Bright Sword starts with the grenade flat.

Chapter 397 Difficulties of High Energy Laser Weapons
The reason for this is actually mainly Liu Xiu's own fault. Because Liu Xiu knew in advance that this world was a wandering blue planet, Hua Xia's scientists and research directions were all focused on interstellar navigation. On the contrary, the investment in the research and development of future weapons such as lasers was greatly reduced.

Therefore, the research and development progress of the laser weapons on the Wandering Blue Star is naturally not as high as that of the laser weapons in the world before Liu Xiu traveled through time.

But the world before Liu Xiu traveled through time was different. Because there was no solar crisis, there was naturally no motivation for interstellar travel. After all, occupying Mars or other planets that are uninhabited and unsuitable for survival is not as practical as defeating other crops and occupying their land!

Therefore, knowing that high-energy laser weapons are the general direction of development of future new weapon systems, and the huge role of laser weapons in anti-missile defense, it is natural that more and more people are focusing their research on laser weapons.

However, although the research on laser weapons was very advanced in the world before Liu Xiu, it was difficult to use them in actual combat. Even if some larger laser systems were demonstrated, they were mainly experimental in nature.

Of course, there are three main factors that restrict this. The first is the interference of atmospheric conditions on laser weapons. The second is the upper limit of laser weapon power. The third is the source of continuous laser high-energy energy.

Let's talk about the atmospheric interference first. Many people intuitively believe that laser weapons cannot be used immediately if there are low clouds, rain, snow, fog or haze, instead of sunny days. In fact, this is a misunderstanding. For low-power lasers, fog and low clouds can seriously interfere with the use of lasers.
However, for large weapon-grade lasers above 100 kilowatts, this is not a big problem, because there are infrared atmospheric windows and adaptive light waves. Unless it is a thunderstorm cloud with a thickness of more than 10 kilometers, ordinary clouds and haze cannot completely block high-energy laser beams. Therefore, for high-energy weapon-grade lasers, atmospheric interference is the easiest factor to overcome.

The second key point is the instantaneous emission power of high-energy laser weapons. The most significant difference between laser as an ordinary light source and a weapon is its instantaneous power. Ordinary laser beams can only dazzle the eyes, but if you want them to be lethal from a few kilometers away, the instantaneous power of such laser beams must be more than ten kilowatts.

Lasers of this power can only ignite flammable materials such as rubber and wood at a distance. If you want to burn through composite materials, aluminum or even steel immediately, the instantaneous power of the laser beam must be above 50,000 watts. 50,000 to 100,000 watts is also the basic threshold for laser hard-kill weapons.

If they can't even cross the threshold of a 100,000-kilowatt laser, then at best they can only attack small civilian drones.

If you want to burn through genuine fighter planes, missiles and warships from a distance of tens to hundreds of kilometers, the power is obviously not enough. Moreover, the lower the instantaneous power of the laser beam, the longer the light spot needs to stay on the same target. For example, a 50,000-watt laser takes four to five seconds to burn out the shell of an incoming rocket, while a 100,000-watt laser beam takes about one second.

For a 200,000-watt laser beam, only millimeter-level is enough. The shorter the time required for the laser to burn through the target, the simpler the aiming and tracking system, and the stronger the multi-target capability.

Therefore, regardless of the sea, land, or air, the best laser for long-range killing is to have a transmission power of 2 watts or more. If it can reach watts or more, it would be the best. If it can reach watts to million watts, it can reach the strategic combat level of intercepting hypersonic missiles.

Of course, high-energy laser weapons are not so easy to make. For example, the 747 laser machine that Mi Tuo had made before Liu Xiu traveled through time used to be a stacked thin-film laser technology, and had to be immersed in liquid to dissipate heat.

Of course, this thing is, to put it bluntly, a chemically excited laser. Ultimately, practice has proven that this type of laser is heavy and polluting, and is not suitable for use as a weapon. In the end, the 747 laser machine was dismantled after hitting a suspicious real target. This shows that this approach is a dead end.

After nearly twenty years of development, it was basically confirmed that fiber laser phased array technology and slab lasers are the reliable ways to produce laser weapons with higher powers of 200,000 watts and above.

For example, fiber lasers can be made relatively light, so they can be installed on tactical aircraft to burn through incoming missiles or directly use them as machine guns to shoot enemy aircraft several kilometers away. Fiber lasers mostly use glass optical fibers doped with rare earth elements as gain media, which can be developed on the basis of fiber amplifiers: high power density is easily formed in the optical fiber under the action of pump light. However, the maximum instantaneous power of fiber lasers is difficult to exceed 300,000 watts.

Of course, this is powerful enough to kill targets within a dozen kilometers at an altitude of more than 10,000 meters. Since it is relatively light, it can be installed on a ground vehicle and is sufficient to kill targets within five kilometers.

The strategic lasers fixed on the ground that can hit satellites and long-range missiles, as well as the strong lasers that can be installed on warships and hit anti-ship missiles, ballistic missiles and aircraft hundreds of kilometers away, mostly use slat lasers.

The slab laser is the first high-energy laser that can reach the megawatt level, or trillion watt level, and is a type of high-power laser.

The laser working material is in the shape of a strip, while the geometric shape of the working material of an ordinary solid laser is a round rod. The direction of the temperature gradient is perpendicular to the direction of light propagation. When operating under heat load conditions, severe thermal lens effects and thermo-optical distortion effects will occur, reducing the beam quality and limiting the further increase of laser power.

In slab lasers, the temperature gradient occurs in the thickness direction of the slab. The light propagation direction is approximately parallel to the temperature gradient direction, which can basically avoid thermal lens effect and thermo-optical distortion effect, and greatly improve the laser output power.

A one-megawatt-level laser is powerful enough to instantly burn through most thick metals at a long distance; in a clear night sky over the plateau, it can already kill satellites orbiting below an altitude of 2,000 kilometers.

It has the preliminary performance of a strategic laser weapon. Of course, the slat solid laser is large in size and weight, and can only be deployed on large warships and fixed bases on the ground.

It's just that in the world before Liu Xiu traveled through time, although everyone understood the main idea of ​​slat laser.

However, we encountered the third major hurdle, which is how to continuously provide high-power electricity.

If it is powered by a normal power grid, not only will the equipment be huge and overweight, but it will also be insufficient to emit high-power pulses in the single digits. This is also the main reason why none of the sea-based and land-based combat lasers in the super-powered world before Liu Xiu traveled through time could reach the 300,000-watt level.

However, for Liu Xiu, the Wandering Blue Star has already been able to overcome the problems of continuous power supply and instantaneous high-power power supply.

After all, with heavy nuclear fusion, hydrogen fusion, and even a supercapacitor for superconducting energy storage, Liu Xiu doesn't have to worry about the functionality of the super laser weapon at all.

(End of this chapter)