How does Fra Angelico use linear perspective in The Annunciation at Cortona?

In The Annunciation at Cortona, Fra Angelico employs linear perspective primarily through the architectural structure of the portico. As the colonnade recedes toward the upper left corner of the composition, it creates a sense of depth that draws the viewer’s eye into the space.1

Within this receding architectural setting, the artist utilizes the perspective to integrate a narrative element: a miniature depiction of the expulsion of Adam and Eve from the Garden of Eden. While the central figures of the Archangel Gabriel and the Virgin Mary are intentionally scaled larger than the architecture to heighten the dramatic impact of the holy visitation, the use of linear perspective in the background provides a sophisticated, naturalistic framework that was characteristic of the Renaissance style.12