John Crichton wearing oculars
A view of Tavleks through an ocular
Oculars were lightweight, image enhancement devices that could be worn on the foreheads of humanoids such as Sebaceans. They displayed an enhanced image back to the wearer, and provided tactical information in the image. They were ideal tools for reconnaissance, as they had the capability to provide a close-up, detailed view of the enemy from a great distance and were able to zoom-in without having to be adjusted by the user's hands.
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Oculars are derived from Farscape.