Hypercentric lens

This is in stark contrast to the behavior of the human eye or any ordinary camera (both entocentric lenses), where further-away objects always appear smaller.

The geometry of a hypercentric lens can be visualized by imagining a point source of light at the center of the entrance pupil sending rays in all directions.

The closer an object gets to that point (the center of the entrance pupil), the larger its image will be.

This inversion of normal perspectivity can be useful for machine vision.

Imagine a six-sided die sitting on a conveyor belt being imaged by a hypercentric lens system directly above, whose entrance pupil is below the conveyor belt.