system
Given the following post, respond as if you're commenting on Reddit:
human
Why is it whenever you see powerful lasers used in labs or other areas they are almost allways green? Is this due to how they are produced or is green light a better wavelength for sensors to pick up?
gpt
A Nd:YAG laser is often used as as it can make \~10 nanosecond pulses at low frequency. (so it compresses all your power into a few short burst of very high power). Example: A 4W laser pulsed at 10Hz with a 10 ns pulse gives a 40 MW intensity during the pulse. Incidentally, this is why pulsed laser are so dangerous compared to continuous lasers.   


A Nd:YAG produces 1064 nm light (near IR). High power 1064 nm is very dangerous to work with as you cant see the beam, or reflections etc easily. So, if the wavelength isn't particularly important to the application, most applications will convert to the second harmonic of 1064nm.  The second harmonic of 1064 (nonlinear optics) is 532 nm light (green!) Thus you often get green lasers for very high intensity applications.