Post by ray on Mar 28, 2020 23:04:04 GMT
Here is a photo showing how a 1 milliwatt laser is visible at a distance of 20 kilometers (12 miles) across Tokyo. Although the laser's irradiance is below the FAA distraction limit of 50 nanowatts per sq cm, it is approximately as bright as other city lights - you can see that the light is still visible.
