Topics: Lasers, Optics, Plasma, Research, Star Trek, Star Wars
In science fiction, firing powerful lasers looks easy — the Death Star can just send destructive power hurtling through space as a tight beam. But in reality, once a powerful laser has been fired, care must be taken to ensure it doesn’t get spread too thin.
If you’ve ever pointed a flashlight at a wall, you’ve observed an example of the diffusion of light. The farther you are from the wall, the more the beam spreads, resulting in a larger and dimmer spot of light. Lasers generally expand much more slowly than the beams from flashlights, but the effect of diffusion is important when the laser travels a long way or must maintain a high intensity.
Whether your goal is to achieve galactic domination or, more realistically, to accelerate electrons to incredible speeds for physics research, you’ll want as tight and powerful a beam as possible to maximize the intensity.
In their experiments, researchers can use devices called waveguides, like the optical fibers that might be carrying the internet throughout your neighborhood, to transport lasers while keeping them contained to narrow beams.
Plasma guides maintain focus of lasers, National Science Foundation Public Affairs