Daily Magazine

n 1880 Alexander Graham Bell Invented the Photophone. While his earlier invention, the telephone, uses electricity to transmit voice communications, the photophone relied on a beam of light to send sound. A person's voice was projected through an instrument toward a mirror. The vibrations of the voice caused vibrations in the mirror. Sunlight was then directed into the mirror, where the vibrations were captured and projected back to the photophone's receiver where they were converted back into sound.

Bell believed that the photophone was "the greatest invention [I have] ever made, greater than the telephone". He might be right, the photophone was a precursor to the fiber-optic communication systems. The reason why the photophone didn't take off during Bell's time is simply that the system was useless whenever the weather was cloudy.

It’s the end of October, when the days have already grown short in Redmond, Washington, and gray sheets of rain are just beginning to let up. In several months, Microsoft will unveil its most ambitious undertaking in years, a head-mounted holographic computer called Project HoloLens. But at this point, even most people at Microsoft have never heard of it. I walk through the large atrium of Microsoft’s Studio C to meet its chief inventor, Alex Kipman.

The headset is still a prototype being developed under the codename Project Baraboo, or sometimes just “B.” Kipman, with shoulder-length hair and severely cropped bangs, is a nervous inventor, shifting from one red Converse All-Star to the other. Nervous, because he’s been working on this pair of holographic goggles for five years. No, even longer. Seven years, if you go back to the idea he first pitched to Microsoft, which became Kinect. ...