissible exposure chart gives a better sense of danger. Lidar pulses are on the order of 10 nanoseconds, or 1/100th the smallest division on this chart[2]. Even so, you can see that the maximum safe power for 1550 nm is somewhere between 8 and 10,000 watts, at least 800x more than the lidar emits. 1550 nm doesn't chemically damage biological receptors. The damage would have to be thermal, but the laser is pulsed for an incredibly short time and even if it wasn't it's well under what you can be exposed to indefinitely. [2] https://en.wikipedia.org/wiki/File:IEC60825_MPE_W_s.png https://en.wikipedia.org/wiki/File:IEC60825_MPE_W_s.png