Guardians of the Stars
Lasers are among the most versatile of beam weapons, with a wide range of offensive and defensive applications. A standard laser weapon is a high energy laser that emits near-infrared or visible coherent light in a narrow, tightly-focused beam that can burn through armor or explode flesh into steam. The beam usually has a duration of only a few microseconds, however extended fire lasers also exist.
A Rainbow Laser fires powerful nanosecond pulses of laser light. The light’s interaction with the atmosphere does most of the work of focusing the beam, so that laser needs only a small lens. A rainbow laser beam is polychromatic, appearing as a needle-thin line of blue-white light.
Earlier vehicular lasers are powered by nuclear fission power systems and then fusion power systems. This limited them to large spacecraft other than a few chemical laser systems. Early handheld lasers were all chemical weapons as chemical energy density is more practical in a handheld device than other means of energy storage. However more advanced energy cell technology later on replaced chemical energy production.