Just in case anyone secretly had the idea that Valve Software’s VR and other hardware somehow sprang fully-formed from a lab, here are some great photos and video of early prototypes, and interviews with the people who made them. Some of the hardware is quite raw-looking, some of it is recognizable, and some are from directions that were explored but went nowhere, but it’s all fascinating.

The accompanying video (embedded below) has some great background and stories about the research process, which began with a mandate to explore the concepts of AR and VR and determine what could be done and what was holding things back.
One good peek into this process is the piece of hardware shown to the left. You look into the lens end like a little telescope. It has a projector that beams an image directly into your eye, and it has camera-based tracking that updates that image extremely quickly.
The result is a device that lets you look through a little window into a completely different world. In the video (2:16) one of the developers says “It really taught us just how important tracking was. No matter [how you moved] it was essentially perfect. It was really the first glimpse we had into what could be achieved if you had very low persistence displays, and very good tracking.” That set the direction for the research that followed.