Stereopsis

Stereopsis is the visual perception of 3D objects. It is the perception of something having physical extent towards or away from the viewer, being solid and 3D.

The human perception of stereopsis is formed in large part from binocular disparity.

The term "stereopsis" comes from Ancient Greek stereós meaning 'solid', and ópsis meaning 'appearance' or 'sight'.

It is related to depth perception, but depth perception is vague, and may only mean identifying the distance away of a flat object.

Depth perception due to focal cues is a main component.

Head movement plays a part, such that the human brain likes to see a small perspective shift, which helps.

The biggest contributor to stereopsis is binocular disparity. However, monocular stereopsis exists.

VAC causes partial stereopsis.

There is a ratio of neurons dedicated to binocular disparity decoding compared to ciliary muscle focal state reading.