As a part of the 7 Techmakers and a Microphone panel tonight at Google I/O, Project Glass Staff Hardware Engineer Jean Wang dropped in this slide reflecting on the process of developing the headset. We've seen pictures of a few early Glass prototypes before, but as she describes, this shows off the full process from strapping a cellphone to a pair of goggles along with a pico projector shining directly into the wearer's eyes. The jump from off the shelf components to custom 3D-printed materials is represented in the third version (top right), and allowed the progress seen along the bottom row.
She also got a laugh pointing out that the Glass-inspired SNL skit starring our friend Fred Armisen wasn't "too far off" the team's initial efforts in gesture and voice control. The panel itself focused on a series of TED-style segments featuring seven women discussing being technical leaders inside their company. You can check out the entire thing embedded after the break or just zoom to the Google Glass part (6:13) for more details.