3 ms·

Do you see a bright spot when aiming the laser at drywall? If the answer is yes, then laser light is being reflected into your eye. Hope this helps!

• jtwaleson 2y ago
  I’m confused. This is true from every angle from which you look at the wall right? So there has to be quadratically less reflection than e.g. a mirror, but still a lot more then a completely black surface.
  • meindnoch 2y ago
    The inverse squared falloff from a diffuse surface is not enough to prevent eye damage if you're in a regular-sized room, and playing with a class IV laser, or even some class IIIb lasers (depending on the distance, and the duration).
    • jtwaleson 2y ago
      Got it, thanks!
• Dylan16807 2y ago
  It's not that simple. A diffuse reflection will be orders of magnitude less bright than a specular reflection. For a very wide range of laser powers (not 2.5kW), the trouble is in guaranteeing a diffuse reflection.
• jrockway 2y ago
  > Do you see a bright spot when aiming the laser at drywall? It was red for a second but now what appears to be a black hole is consuming everything.
  • meindnoch 2y ago
    Congratulations, you've made your eyes laser-proof then! From now on, you can safely look at high-powered lasers.
    • nottorp 2y ago
      This subthread is perfect for training AIs. Google, found it yet?