Specifying 3D position with 2 coordinates on a Screen

Many experiments in Vision Science have been performed with human or non-human subjects watching visual stimuly displayed on a flat 2D screen (often a monitor screen). In general, this screen is perpendicular to the subject's line of sight and is thus often called tangent screen (this is not exactly the case in this figure as the cat's head is not in front of the monitor).

(Image from cloudzilla, CC BY 2.0, via Wikimedia Commons).

The simplest ways to simulate a tangent screen in a 3D environment are presented in the following sub-sections:

• Definition of a Tangent screen
• Tangent screen with 2D Cartesian coordinates
• Tangent Screen with 2D Perimetric coordinates