Hey I might recommend you to go to the AR threads, even when EgoAnt mention two, there are a lot of non direct competitors to HoloLens, I posted a lot fo devices, like
Moverio from Epson, the
Atheer AiR Glasses,
Laforge Shima,
Vuzix and the
CastAR.
Some of those threads might need some update, but it's because that tech is evolving pretty fast.
AR is a pretty wide technology, because it's basically anything you can ADD to reality which is not there, that's why Pokemon GO is AR, you can see (through the screen of your phone) some Pokemons added to the real world.