There are several instances of the Observers using this pattern in their technology. It can be seen inside September's binoculars, on a device used to control or signal the hitman Donald Long, on the cap of a man who was chasing after the beacon in The Arrival, and in Donald's apartment in Season 5. It is not clear why this pattern is so important to the Observers, or a least to the science team, but it nevertheless saturates the areas related to them.