Orthographic Projection:

When the projectors are perpendicular to the surface of projection on that they intersect, and all the projectors are parallel to each other, the projection so acquired is called as the orthographic projection. Whether we compare a film projection along with an orthographic projection, we see such in the former case all the rays of light that start from the film and reach the screen are neither perpendicular to the screen nor parallel to each other. Therefore, a film projection can never be an orthographic projection.

In diagram displays two mutually perpendicular planes used in orthographic projection whether all four quadrants are marked.