The complex Exponential Function is the complex function that we can define as a power series and that extends the real Exponential function to complex values
This series converges everywhere in the complex plane.
In this page we try to show the geometric nature of the mapping
The Exponential Function verifies
The Exponential Function es periodic with period .
The entiry w-plane (with the exception of the origin) will be filled by the image of any horizontal strip in the z-plante of height .
A line is mapped to a spiral (or to a line or to a circle).
can be interpreted as saying that the Exponential Function "wraps the imaginary axis round and round the unit circle like a piece of string" (Tristan Needham).
The half-plane to the left of the imaginary axis is mapped to the interior of the unit circle, and the half-plane to the right of the imaginary axis is mapped to the exterior of the unit circle (Tristan Needham).
The images of the small squares closely resemble squares and (related to this) any two intersecting lines map to curves that intersect at the same angle as the lines themselves (Tristan Needham).
Tristan Needham - Visual Complex Analysis. (pags. 64-77) - Oxford University Press