You must have read the Crimson Rites and had the Eldritch Revelation in order to preform the Apertis Oculis.
'Opening The Eye' is a ritual to go to the outer lands. To do it, simply place 4 Eldritch Eyes in the centre keystone inside an Eldritch Altar and then infuse 100 of each primal vis from a wand into the altar. To infuse the primal vis into the node you must use a wand (or scepter, staff) holding sufficient vis on the keystone beneath the node. Once this is done, the node will transform into a rift allowing access to the outer lands. The rift itself takes the shape of a black hole surrounded by a purple vortex.
This research unlocks the infusion recipe for Eldritch eyes.