Laser Weapons – The Military’s New High-Tech Toy

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Nations around the world are rapidly developing high-energy laser weapons for military missions on land and sea, and in the air and space. Visions of swarms of small, inexpensive drones filling the skies or skimming across the waves are motivating militaries to develop and deploy laser weapons as an alternative to costly and potentially overwhelmed missile-based defenses.

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The high-energy laser systems that are finding military applications are based on solid-state lasers that use special crystals to convert the input electrical energy into photons.

When a laser beam interacts with a surface, it generates different effects based on its photon wavelength, the power in the beam and the material of the surface – low-power lasers are harmless to surfaces and used for lightshows or as pointers, higher-power laser systems can be used to cut through biological tissue in medical procedures, and the highest-power lasers can heat, vaporize, melt and burn through many different materials and are used in industrial processes for welding and cutting.

Recent years have seen an increased military use of high-energy lasers, whose main advantage is that they provide an “infinite magazine.” While traditional weapons have a finite amount of ammunition, a high-energy laser can keep firing as long as it has electrical power.

However, the great innovation of laser weapons faces the challenge of distances – while an industrial laser is just a few inches from its target, military use involves much larger distances. Being able to burn through materials at safe distances requires tens to hundreds of kilowatts of power in the laser beam.

Furthermore, high-energy lasers are currently only 50% efficient and therefore generate a tremendous amount of waste heat that has to be managed. This means such lasers require extensive power generation and cooling infrastructure that limits their types of effects and applications in different weapons.

The infrastructure’s size affects the weapon’s function- the smallest weapons carried by trucks and fighter jets have the least space and are therefore limited to low power tasks like downing drones or disabling missiles. Bigger lasers can be carried by ships and larger aircraft and burn holes in boats and ground vehicles, and permanent ground-based systems have the least constraints and the highest power.

Another issue of platform-based high-energy laser weapons is that they do not actually have infinite magazine power, since they are dependent on their power source that has to fit on the platform carrying the laser, limiting capacity.

High-energy laser weapons will likely continue to evolve with increased power levels that will expand the range of targets they can be used against.