Introduction - Matrox Iris GT with MIL Manual

80 Appendix C: Selecting a lens

Introduction

This appendix includes information on lens selection, an important consideration
when building your application.
The primary consideration during lens selection is that the focal length of the
selected lens meets your application's requirements.
The focal length is the distance between the principal plane and the point where
parallel light rays, bent at the principal plane, intersect the optical axis.
Parallel light rays
Optical axis
Parallel light rays
❖ Note that each lens is designed for a specific focal length; a zoom lens is designed
for variable focal lengths.
Principal plane (H2)
Focal point
Focal length
Image plane