Working Distance
One of the basic parameters for the selection of a lens is the distance between the object that has to be captured and the leading edge of the lens - the so-called "working distance".
Important: Every lens has a minimum object distance (MOD). If the working distance is less than the MOD, it is not possible to focus the lens any more. Fortunately, this problem can be easily solved with extension rings that are put between the lens and the industrial camera.
The article Lenses for industrial cameras describes in detail how to use the parameter "working distance" for the calculation of the focal length.
