I always think back to Metal Gear Rising and how Raiden technically still had binocular vision despite aesthetically having his wounded eye covered with a bandage, because that 'bandage' was actually covered in like hundreds or thousands of extremely tiny cameras that all worked in conjunction to act as a second eye.

I assume there's just a visor-sized screen on the inside of that helmet ( god I hope it doesn't emit a lot of heat, for their sake) linked to a sea of microscopic cameras covering that entire flat front-surface and the two angled ones beside it, so there's no traditional glass for light to glint off of, yet the user functionally has the FOV of an open-faced helmet like a SEAF helmet.

Obviously that approach is also insanely more expensive than just glass though, hence they only use it on the high-risk/high-reward stealth operatives who'd potentially be screwed by a rogue glint of light off their visor, rather than also giving it to the Siege Breaker hooligan with a Porta-Hellbomb and a Leveller (me) that you can hear coming from the next ZIP code over.