Introduction

At Lockheed Martin, it used to take a technician two painstaking days to measure 309 locations for certain fasteners on a particular curved panel. The same job now takes a little more than two hours with the Microsoft HoloLens. It looks like a bulky set of safety goggles and it layers digital information over the real world. Before ibn Al-Hatham, optical devices had been cumbersome. But gradual spread of knowledge inspired new ideas.