Laser weapon

• The Chinese People's Liberation Army has invested in the development of specialized coatings
• Laser beams begin to cause plasma breakdown in the atmosphere at energy densities of around one megajoule per cubic centimetre.
• The system operates by directing an intense beam of energy toward its target

Laser weapons, also known as directed energy weapons, use focused beams of electromagnetic radiation, usually lasers, to damage or disable targets. Such weapons would hold significant advantages over traditional military hardware, including low cost per shot, a limitless magazine, and the ability to engage targets at the speed of light, but whether they will be deployed as practical, high-performance military weapons remains to be seen. 

One of the major issues with laser weapons is atmospheric thermal blooming, which is still largely unsolved. This is exacerbated when there is fog, smoke, dust, rain, snow, smog, foam, or purposely dispersed obscurant chemicals present. A laser generates a beam of light that requires clear air or a vacuum to operate.

Several lasers have been identified as having the potential to be used as incapacitating non-lethal weapons. They can cause temporary or permanent vision loss when directed at the eyes. The extent, nature, and duration of visual impairment resulting from exposure to laser light depend on various factors, such as the laser's power, wavelength(s), collimation of the beam, orientation of the beam, and duration of exposure. Even lasers with a power output of less than one watt can cause immediate and permanent vision loss under certain conditions, making them potentially non-lethal but incapacitating weapons. 

H4 – ruggedized and portable

Although rugged and easily portable, Raytheon’s latest high-energy laser weapon system A laser beam director (LBD) is a critical component in high-energy laser (HEL) weapon systems, it is the beam director, responsible for directing and focusing the laser beam onto a target with precision, that makes the system so powerful. It's a sophisticated optical system that aligns and stabilizes the laser beam, compensating for factors like atmospheric turbulence, platform movement, and system vibrations. 

According to James Gray, chief executive and managing director of Raytheon UK, the company’s High-Energy Laser Weapon System (HELWS) has been used in operations globally, and the British Army is now experimenting with this game-changing capability. 

The experiment marks the first time the British Army has tested a high-energy laser weapon mounted on an armoured vehicle, while also having soldiers trained on the weapon's targeting and tracking technologies.

The system operates by directing an intense beam of energy toward its target, using advanced sensors, and tracking systems to maintain lock-on and accuracy in real time. It has proved effective in real-world conditions, validating its potential as a game-changing technology in modern warfare.

The H4 is designed for counter-drone missions, as well as intelligence, surveillance, and reconnaissance missions, and HELs at this power level (10 kW) tend to be targeted at countering Class 1 or Class 2 drones. The laser is powered by technology from F-1 race car batteries because they can store a lot of power and charge constantly without melting down. Raytheon has enhanced the battery so that has all the energy storage and the ability to recharge while operating.

Although fully sealed the H4 does require light maintenance as the air filters need to be cleaned every few months While fully sealed now, the system does still require some light maintenance. Air filters need to be cleaned every few months and splatter on the main aperture will need to be cleaned.

U.S. laser weapon ready for battle!

The United States has developed it’s LOCUST laser weapon system as an answer to the danger posed by weaponised drones. An arrangement of a tracking system, a power system, and a laser output system work together to detect, track, identify, and engage threats with powerful laser beams. LOCUST uses high-resolution cameras and sensors that provide both a wide field of view for acquisition and narrow, high-precision views for tracking. Tracking various threats in busy or clear skies is done by means of an advanced gimbaled electro-optical tracking system unit that features a tracking system, a powerful telescope, a laser rangefinder, an acquisition tracking system, and a targeting laser. 

Another laser weapon under development by the United States, The Valkyrie, is a 300-kilowatt laser weapon system developed under the US Army's Indirect Fire Protection Capability-High Energy Laser (IFPC-HEL) program. It's a prototype designed to complement other defence systems, offering protection against threats like drones, rockets, artillery, mortars, and aircraft. Apparently not intended for direct combat deployment, Valkyrie represents a significant advancement in laser weapon technology for the US military.

Problems

Laser beams begin to cause plasma breakdown in the atmosphere at energy densities of around one megajoule per cubic centimetre. This effect, called "blooming," causes the laser to defocus and disperse energy into the surrounding air. Blooming can be more severe if there is fog, smoke, dust, rain, snow, smog, or foam in the air.

Techniques that may reduce these effects include:

* Spreading the beam across a large, curved mirror that focuses the power on the target, to keep energy density en route too low for blooming to happen. This requires a large, very precise, fragile mirror, mounted like a searchlight, requiring bulky machinery to slew the mirror to aim the laser.

  * Using a phased array. For typical laser wavelengths, this method would require billions of micrometre-size antennae. There is currently no known way to implement these, though carbon nanotubes have been proposed. Phased arrays could theoretically also perform phase-conjugate amplification. Phased arrays do not require mirrors or lenses and can be made flat and thus do not require a turret-like system (as in "spread beam") to be aimed, though range will suffer if the target is at extreme angles to the surface of the phased array.

Countermeasures

A laser generates a beam of light which will be delayed or stopped by any opaque medium and perturbed by any translucent or less than perfectly transparent medium just like any other type of light. A simple, dense smoke screen can and will often block a laser beam. Infrared or multi-spectrum smoke grenades or generators will also disturb or block infrared laser beams. Any opaque case, cowling, bodywork, fuselage, hull, wall, shield, or armour will absorb at least the "first impact" of a laser weapon, so the beam must be sustained to achieve penetration.

The Chinese People's Liberation Army has invested in the development of specialized coatings that can deflect beams fired by U.S. military lasers. Laser light can be deflected, reflected, or absorbed by manipulating physical and chemical properties of materials. Artificial coatings can counter certain specific types of lasers, but a different type of laser may match the coating's absorption spectrum enough to transfer damaging amounts of energy. The coatings are made of several different substances, including low-cost metals, rare earths, carbon fibre, silver, and diamonds that have been processed to fine sheens and tailored against specific laser weapons. China is developing anti-laser defences because protection against them is considered far cheaper than creating competing laser weapons.

Dielectric mirrors, inexpensive ablative coatings, thermal transport delay, and obscurants are also being studied as countermeasures. In not a few operational situations, even simple, passive countermeasures like rapid rotation (which spreads the heat and does not allow a fixed targeting point except in strictly frontal engagements), higher acceleration (which increases the distance and changes the angle quickly), or agile manoeuvring during the terminal attack phase  (hampering the ability to target a vulnerable point, forces a constant re-aiming or tracking with close to zero lag, and allows for some cooling) can defeat or help to defeat non-highly pulsed, high-energy laser weapons.