Doing your own coatings, and HD platter mirrors?

Hey guys, just, thinking.

Hard disk platters are near 100% perfect mirrors, correct?

Would it be feasible to make a sort of laser using a pair of them with coatings on them, sort of like how a HeNe tube works?

I know it sounds sort of silly but I'm just curious.

You wouldn't need coatings on both, just on the OC. And truth be told you could probably get away with a dichro for the OC.

If your intent is a DIY hene it certainly can be done, but the gas mix and proper pressure is crucial. If you wanted cheap mirrors for a double brewster tube, this too is doable. Though, if you've got a double brewster hene tube... you probably have cash for real mirrors and mounts.

HeHg is a great DIYable laser, and I'd love to have one (or even see one!) and you can use a HD platter for the HR mirror. Idr the lasing wavelengths though so I'm not sure if there is a dichro appropriate from common sources.