HoloLens promo video gives a glimpse of early prototypes

During Microsoft's Build 2015 event earlier today it displayed a "Closer look at the hardware" promo video for its HoloLens AR headset. It's the normal fluff and info we're expecting about augmented reality, but as RoadtoVR points out, there are a few brief glimpses at earlier versions of the headset in there too, plus a look at the current unit blown apart so you can see what's inside. They're similar to the Google Glass prototypes we saw during its run up to the Explorer model, and give us an idea of how hard it is to shove all that hardware into something that might fit on a human face. Of course, it doesn't bring us immediately closer to Windows Holographic experiences in real life, but until we get our hands on one just appreciating the headset's history and technology will have to do.