Fairchild CAM/CMOS-2K.LS - Manual (Page 31)

4.9 Lens Modeling
Several camera companies have included this and like information in their manuals. For reference
material it is very useful.
The focal point is the point at which the image of an infinitely distant object is brought to focus.
The effective focal length (f’) is the distance from the second principal point to the second focal
point. The back focal length (BFL) is the distance from the image side of the lens surface to the
second focal point. The object distance (OD) is the distance from the first principal point to the
object.
Figure 4.9.1
Fairchild Imaging • CAM/CMOS-2K.LS Line Scan Camera User’s Manual • Rev C• 31 of 42