The compact imaging assembly has an electronic imager and an objective
lens with a focal length fo. The objective lens receives light and forms
an image of the object on the imager's image plane. The image plane has a
maximum effective dimension DI. The objective lens has a first lens group
comprising two to three elements with an object surface facing the object
and an image surface facing an image plane. The objective lens also has a
middle lens element with a concave object surface that is facing the lens
group image surface, and a final lens element that has a positive power.
The distance from the lens group object surface to the image plane is TT.
The lens group, the middle lens and the final lens elements are coaxially
aligned and on an optical axis normal to the image plane.