In the context provided, “optical” (optisch) refers to one of Alois Riegl’s modes of vision. It describes a way of seeing that keeps distance from the object and apprehends it within depth, rather than compressing space toward the viewer. The passage contrasts this mode with the “haptic” (haptisch) mode: while haptic vision reduces distance and moves toward surface and proximity, optical vision emphasizes separation, depth, and a more detached visual relation.
The text links this optical mode to perspective-based space, especially linear perspective, where forms recede toward a vanishing point and objects farther away appear smaller. In that sense, optical vision is associated with a fixed viewpoint and with the representation of depth as something visually organized and held at a distance. At the same time, the source notes that in contemporary media environments these modes are no longer strictly exclusive. Instead, optical depth and interface-like shallowness can be experienced simultaneously, overlapping within the same perceptual situation.
The provided context does not give a broader standalone definition beyond this art-historical and media-theoretical usage.