Lasers vs other light sources by Ciro Santilli 34 Updated Created
The key advantages of lasers over other light sources are:
One cool thing about lasers is that they rely on one specific atomic energy level transition to produce light. This is why they are able to to be so monchromatic. Compare this to:
  • incandescent bulbs: wide black-body radiation spectrum
  • LED: has a wider spectrum fundamentally related to an energy distribution, related: Why aren't LEDs monochromatic
  • TODO think a bit about fluorescent lamps. These also rely on atomic energy transitions, but many of them are present at once, which makes the spectrum very noisy. But would individual lines be very narrow?
As such, lasers manage to largely overcome "temperature distribution-like" effects that create wider wave spectrum
Video 1.
Crazy difference between 5W laser and 5W LED by Brainiac75
. Source. Baseic but good. Uses a laser photometer.