Some background on laser weapons, relevant to Ukraine's Sunray reveal ...

The first functioning (optical) laser was invented the year I was born. Growing up, I kept seeing laser breakthroughs in the news and a lot of almost SF-level successes and predictions. Lasers were sexy, and I paid a fair amount of attention to them, including taking a college-level course in optics. Although often presented in the popular press as real-life 'death rays' or 'disintegrator rays', the earliest successes were due to low-power applications of the highly coherent nature of laser light, making holograms a practical reality, and greatly increasing the potential of interferometry to make exquisitely precise measurements. Real power laser capabilities built up gradually, with developments like CO2 (10,600 nm) and Nd-YAG (1064 nm) IR lasers offering the potential of lasers as cutting tools in factories, and, if scaled up enough, weapons.

Actually, development of anything as complicated as a laser weapon is seldom a straight-line series of logical developments -- many ideas were introduced over the years, some failing, some succeeding, some needing 'tweaking' or even radical new developments to become practical, and some falling into somnolence, to be revived later.

Much of the progress has been kept within classified bounds by various military institutions and their contractors, making a really comprehensive assessment of current progress problematic. I was curious to see if the Ukranians had fielded a gas-dynamic or especially chemical GD laser, some of which do not require electrical power as their primary energy input, but use combustion of liquid or gaseous fuels/explosives -- something not exactly unfamiliar to the battlefield, and which excited considerable interest at one time. That does not appear to be the case for Sunray, but exactly what they have is unclear. My best guess is a (generator-recharged) supercapacitor/battery-powered, flashlamp-pumped fiber optic (Yb-YAG was specifically mentioned in one context) laser based on what little description is available. (I believe Nd-YAG the first to be explored because of the relative abundance of Nd, which is actually used in goggles for glassblowing etc.; the rarer Yb probably makes for a more efficient/effective laser beam by some criteria I'm not familiar with.)

Trying to catch up on all this reminded me of how long it's been since I studied anything about lasers -- I used to scan every issue of Laser Focus magazine for developments re. anything I could understand (it helped that I worked in the library which handled holdings of that journal for the 'Tute). It's a huge and fascinating field, and one I might have gone into under other circumstances; financially it might have been the more practical choice by a good measure, but I've been rather impractical in my career choices. :/

Anyway, here are some links, not the most exhaustive or informative, but if you didn't know anything about laser weapons systems, now you'll know more:

https://universemagazine.com/en/ukraine-unveils-sunray-laser-air-defense-system-prototype-to-counter-drones-what-we-know/
https://universemagazine.com/en/star-wars-is-here-what-laser-weapons-are-and-how-they-could-change-air-defense-systems/

(Caveat: I'm not sure who runs Universmagazine.com exactly, but their store appears to operate through the Ukraine postal system .... )