Using a zoom lens in monocular vision seems to be an interesting idea.
The principal aim of this paper is to prove that it is possible to in
fer 3-D information from a set of images taken with a zoom lens. In th
e first part of the paper, a precise study of the optical properties o
f such a lens gives two major results: The intersection between the op
tical axis and the image plane can be independently and accurately det
ermined, and the pin-hole model cannot be used directly for the approx
imation of such a complex lens system. To explain the optical phenomen
a occurring during a zoom-lens focal-length change, it is shown that a
thick optical model must be considered. Finally, experimental results
of reconstruction, from a set of real images, are given.