51�Թ�

The 3D-printed sculpture pictured above shows how a stereographic projection translates from a sphere to a plane—the curves on the sphere become straight lines on the plane.

The 3D-printed sculpture pictured above shows how a stereographic projection translates from a sphere to a plane — the curves on the sphere become straight lines on the plane.

The kind of projection most extensively used is the “stereographic projection.”

The stereographic projection, however, represents the poles and zone-circles on a plane surface and not on a spherical surface.

A stereographic projection of a rhombohedral crystal is given in fig.