With a normal (entocentric) lens, magnification differs when changing the distance from the lens, like seeing with our eyes. Additionally, features which are located at the edge of an image are viewed at a different angle than objects in the centre of the field of view (FoV). This makes the measurement task very difficult. Telecentric lenses are used for performing exact measurements of objects because they offer images which represent the exact size of an object regardless of its position within the FoV or its distance from the lens. Like all our products, we offer custom made lenses tailored to your specific needs on request.
Picture of same object': left with a entocentric and added the right with a telecentric lens. One sees clearly left the perspective distortions that come about through the divergent (divergent) beam paths of the entocentric (normal) lens.
