https://www.forbes.com/sites/davidhambling/2021/03/11/us-army-develops-laser-machinegun-firing-light-bullets/?
A new U.S. Army laser has more in common with Star Wars blasters than anything currently used by the military, firing a stream of bullet-like pulses of light that hit the target with explosive effects.
The U.S. Navy fielded its 30-kilowatt LaWS laser in 2014, and since then an arsenal of new lasers with 50, 100 and 150 kilowatts of power have been developed on aircraft, ships and ground vehicles. All of them produce a continuous beam that has to be maintained on the target until it melts or burns a hole.
The period waiting for the beam to do damage is known as ‘dwell time’ and is typically a matter of seconds. Obviously it presents a major targeting challenge, one reason why the preferred targets are drones and cruise missiles that do not take evasive action.
The U.S. Army’s Tactical Ultrashort Pulsed Laser for Army Platforms is different, producing a series of short but extremely powerful pulses rather than a continuous beam. To add to the sci-fi flavor, unlike invisible infrared lasers currently in use, the pulses may also be visible. The weapon will fire up to 50 pulses a second.
“Pulse trains [a rapid series of pulses] literally chew through target material,” noted a military presentation on weapon applications.
The rapid expansion of gas produced by ablation can also produce a powerful shockwave. This was previously explored in the Pulsed Energy Projectile, a U.S. Army project involving a chemical laser in the early 2000s which vaporised outer clothing to produce a stunning but non-harmful flash-bang effect. The idea was to create a long-range alternative to rubber bullets but was shelved because of the limitations of the chemical lasers of the time.