Slide 12 of the latest POET presentation is titled “POET’s Datacoms deployment has matured many building blocks relevant to Chip Scale Spectrometers”

On that slide we find details associated with the vertical mirror which POET was working on at the time that Vivek joined the company. It’s purpose is identified as  “Low Loss out of plane coupling and efficient light detection” . We were never advised why they were building this out of plane access but were told that some customers wanted out of plane access to the optical interposer. The detail shows a very small diameter aperture associated with the vertical mirror which projects 21 microns into the optical interposer.  A  human hair is 9 microns in diameter

PowerPoint Presentation (poet-technologies.com)

Size matters