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by _ph_ 2419 days ago
It is almost impossible to create a coating that can reflect high-power laser pulses. Even if the coating reflects 99.9% of the light, it absorbs 0.1% of the light. When we are talking about laser pulses strong enough to melt steel projectiles, the absorbed light will quickly destroy the coating and then the projectile is vulnerable again. Also, the coating has to survive the launch/firing of the projectile without getting hazed.

I was using pulse lasers in the lab and traditional silver mirrors would get damaged by pulse energies over 100mJ. They would just turn black. The solution was to use interference mirrors for the exact wavelengths of the beam to reflect, which wouldn't have any absorption and such could survive large pulse energies. But those mirrors are limited to the exact wavelength at precise angles.
1 comments
holoduke 2419 days ago
You need to find out the wavelength of the laser. Once you know the wavelength you can design a reflective shell around the projectile. Certain ceramics with proper coating are really good in scattering energy and are extremely resistant to heat.
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CharlesColeman 2419 days ago
> You need to find out the wavelength of the laser. Once you know the wavelength you can design a reflective shell around the projectile. Certain ceramics with proper coating are really good in scattering energy and are extremely resistant to heat.

That sounds impractical. Either you're trying to coat shells on demand in wartime, or stocking extra quantities targeted to this or that wavelength. If you're already stocking extra ammunition, it sounds better to just overwhelm the defensive system with more shells, like another commenter suggested.

If you're going to design something new, maybe something more like a MIRV launcher that fires three shells in the time it currently takes to fire one.

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mcguire 2419 days ago
It's likely that your opponent is fielding only a limited number of laser projectile countermeasure systems, and also likely that they are related and only using a limited number of wavelengths.

But yeah, just throw a bunch of things and swamp their targeting systems.

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