By John Timmer
Publication Date: 2026-02-18 19:01:00
To read the data back, there are several options. We’ve already had great success using lasers to read data from optical disks, albeit slowly. But anything that can pick up the small features etched into the glass could conceivably work.
With the above considerations in mind, everything was in place on a theoretical level for Project Silica. The big question is how to put them together into a functional system. Microsoft decided that, just to be cautious, it would answer that question twice.
A real-world system
The difference between these two answers comes down to how an individual unit of data (called a voxel) is written to the glass. One type of voxel they tried was based on birefringence, where refraction of photons depends on their polarization. It’s possible to etch voxels into glass to create birefringence using polarized laser light, producing features smaller than the diffraction limit. In practice, this involved using one laser pulse to create…
